Iowa Turfgrass Research Report
|i

I owa S tate U niversity
j University Extension
Ames, Iowa

FG-468/July 2004

Si.M ■1•

Department of Horticulture
Department of Plant Pathology
Department of Entomology
Cooperative Extension
IOWA STATE UNIVERSITY
In Cooperation with the
Iowa Turfgrass Institute

Iowa Turfgrass Field Day Program - July 22, 2004
6 :0 0 a m

E q u ip m e n t D is p la y S e tu p

7 :3 0 a m

R e g is tr a tio n a n d In d u s tr y E x h ib its ( c o f f e e a n d d o n u ts )

8 :3 0 a m

I n tr o d u c tio n - R e g is tr a tio n T e n t

9 :0 0 a m

T o u rs
L aw n C a re G ro u n d s T o u r

T im e
9 :0 0

M: C ra b g ra s s h e rb ic id e
trial - Lukas D ant, Dr.
N ic k C h ris tia n s

9 :1 5
9 :3 0

IG C S A
D e m o n s tra tio n

L: I PM p ro g ra m - Dr.
M ark S h o u r

9 :4 5

1 0 :00

1 0 :15

IPLCA
Demonstration

10 :3 0

1 0:45

1 1:00

J: N a tu ra l o rg a n ic
fe rtiliz e rs - C hris B lu m e

1 1:15

K: A lte rn a tiv e w e e d
c o n tro l p ro d u c ts - R yan
Holl

11:30

1 1:45
1 2:00

D: C ool se a s o n grass
v a rie tie s KB, PR, T F Dr. N ick C h ris tia n s

S p o rts T u r f T o u r

G o lf C o u rs e T o u r

Landscape Tour

P e s tic id e C o u rs e s

M: C ra b g ra ss h e rb ic id e
trial - Lukas D ant, Dr. N ick
C h ristia n s
O rn a m e n ta l G ra s s e s
L: IPM p ro g ra m Dr. M a rk S h o u r

L: IPM p ro g ra m - Dr. M ark
Shour

A: R o u n d -u p rea d y b e n t
p u ttin g g reen c o n v e rs io n L u ka s D ant
B: B e n tg ra s s c o n tro l in
K e n tu c k y b lu e g ra s s tu rf M a rc u s J o n e s

O: P e s tic id e L a w s &
fie ld s tra te g ie s
R e g u la tio n s C h u c k E cke rm a n n
fo r b e tte r tra ffic to le ra n c e S h a d e T re e S e le c tio n
s e e d in g rate s a n d d a te s Dr. D ave M in n e r

C: F airw a y a n d p u tting
g re e n b e n tg ra s s v a rie tie s
- Dr. N ick C h ris tia n s

I: S p e cie s c o m p o s itio n
fo llo w in g s e e d in g a n d
traffic - F e d e rico V a lv e rd e

H: A th le tic

E: R e m ote S e n s in g K: A lte rn a tive w e e d co n tro l
J a s o n K ruse
p ro d u c ts - R yan H oll
F: M ow in g q u a lity and turf
p e rfo rm a n c e M a rk H o w ie s o n
G: B re e d in g - R o u n d -u p
re a d y bent, W in te r to le ra n t
LSTMA
p. rye, g e n e tic d iv e rs ity Demonstration
S h a n R a ja se ka r,
Y a n w e n X io n g

N: Inse ct M a n a g e m e n t Dr. D o n a ld L e w is

H o m e D e m o n s tra tio n
P. P ond M a n a g e m e n t G a rd e n
Dr. Jo e M o rris

P la n t D e te c tiv e s
P ro b le m S o lvin g

M: C ra b g ra s s h e rb icid e
tria l - L ukas D ant, Dr. N ick
C h ris tia n s

Lu n ch
T u rfg ra s s ID and W e e d , D is e a s e , and In s e ct T o u r N o te : M ust a tte n d th is s e s s io n a lo n g w ith s ta tio n s L, N a n d O to re c e iv e
30T, 6 & 10 re c e rtific a tio n . F o r c a te g o ry 5, als o a tte n d ses sio n P w ith Dr. M o rris .

1:00

12:00 pm
12:45 pm

T im e

1 :00 pm

Lunch Served in Exhibit Area
Mower Safety Demonstration
T u rf ID T o u r

E x h ib it A rea

T u rfg ra s s Id e n tific a tio n and W e e d , D ise a se and
Insect C o n tro l T o u r Dr. D ave M in n e r and
Dr. N ick C h ris tia n s
R e q u ire d fo r C a te g o ry 3 0 T , 5,6 & 10
re c e rtific a tio n

il

D e m o n s tra te p ro d u c ts a n d e q u ip m e n t in th e E x h ib ito r A re a .

A
B
C
D
E
F
G
H

1
J
K
L
M

Luke Da nt
Marcus Jones
Dr. Nick Christians
Dr. Nick Christians
Jason Kruse
Mark Howieson
Shan Rajasekar
Van wen Xiong
Dr. David Minner
Federico Val verde
Chris Blume
Ryan Ho 11
Dr. Mark Shour
Luke Dant

Round-up ready bent putting green conversion
Bentgrass control in Kentucky bluegrass turf
Fairway and putting green bentgrass varieties
Cool season grass varieties KB, PR, TF
Remote Sensing
Mowing quality and turf performance
Breeding - Round-up ready bent. Winter tolerant p.
rye, genetic diversity
Athletic field strategies for better traffic tolerance seeding rates and dates
Species composition following seeding and traffic
Natural organic fertilizers
Alternative weed control products
1PM program
Crabgrass herbicide trial

PESTICIDE CERTIFICATION TOPICS
L
N
O
P

Dr. Mark Shour
Dr. Donald Lewis
Chuck Eckermann
Dr. Joe Morris

1PM program
Insect Management
Pesticide Laws & Regulations
Pond Management

Introduction
Nick E. Christians , David D. Minner, and Sind-zhang Fei
The following research report is the 25th yearly publication of the results of turfgrass research projects performed at
Iowa State University. This is the seventh year that the entire report is available on the Internet. This report and the
previous years' reports can be accessed at:
h11p ://1urf gras s.hor t.ia sta te.ed u/
In 2003-2004, a new Roundup Ready® ETQ (Enhanced Turf Quality) Kentucky bluegrass study was initiated. The
trials on fairway and green conversion with Roundup Ready® creeping bentgrass are in their second year.
Morphological and genetic characterization of a number of alternative turfgrass species, including Poa trivialis.
colonial and velvet bentgrass is in progress. The field study of winter hardiness of perennial ryegrass is in its second
year. An important gene potentially responsible for freezing tolerance has been isolated from perennial ryegrass and
further studies on its function are underway.
New fairway height creeping bentgrass, green height creeping bentgrass, and fine fescue studies were established in
the fall of 2003. These plots will be on the field day program on July 22, 2004. New display areas for the Iowa
Golf Course Superintendents Association, the Iowa Sports Turf Manager's Association, and the Iowa Professional
Lawn Care Association were also completed lor use at this field day this year.
We would like to acknowledge Will Emley, superintendent of the ISU Horticulture Research Station: Rodney St.
John, manager of the turf research area; Federico Valverde, research associate; Chris Blume, undergraduate research
associate; Dr. Young Joo, visiting scientist; Luke Dant, Mark Howieson, Marcus Jones, Yanwen Xiong, S.K. Lee,
and Jason Kruse, graduate students; and all others employed at the field research area in the past year for their
efforts in building the turf program.
Special thanks to Mark Hoffman and Sherry St. John for helping to prepare this publication.
Edited by Nick Christians, David Minner and Shui-Zhang Fei, Iowa State University, Department of Horticulture,
Ames, 1A 50011-1100.

Dr. Nick Christians
Phone: 515/294-0036
Fax: 515/294-0730
E-mail : nchris @iastate.edu

Dr. David Minner
Phone: 515/294-5726
Fax: 515/294-0730
E-mail: dminner@iastate.edu

Dr. Shui-Zhang Fei
Phone: 515/294-5119
Fax: 515/294-0730
E-mail: sfei@iastate.edu

IV

«

2004 Iowa State Turfgrass Research Report
Introduction...................................................................................................................................................................................................................iv
Envi ronmcntal Data
2003 Weather Data for the Turf Research Farm at Gilbert, IA........................................................................................................................... .........6
Species and C u ltiv a r Friais
2000 High-Maintenance Kentucky Bluegrass Cultivar Trial....................................................................................................................................... 9
1999 Perennial Ryegrass Cultivar Trial....................................................................................................................................................................... 12
2(K) 1 Tall Fescue Cultivar Trial..................................................................................................................................................................................15
1998 Fine Fescue Cultivar Trial.................................................................................................................................................................................18
1998 Fairway Height Bentgrass Cultivar Trial........................................................................................................................................................... 20
1998 Green Height Bentgrass Cultivar Trial............................................................................................................................................................. 2 1
1999 Non-Irrigated Fairway Height Kentucky Bluegrass Cultivar Trial...................................................................................................................22
Shade Adaptation Study.............................................................................................................................................................................................. 23
Ornamental Grasses Project 2(XX)-2(X)2.......................................................................................................................................................................24
H erbicide and G ro w th R eg u lato r R esearch
2(X)3 Crabgrass Control Trial......................................................................................................................................................................................25
Selective Removal of Creeping Bentgrass from Kentucky Bluegrass....................................................................................................................... 27
Evaluation of plant growth enhancer (GABA - gamma aminobutyric acid) for Establishment of Aq rostís pa lusí ris Huds..................................... 30
Evaluation of plant growth enhancer (GABA - gamma aminobutyric acid) for Poa pratensis L. growth and sod establishment........................... 33
2003 Postemergence Annual Bluegrass Trial............................................................................................................................................................. 34
R o u n d u p Ready C reep in u B enturass R esearch
Timing of Roundup* Application Critical when Converting Golf Course Greens and Fairways to RoundupvReady Creeping Bentgrass............ 36
Benefits Evaluation of Poa annua Control in Roundup Ready" Creeping Bentgrass...............................................................................................38
Techniques for Conversion of Conventional Putting Greens to Roundup ReadyRCreeping Bentgrass................................................................... 39
Field Performance of Roundup Ready Creeping Bentgrass.......................................................................................................................................42
G enetics an d P lan t Physiology R esearch
Identification and characterization of CBF gene in perennial ryegrass (Lolium perenne L).....................................................................................44
Mapping of Quantitative Trait Loci (QTL) for Winter Hardiness in Perennial Ryegrass........................................................................................ 45
Analysis of Genetic Diversity in Rough bluegrass. Colonial and Velvet Bentgrasses Using RAPD Markers.........................................................46
Physiological Responses of Creeping Bentgrass to Mowing.....................................................................................................................................47
T u rfg ra ss Disease R esearch
Evaluation of Fungicides for Control of Dollar Spot and Brown Patch in Creeping Bentgrass - 2(X)3....................................................................48
Evaluation of Fungicides for Control of Dollar Spot in Creeping Bentgrass - 2(X)3.................................................................................................49
T u rfg ra ss N u tritio n R esearch
Nitrogen Deficiencies in Creeping Bentgrass can be Identified Through Remote Sensing......................................................................................50
Evaluation of Phosphorus Rate and Mixing Depth on the Growth and Establishment of Poa pratensis L. inSand-based Systems.........................53
Evaluation of Various Slow-releasc Nitrogen Sources for Growth and Establishment of Poa pratensisL.onSand-based Systems......................... 55
Cation Ratios and Soil Testing Methods for Sand-Based Golf Course Greens.........................................................................................................57
S p o rts-T u rf and T raffic S im ulation R esearch
Effect of plastic mulching on color retention on seeded Bermudagrass varieties during fall season........................................................................ 58
Bermuda Species Traffic Study..................................................................................................................................................................................60
Effect of soil moisture content and various traffic intensities on the performance of Kentucky bluegrass...............................................................62
Traffic tolerance of cool season seedling turf under simulated football traffic - Single seeding...............................................................................67
Traffic Tolerance of Cool Season Seedling Turf Under Simulated Football Traffic-Multiple Seeding T rial.......................................................... 69
Performance of Established Cool Season Grasses Under Simulated Football Traffic.............................................................................................. 71
E n v iro n m en tal R esearch
1991 Corn Gluten Meal Crabgrass Control Study - Year 13-2003............................................................................................................................ 73
1995 Corn Gluten Meal Rate Weed Control Study - Year 9-2003............................................................................................................................. 75
1999 Corn Gluten Meal/Urea Crabgrass Control Study - Year 5-2003.....................................................................................................................77
Field Assessment of Winter Injury on Creeping Bentgrass and Annual Bluegrass Putting Greens......................................................................... 79

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2000 High-Maintenance Kentucky Bluegrass Cultivar Trial
NickE. Christians and Rodney

John

The National Turfgrass Evaluation Project (NTEP) has sponsored several regional Kentucky bluegrass cultivar trials conducted at most
of the northern agricultural experiment stations. This trial was established in the fall of 2000. The area receives 4 lb N/1000 IT/yr and is
irrigated as needed. The objective of this study is to investigate cultivar performance under a high-maintenance cultural regime similar to
that used on irrigated home lawns in Iowa.
The visual quality was evaluated monthly in 2003 from May through October (Table 1). The values listed under each month in Table 1
arc the averages of visual quality ratings made on three replicated plots. Visual quality was based on a scale of 9 to 1 :9 = best quality. 6
= lowest acceptable quality, and 1 = worst quality. The yearly average of the monthly data for each cultivar was calculated and is listed
in the last column (Mean). The first cultivar listed in Table 1 had the highest average visual quality rating for the entire 2003 season.
The cultivars are listed in descending order by average quality. The last row states the LSD (least significant difference), which is a
statistical measurement of how widely the datum in each column must vary before they are considered to be different from one another.
Data for genetic color (Gen Color) and leaf texture (Leaf Tex) were also collected in June 2003. Genetic color was rated using a 9 to 1
scale with 9 = dark and 1 = light green. Leaf texture was assessed with a 9 to 1 scale with 9 = fine and 1 = coarse texture. Spring
greenup (Greenup) data were taken in April 2003 and were estimated using a 9 to 1 scale with 9 = green and 1 = dormant turf. In July
2003. damage from bluegrass billbugs w'as observed on several of the bluegrass cultivars. Some cultivars were undamaged. Ratings
were taken at that time and arc reported in Table 1. A rating of 9 is no damage and 1 is dead grass due to the feeding damage of the
billbugs.
Table 1. 2003 visual quality and other ratings for the High-Maintenance Kentucky Bluegrass Cultivar Trial
--------------------------- Visual Quality
BiJlbug
jun
May
Sep
Gen Color Greenup Leaf Tex Damage
Aug
Kentucky Bluegrass Cultivar
Jul
7.7
7.0
7.7
7.7
8.0
9.0
8.3
TSUNAMI (.1-2487)
7.3
5.3
7.7
6.7
6.7
8.3
7.7
BEDAZZLED
7.0
6.0
6.3
9.0
7.7
7.3
8.3
7.0
7.0
9.0
6.3
6.7
7.3
LANGARA
7.7
7.7
7.7
7.7
5.3
7.0
9.0
7.3
7.0
MIDNIGHT II (A98-739)
7.0
6.7
6.7
8.0
7.3
8.3
6.7
5.7
6.5
RUGBY II
7.0
8.0
7.7
5.0
9.0
6.7
7.3
7.3
7.3
J-1838
6.7
7.0
7.7
7.0
8.3
7.3
6.3
9.0
J-2561
5.0
SI A96-386
6.7
5.0
5.7
9.0
7.0
6.0
8.3
7.0
8.3
6.7
7.0
8.0
7.0
8.0
7.3
8.0
9.0
5.0
UNKNOWN
7.7
8.0
7.7
6.0
8.3
A97-1409
6.0
6.0
9.0
6.0
7.7
6.7
9.0
6.7
7.0
7.3
GINNEY (J-1368)
7.0
5.3
7.3
7.0
6.0
7.0
7.7
7.3
8.3
8.0
6.3
9.0
PST-161
7.7
7.7
9.0
6.7
6.0
7.3
5.7
6.3
A96-427
6.3
8.7
6.7
6.7
7.0
6.7
6.7
8.0
8.0
BAR PP 0566
6.7
7.0
7.0
7.7
7.0
7.3
8.3
6.0
6.3
8.7
BLUESTONE (PST-731)
6.7
7.7
8.0
5.7
6.0
8.0
7.0
6.3
9.0
MISTY
6.7
6.7
7.7
7.0
6.7
7.3
A97-1432
6.3
9.0
7.3
7.7
7.0
6.7
6.7
7.3
5.0
8.0
6.3
6.3
BEYOND (J-1880)
6.7
7.7
7.0
9.0
6.7
7.3
7.3
7.3
5.3
J-1513
6.7
7.0
6.7
7.0
8.0
J-2890
7.7
5.3
9.0
6.3
6.7
8.7
6.7
6.7
7.0
7.7
7.3
7.0
MIDNIGHT
6.0
7.7
7.0
8.0
7.0
7.7
4.3
7.0
9.0
6.3
NORTH STAR
7.7
7.7
SR 2284 (SRX 2284)
6.0
6.7
9.0
7.7
6.3
7.3
7.3
7.0
7.0
8.7
7.0
7.7
6.3
7.3
7.3
5.3
ARCADIA
7.0
7.0
5.7
7.7
8.7
6.3
7.3
BARRISTER (.1-1655)
7.0
5.7
6.7
7.3
7.7
7.0
7.3
GLENMONT (H94-293)
7.0
6.3
9.0
5.3
6.7
6.7
6.7
7.7
6.7
6.7
9.0
7.0
5.7
PST-B5-125
6.7
7.7
7.7
7.0
6.7
6.0
7.0
6.7
5.0
QUANTUM LEAP
6.7
7.0
7.7
7.7
7.0
9.0
7.0
CABERNET
7.0
6.3
6.7
7.0
7.0
6.7
5.0
7.7
7.3
7.3
7.3
ODYSSEY
7.7
6.7
7.0
8.7
6.7
7.0
7.7
6.0
6.3
PRINCETON 105
A97-1330
6.7
5.7
6.3
8.0
7.0
7.3
5.0
6.0
9.0
6.7
5.7
7.7
7.0
6.7
6.0
6.3
ASCOT
5.3
9.0
6.0
8.0
7.3
6.3
7.3
6.0
6.3
9.0
5.3
BOUTIQUE
5.7
7.7
6.0
H92-558
6.0
7.0
7.0
6.3
7.0
6.7
7.0
7.0
MALLARD (A97-1439)
5.7
6.0
8.3
6.3
7.3
7.0
7.3
7.7
9.0
6.7
7.0
6.7
6.3
7.3
5.0
6.3
NU DESTINY (.1-2695)
6.7
7.3
6.0
7.7
6.0
6.3
8.0
PST-YORK HARBOR 4
7.3
6.0
6.7
6.7
7.0
6.7
7.0
6.7
SERENE
7.0
6.0
8.3
6.7
8.0
5,7
7.0
6.3
6.7
6.3
9.0
6.0
A96-739
5.7
7.0
6.7
ARROW (A97-1567)
7.0
7.0
6.0
9.0
6.3
6.3
6.7
7.0
7.0
B3-171
6.7
8.3
6.3
6.3
6.3
6.3

9

Oct
8.3
8.0
9.0
8.0
8.3
8.3
8.3
8.3
7.7
8.3
8.3
8.0
8.3
7.7
7.3
7.3
8.0
8.3
7.7
8.0
7.7
7.3
6.7
7.3
8.3
6.7
8.0
8.3
7.3
7.3
6.3
7.0
8.0
8.3
8.7
6.7
7.3
7.0
7.7
6.7
7.7
7.3

Mean
7.9
7.6
7.6
7.6
7.6
7.5
7.5
7.5
7.5
7.4
7.4
7.4
7.3
7.3
7.3
7.3
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.1
7.1
7.1
7.1
7.1
7.0
7.0
7.0
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.8
6.8
6.8

Visual Quality

Kentucky Bluegrass Cultivar
BAR PP 0573
BLUE RIDGE (A97-1449)
DLF 76-9032
SHAMROCK
SHOWCASE
UNIQUE
A98-365
B3-185
BA 00-6001
BA 83-113
BARONETTE (BA 81-058)
BROOKLAWN
GOLDSTAR (A98-296)
H92-203
LIBERATOR
PP H 7832
PST-108-79
SRX 2394
WILDWOOD
B4-128A
BAR PP 0468
BODACIOUS
BORDEAUX
CHAMPAGNE
HALLMARK
LAKESHORE (A93-200)
MOONLIGHT
NA-K992
NUGLADE
PST-B3-170
PST-H6-150
RAM BO
ROY ALE (A97-1336)
BAR P P 0471
BH 00-6003
BLACKS I ONE
PP H 6370
PRO SEEDS - 453
A98-183
ABBEY
BARONIE
BARZAN
BRILLIANT
CHELSEA
CHICAGO II
EAGLETON
FREEDOM II
HV 238
IMPACT
JEWEL
MERCURY (PICK-232)
PP H 7907
PST-1701
RAVEN
SONOMA
SRX QG245
1B7-308
99AN-53
AWESOME (J-1420)
BA 82-288
BARON
BLACKSBURG II (PST-1BMY)
BLUE KNIGHT
MARQUIS
PST-H5-35
SRX 26351
A98-1028
A98-881

Gen Color
7.0
7.3
6.0
7.0
7.3
6.3
6.3
6.7
6.3
6.7
7.3
6.3
7.0
6.0
7.3
7.3
6.3
7.0
7.3
6.0
6.3
6.7
7.0
7.0
6.7
6.3
7.7
7.7
6.7
7.3
6.0
6.3
7.3
6.0
6.3
7.0
6.7
6.0
7.0
6.7
5.7
8.0
5.7
6.7
7.0
6.7
7.0
6.7
7.3
6.7
7.0
7.7
6.7
7.3
6.7
6.3
7.0
8.0
7.0
6.7
6.3
6.3
7.0
6.7
6.3
7.7
6.0
6.7

Greenup
6.0
6.3
5.3
7.0
5.3
5.0
6.0
5.7
5.3
6.3
6.3
6.3
6.0
5.0
4.7
6.3
5.7
6.0
5.3
5.0
5.7
6.0
5.7
6.7
5.0
6.3
6.3
6.3
5.0
5.3
6.0
6.3
5.3
6.0
5.0
7.0
5.7
6.3
5.7
6.0
5.7
4.7
5.3
6.0
5.3
7.0
5.0
7.0
5.3
6.3
6.7
5.7
7.3
6.3
6.0
6.7
6.7
6.0
5.0
6.3
5.3
5.7
5.0
6.3
5.3
5.7
6.0
6.0

Leaf Tex
6.0
6.3
7.3
6.3
6.7
6.3
6.3
6.3
6.3
6.0
6.7
6.3
6.0
6.7
6.3
6.0
6.3
6.7
7.7
6.7
7.3
6.3
7.0
6.7
7.7
7.0
5.7
6.7
6.7
7.3
6.0
7.0
6.3
7.0
6.3
6.3
7.3
6.7
6.0
6.0
6.7
7.0
6.7
7.3
6.3
6.0
7.0
6.0
7.3
6.7
6.7
6.3
7.3
6.3
6.7
7.3
6.0
6.3
6.7
6.3
6.3
6.7
6.7
6.3
6.7
7.7
6.7
7.0

io

Billing
Damage
9.0
8.7
9.0
9.0
9.0
9.0
9.0
9.0
9.0
7.7
9.0
7.7
9.0
9.0
9.0
8.0
6.7
9.0
7.0
8.7
9.0
8.7
9.0
9.0
9.0
9.0
9.0
9.0
8.7
9.0
9.0
9.0
8.7
8.0
9.0
5.7
7.3
7.3
9.0
7.3
8.0
7.3
9.0
9.0
6.7
9.0
6.3
9.0
7.7
8.0
6.7
7.3
8.7
8.0
8.0
8.7
7.3
9.0
7.0
9.0
9.0
8.3
8.7
8.0
8.7
7.0
8.7
9.0

May
6.7
6.7
6.3
6.0
7.3
6.0
5.7
6.0
6.0
6.3
6.3
6.0
5.7
6.7
6.3
5.7
6.3
5.7
6.0
6.3
6.7
5.7
5.7
5.7
5.7
6.3
6.3
5.0
5.7
6.3
5.7
6.3
5.7
6.0
5.7
6.3
6.0
6.3
6.0
5.7
6.0
5.0
5.7
6.3
7.0
6.3
7.0
6.0
6.7
5.3
5.7
5.3
5.7
5.3
5.7
5.7
5.3
5.3
7.0
5.7
6.0
6.3
5.7
5.3
6.0
6.0
5.7
6.0

Jun
6.3
6.3
6.7
6.7
6.3
6.3
5.7
6.3
6.0
6.3
6.3
6.0
6.7
6.0
5.7
5.7
6.3
6.0
6.0
6.0
6.0
5.0
6.3
7.0
6.3
6.0
6.0
6.7
5.7
6.3
5.7
6.3
6.7
6.3
5.7
5.7
6.0
5.7
6.0
6.3
6.0
6.7
5.7
6.0
6.0
6.7
6.7
7.0
6.7
6.3
5.3
6.0
6.3
6.0
6.3
6.7
5.7
6.0
6.0
6.0
5.7
6.3
6.3
6.0
6.3
7.3
6.3
6.3

Jul
7.3
6.7
7.0
7.0
6.7
7.7
7.0
7.0
7.7
6.3
7.7
6.7
7.0
7.3
7.0
7.0
6.0
7.7
7.0
7.7
7.0
6.0
7.0
7.7
7.0
7.0
6.3
7.0
6.7
7.3
7.3
7.0
7.0
7.3
7.0
6.3
6.0
6.3
7.3
7.3
6.7
7.0
7.0
7.3
5.3
7.0
6.3
7.0
5.7
7.0
6.0
6.0
7.3
7.3
7.0
7.7
6.7
7.0
6.0
7.3
6.0
6.7
6.0
6.3
6.3
6.3
6.7
6.7

Aug
7.0
6.7
6.0
6.7
7.0
6.3
7.0
7.0
7.0
6.3
6.7
6.3
6.3
6.7
6.7
7.7
6.3
6.7
6.7
6.3
6.3
7.3
6.3
7.0
7.0
6.3
5.7
6.7
6.3
6.7
6.3
6.0
6.0
7.0
7.0
6.3
7.0
5.3
6.0
6.7
6.7
7.0
6.3
7.0
6.3
6.3
5.7
6.7
5.3
7.0
6.0
6.7
6.3
6.7
6.7
7.0
6.3
7.0
5.7
6.3
6.7
6.0
6.0
6.7
5.3
5.7
6.3
5.7

Sep
6.7
7.7
6.7
7.3
6.7
6.7
7.0
7.0
6.3
7.7
6.7
7.3
6.7
6.7
7.3
7.3
8.0
6.0
7.3
6.7
6.7
7.3
6.7
6.3
6.3
6.7
7.7
7.3
7.7
7.0*
7.7
7.7
6.7
5.3
7.0
7.3
7.0
7.7
6.0
6.3
6.0
6.7
6.3
6.3
6.7
6.3
6.0
6.0
6.7
6.7
7.3
7.3
6.3
6.7
6.0
5.0
6.7
6.3
6.7
6.0
7.0
5.7
7.7
6.3
6.7
6.3
5.7
6.3

Oct
7.0
7.0
8.3
7.3
6.7
7.7
7.7
7.0
7.0
7.3
6.3
7.7
7.7
6.7
7.3
7.0
7.3
8.3
7.0
6.7
6.7
8.0
7.3
5.7
7.0
7.0
7.7
7.0
7.3
6.0
7.0
6.3
7.3
7.0
6.7
7.0
7.0
7.7
7.0
6.3
7.0
6.3
7.3
5.7
7.0
5.7
7.0
6.0
7.3
6.3
8.0
7.3
6.3
6.7
7.0
6.3
7.3
6.0
6.7
6.7
6.7
6.7
6.3
7.3
7.0
6.0
6.3
6.3

Mean
6.8
6.8
6.8
6.8
6.8
6.8
6.7
6.7
6.7
6.7
6.7
6.7
6.7
6.7
6.7
6.7
6.7
6.7
6.7
6.6
6.6
6.6
6.6
6.6
6.6
6.6
6.6
6.6
6.6
6.6
6.6
6.6
6.6
6.5
6.5
6.5
6.5
6.5
6.4
6.4
6.4
6.4
6.4
6.4
6.4
6.4
6.4
6.4
6.4
6.4
6.4
6.4
6.4
6.4
6.4
6.4
6.3
6.3
6.3
6.3
6.3
6.3
6.3
6.3
6.3
6.3
6.2
6.2

-Visual Quality—
Kentucky Bluegrass Cultivar
GOLDRUSH
J-2885
JEFFERSON
LILY
LIMOUSINE
PST-B4-246
RITA
ALPINE
B5-43
BLUEMAX (PST-B5-89)
BOOMERANG
ENVICTA
EXCURSION (1-1648)
PP H 7929
SRX2114
TOTAL ECLIPSE
A98-139
LIMERICK
A96-742
BH 00-6002
CHAMPLAIN (A98-1275)
DLF 76-9037
MONTE CARLO (A96-402)
PERFECTION (J-1515)
PST-1804
PST-222
ROYCE (A98-304)
VOYAGER II (PST-1QG-27)
WASHINGTON
A97-1715
APOLLO
DLF 76-9034
DLF 76-9036
EVEREST
EVERGLADE
FAIRFAX
KENBLUE
A98-407
ALLURE
AWARD
BARTITIA
CVB-20631
GO-9LM9
JULIA
PICK 417
SRX 27921
A96-451
HV 140
JULIUS
PST-604
A97-857
MOON SHADOW (PICK 113-3)
PP H 6366
B5-45
COVENTRY
PICK 453
CHATEAU
WELLINGTON
B5-144
BARIRIS
BA 84-140
BLUE SAPPHIRE (NA-K991)
BARITONE
LSD

Gen Color
7.0
7.7
5.7
6.7
6.7
6.7
7.3
6.7
7.0
7.7
7.7
7.3
7.7
6.7
6.3
7.0
6.7
7.0
5.7
6.0
6.3
5.7
6.7
7.3
7.0
7.0
6.7
7.0
6.0
6.7
6.3
5.0
6.3
7.3
7.0
6.3
5.3
6.7
6.0
7.0
6.3
6.7
5.7
7.0
7.0
6.3
7.0
7.0
6.0
6.3
7.0
6.7
7.0
6.3
5.7
7.0
5.7
5.7
7.3
7.0
7.7
8.0
6.7
1.4

Greenup
5.0
5.0
7.3
5.7
6.3
5.3
6.7
5.3
6.3
5.7
6.0
6.0
5.0
6.0
5.3
5.0
7.0
5.7
7.0
5.7
5.3
5.7
5.3
5.0
6.7
4.7
4.7
5.3
7.3
6.7
5.7
6.7
5.3
4.7
5.3
6.3
7.0
6.3
7.0
4.7
5.7
5.7
7.0
6.0
6.3
5.0
4.7
5.7
5.7
6.0
6.3
5.3
5.0
6.0
6.0
5.3
6.3
6.3
6.0
5.0
5.7
6.0
6.0
1.3

Leal Tex
6.3
6.3
7.0
6.7
6.7
7.0
6.3
7.7
6.7
5.7
7.0
6.3
6.0
6.0
7.0
6.7
6.0
6.7
6.3
6.3
6.0
6.3
6.0
6.3
6.7
5.3
7.3
7.0
8.0
7.0
6.3
6.0
6.0
7.0
6.7
6.7
8.0
6.0
6.7
6.3
7.0
6.3
8.0
6.7
5.7
6.7
5.7
6.0
6.3
6.0
7.3
6.7
7.3
6.0
6.7
6.0
6.0
7.3
6.3
6.3
5.7
6.0
5.7
0.9

Il

Billbug
Damage
8.3
8.0
8.0
8.0
6.0
8.3
8.3
6.0
6.0
9.0
6.0
7.3
7.3
8.0
9.0
6.0
8.0
6.7
9.0
9.0
7.3
9.0
9.0
7.3
7.3
7.0
8.7
9.0
8.7
8.0
9.0
8.7
8.3
7.0
6.7
8.0
7.0
7.7
4.7
8.7
5.7
7.3
6.3
6.3
6.3
5.0
6.7
5.7
6.0
6.7
7.7
5.3
5.7
6.0
5.0
6.7
5.7
8.0
5.0
5.0
5.7
5.3
5.0
3.8

May
5.3
6.7
5.7
6.0
6.0
5.3
6.0
5.3
6.0
6.0
5.7
5.7
5.7
5.3
6.0
6.3
5.3
5.7
5.7
6.0
6.3
6.0
6.7
5.3
5.0
5.3
5.7
5.0
5.3
5.7
5.7
5.7
5.0
6.0
6.3
6.0
4.7
5.3
5.7
5.3
6.0
5.3
5.0
5.0
5.7
6.0
5.7
5.0
5.7
5.7
5.3
6.0
6.0
6.0
6.0
5.3
5.7
4.3
6.0
5.3
5.3
5.3
4.7
1.4

Jun
6.0
6.0
6.0
6.3
6.3
6.0
7.0
6.3
5.7
6.3
6.0
6.0
6.3
5.3
6.0
6.3
5.7
6.3
5.3
6.3
6.3
5.7
5.3
6.3
6.3
5.7
5.7
6.0
6.3
5.7
5.7
5.3
5.0
5.3
6.3
6.0
6.0
5.3
6.0
5.3
6.0
5.3
5.7
6.3
5.7
5.3
5.0
5.7
6.0
5.7
5.7
5.3
5.7
5.3
6.0
5.3
5.3
4.7
5.0
4.7
5.3
5.3
4.0
1.8

Jul
6.3
6.3
6.7
6.7
5.3
7.7
6.7
6.0
5.0
5.7
4.7
5.7
5.3
6.3
7.0
4.7
5.7
6.0
7.3
7.3
6.0
6.3
5.7
5.7
6.3
6.3
6.0
6.0
6.7
5.7
6.7
6.0
6.0
5.3
4.7
6.3
6.0
5.3
4.3
5.3
6.0
5.7
6.0
5.0
5.7
5.0
6.3
4.7
5.3
5.3
5.3
5.0
5.0
5.3
4.3
5.0
5.3
5.0
4.3
4.7
4.3
4.7
2.7
3.1

Aug
6.0
5.7
6.7
6.0
6.3
5.7
6.0
6.0
6.0
5.7
6.0
6.7
6.0
6.0
5.3
5.3
6.0
6.3
6.3
5.7
6.0
6.0
6.0
6.0
5.7
5.7
6.0
6.3
6.3
5.7
6.3
6.3
7.0
5.3
5.7
4.7
6.3
6.0
5.0
5.3
4.7
5.3
6.3
6.3
5.0
5.0
5.3
5.3
5.0
5.3
5.7
4.3
4.7
5.3
4.0
4.7
4.7
5.7
4.7
5.0
4.3
5.3
3.0
4.0

Sep
6.7
6.3
6.3
5.7
6.3
6.0
5.7
6.3
6.3
6.3
7.3
6.7
5.7
7.0
5.7
6.3
6.7
6.0
5.0
4.7
5.0
5.7
5.7
5.7
6.0
6.3
5.7
6.3
5.7
5.7
4.7
5.3
6.3
6.3
6.0
6.0
6.0
6.0
6.7
6.0
5.7
6.0
5.7
6.0
6.0
6.0
5.7
6.3
5.3
5.3
5.3
5.3
5.3
4.7
5.0
5.0
4.0
5.7
4.0
4.7
4.3
4.0
3.3
3.7

Oct
6.7
6.3
6.0
6.3
6.7
6.3
6.0
6.7
7.3
6.7
7.0
5.7
7.3
6.3
6.3
7.3
6.7
5.7
5.7
5.7
6.0
5.7
6.3
6.7
6.3
6.0
6.3
6.0
5.3
6.3
6.0
6.0
5.3
6.3
6.0
6.0
6.0
6.0
6.3
7.0
5.7
6.7
5.7
5.7
6.0
7.0
5.7
6.7
6.0
6.0
5.3
6.3
5.3
4.7
5.3
5.3
5.0
4.7
5.3
5.0
5.0
4.0
3.7
3.2

Mean
6.2
6.2
6.2
6.2
6.2
6.2
6.2
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.0
6.0
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.8
5.8
5.8
5.8
5.8
5.8
5.8
5.8
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.6
5.6
5.6
5.6
5.4
5.4
5.3
5.2
5.1
5.1
5.0
5.0
4.9
4.9
4.8
4.8
3.6
1.9

1999 Perennial Ryegrass Cultivar Trial
Rodney A..

St.John and N. E. Christian

This was the fourth full year of the trial that began in the fall of 1999 with the establishment of 134 cultivars of perennial ryegrass at the
Iowa State University Horticulture Research Station. The study was established on an irrigated area that was maintained at a 2-inch
mowing height and fertilized with 3 to 4 lb N/1000 ft2/yr. The area received herbicide treatments as required.
The visual quality was evaluated monthly in 2003 from May through October (Table 1). The values listed under each month in Table 1
tire the averages of visual quality ratings made on three replicated plots. Visual quality was based on a scale of 9 to 1 :9 = best quality, 6
= lowest acceptable quality, and 1 = worst quality. The yearly average of the monthly data for each cultivar was calculated and is listed
in the last column (Mean). The first cultivar listed in Table 1 had the highest average visual quality rating for the entire 2003 season.
The cultivars are listed in descending order by average quality. The last row states the LSD (least significant difference), which is a
statistical measurement of how widely the datum in each column must vary before they arc considered to be different from one another.
Data for genetic color (Gen Color) and leaf texture (Leaf Tex) were also collected in June 2002. Genetic color was rated using a 9 to 1
scale with 9 = dark and 1 = light green. Leaf texture was assessed with a 9 to 1 scale with 9 = fine and 1 = coarse texture. Spring
greenup (Greenup) data were taken in April 2003 and were estimated using a 9 to 1 scale with 9 = green and 1 - dormant turf.
Tabic 1. 2003 visual quality and other ratings for the 1999 National Perennial Ryegrass Study.
.....................................Visual Quality
Jun
May
.lui
Aug
Sep
Gen Color Greenup Leaf Tex
Perennial Ryegrass Cultivar
6.0
7.0
6.3
8.7
9.0
8.0
7.3
9.0
APR 1232
8.7
7.7
PARAGON
9.0
7.3
6.0
9.0
7.3
5.3
5.7
6.7
6.3
9.0
8.0
9.0
7.3
BRJGHTSTAR SLT (PST-2A6B)
9.0
6.7
7.7
9.0
9.0
6.0
7.0
9.0
7.3
COURAGE (MB 410)
6.7
6.0
9.0
7.7
8.3
8.3
7.3
7.3
GATOR 3 (CIS-PR-85)
7.7
5.7
7.7
8.7
5.7
8.7
9.0
7.3
PST-2CRR
9.0
6.0
7.7
7.0
8.7
6.0
9.0
7.3
PST-2JH
8.0
7.7
6.0
8.0
7.3
PST-2LA
9.0
5.3
8.3
8.7
7.0
8.7
8.7
7.3
7.7
6.0
7.3
RACER 11 (PICK RC2)
8.7
7.7
7.7
6.0
6.7
9.0
5.3
9.0
SR 4220 (SRX 4801 )
9.0
6.0
ABT-99-4.560
8.7
8.3
7.3
7.3
7.3
4.3
8.7
7.0
5.7
9.0
8.0
7.3
5.3
8.3
PIZZAZZ
6.0
6.0
8.3
7.3
7.0
8.3
7.3
ABT-99-4.115
8.3
7.0
8.7
8.7
7.7
5.7
BLAZER IV (PICK MDR)
6.0
7.3
9.0
5.7
5.7
8.3
8.0
7.3
7.0
9.0
7.3
CAS-LP84
5.7
5.7
9.0
8.0
7.0
7.7
7.3
CATALINA
9.0
6.0
8.7
8.0
CHARISMATIC (LTP 98-501)
9.0
7.3
5.3
7.3
7.3
5.0
8.7
6.0
8.7
8.0
7.0
6.7
8.7
GRAND SLAM 2L96 (PST-2L96)
6.0
6.7
7.0
7.0
9.0
7.3
8.3
MONTEREY II (JR-187)
8.7
8.7
8.7
7.7
5.7
7.0
MPI 07
5.3
8.3
7.3
6.7
7.7
7.0
5.7
7.0
8.7
8.0
8.7
PARADIGM (APR 1236)
8.7
7.7
6.7
5.3
7.3
9,0
5.3
PINNACLE II (BAR 9 B2)
9.0
5.7
5.7
8.3
7.7
7.3
7.7
PREMIER II
7.0
8.3
7.7
5.7
7.0
9.0
8.7
5.3
8.3
7.3
PST-2RT
7.7
8.7
5.7
8.7
8.7
7.3
5.3
7.0
RADIANT
7.0
5.7
SEVILLE II
8.7
7.3
7.0
6.0
9.0
9.0
8.7
5.7
8.7
8,0
7.0
5.3
7.3
9.0
WILMINGTON
9.0
8.7
7.3
7.0
7.0
ABT-99-4.464
9.0
6.0
5.3
5.7
6.7
AFFIRMED
8.7
9.0
8.3
7.7
7.0
6.3
9.0
6.0
9.0
8.7
7.0
7.0
5.7
7.0
ALLSPORT
7.0
8.0
8.0
5.7
7.7
7.3
7.3
5.0
APR 1235
7.7
5.0*
6.0
8.0
7.0
CABO (CIS-PR-80)
7.3
8.3
9.0
5.7
8.7
7.0
7.3
5.3
9.0
9.0
7.0
INSPIRE ( R8000)
5.7
6.7
9.0
8.3
7.3
7.3
KOKOMO (CIS-PR-69)
9.0
5.3
7.7
7.7
6.7
MANHATTAN 3
5.0
9.0
8.3
9.0
5.3
6.0
9.0
7.0
9.0
8.3
7.3
7.3
5.3
PENNANT II
8.7
5.7
7.0
9.0
7.3
5.3
9.0
7.3
PROSPORT (AG-P981)
8.7
7.3
6.7
5.7
RENAISSANCE (APR 1233)
7.7
7.7
8.0
5.3
7.7
6.7
5.7
8.7
7.0
5.3
8.3
9.0
SUMMERSET (MB 413)
6.7
9.0
4.7
9.0
8.3
7.3
5.7
7.0
ABT-99-4.339
8.7
7.0
ABT-99-4.965
9.0
5.3
6.7
9.0
7.3
5.0
5.7
8.7
8.7
7.0
5.3
8.3
7.3
6.3
APR 1231
7.0
9.0
5.7
5.7
9.0
8.7
7.3
6.7
ARRIVAL (CIS-PR-84)
CATHEDRAL II
8.7
9.0
8.0
7.3
7.0
7.0
6.3
5.3
9.0
7.7
7.0
7.0
6.0
7.0
9.0
CHARGER II
5.3
5.7
8.7
8.7
7.0
7.0
5.7
6.7
9.0
CITATION FORE (PST-2BR)
6.7
DLF-LDD
5.0
8.3
8.3
7.3
7.3
5.3
8.3

12

Oct

Mean

8.7
9.0
8.7
8.7
9.0
8.7
8.3
8.7
8.7
8.7
8.7
8.7
8.3
8.0
9.0
8.7
8.7
8.3
8.7
8.7
8.7
8.7
9.0
8.3
8.3
8.7
8.3
8.0
8.3
8.3
8.7
8.7
8.3
8.3
8.3
8.7
8.3
8.7
8.3
8.3
7.7
8.7
8.0
8.3
8.3
8.3
8.3

7.7
7.7
7.6
7.6
7.6
7.6
7.6
7.6
7.6
7.6
7.5
7.5
7.4
7.4
7.4
7.4
7.4
7.4
7.4
7.4
7.4
7.4
7.4
7.4
7.4
7.4
7.4
7.3
7.3
7.3
7.3
7.3
7.3
7.3
7.3
7.3
7.3
7.3
7.3
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2

■ Visual Quality

Perennial Ryegrass Cultivar
GALLERY (MB 412)
ICON (MB 414)
IQ (CIS-PR-75)
MACH 1 (ROBERTS-627)
MP88
PICK EX2
PICK PR QH-97
PST-2M4
QUEST II (ABT-99-4.721)
SR 4500
ABT-99-4.600
ADMIRE (JR-151)
ASCEND
CALYPSO II
CRUISER (ABT-99-4.709)
DIVINE
DP LP-1
ELEKIN
EXACTA
HAWKEYE (SRX 4RHT)
MPI 03
PALMER III
PLEASURE XL
PROMISE
PST-2SBE
RACER
SKYHAWK
SPLENDID (MB 411)
SR 4350 (APR 1237)
SR 4420 (SRX 4820)
STELLAR (CIS-PR-72)
AMAZING (Bl)
APR 1234
BRIGHTSTAR II
DAZZLE (AB I -99-4.724)
FIESTA 3
JIM 28
LINE DRIVE
MANHATTAN 4 (PST-2CRL)
PENTIUM (NJ-6401 )
SALINAS (PST-2SLX)
SUN KISS ED (ABT-99-4.834 )
ABT-99-4.815
BARLENNIUM
CATALINA II (PST-CATS)
CHURCHILL
JET
LPR 98-144
LTP-ME
MAJESTY
MDP
MEPY
PACESETTER (6011)
PANTHER
PASSPORT
PHANTOM
PICK PR 1-94
PREMIER
SECRETARIAT
SRX 4120
AFFINITY
ALL STAR2 (CIS-PR-78)
BUCCANEER
EP53
EXTREME (JR-317)
KOOS R-71
NEXUS
TERRADYNE (A5C)
BY-100
EDGE
PICK PRNGS

Gen Color

Greenup

I,eaf Tex

May

Jun

Jul

Aug

Sep

Oct

Mean

8.7
8.3
8.7
9.0
8.3
9.0
8.7
8.7
9.0
9.0
8.7
8.7
8.0
8.3
9.0
8.3
8.3
8.7
8.7
8.7
9.0
8.3
8.7
9.0
8.7
8.3
9.0
9.0
8.0
8.7
9.0
9.0
8.7
9.0
9.0
8.7
8.7
9.0
9.0
8.3
8.3
8.7
8.7
8.0
8.7
8.0
8.7
9.0
8.3
8.3
8.3
7.7
9.0
8.3
8.3
9.0
8.0
8.3
8.7
8.7
8.0
9.0
8.0
8.3
9.0
8.3
8.7
9.0
8.7
8.7
8.7

6.0
7.0
4.7
5.3
5.7
7.0
6.3
5.7
3.3
6.3
4.7
6.0
5.7
6.0
5.3
5.7
6.3
6.3
5.0
5.0
6.0
6.0
5.7
5.3
5.0
6.3
4.7
6.7
5.3
5.3
5.0
5.0
5.0
6.3
5.0
4.7
6.0
6.0
5.0
6.0
4.7
5.7
5.7
7.0
5.0
5.3
4.3
6.7
5.3
5.7
4.7
6.0
6.0
6.3
6.7
6.7
6.3
5.3
5.3
6.7
5.3
5.7
7.0
3.7
6.7
5.7
5.0
4.7
7.0
5.3
6.0

8.7
8.7
8.3
9.0
9.0
8.7
8.7
8.7
9.0
9.0
8.7
8.7
8.3
8.7
9.0
9.0
9.0
9.0
8.7
8.3
9.0
9.0
9.0
8.7
9.0
8.3
8.7
8.7
8.3
9.0
8.3
9.0
9.0
9.0
8.3
8.3
9.0
8.7
9.0
9.0
9.0
8.7
8.7
9.0
8.7
8.7
9.0
8.7
8.7
8.7
9.0
7.7
9.0
9.0
9.0
8.7
8.7
8.7
8.7
8.7
8.3
9.0
8.3
8.7
9.0
8.7
8.7
8.7
9.0
8.7
9.0

8.0
7.7
8.3
9.0
8.0
9.0
8.7
8.7
8.3
9.0
8.3
8.3
7.7
8.0
8.0
8.0
8.0
8.0
7.3
8.3
8.0
8.3
8.0
8.0
8.3
8.0
7.7
8.3
7.7
8.0
8.7
8.3
8.0
8.3
8.3
7.7
7.7
8.3
8.3
7.3
8.0
8.3
7.7
7.3
7.3
7.7
7.38.7
8.0
8.0
8.0
7.7
8.3
8.3
8.0
7.7
8.0
8.0
8.3
8.0
7.3
8.3
8.0
7.7
7.3
8.7
7.7
8.7
7.7
7.7
7.7

7.3
7.0
7.0
7.3
7.0
7.3
7.0
7.3
7.0
7.0
7.7
6.7
6.7
7.0
7.0
6.7
7.3
7.0
6.3
7.3
6.5
7.3
7.0
7.0
7.3
7.0
7.0
7.3
7.0
7.0
7.0
7.0
7.3
6.7
7.0
7.0
6.7
7.0
7.0
7.0
6.7
7.0
7.0
6.3
7.0
7.0
7.0
6.7
6.3
6.3
7.0
6.7
7.0
7.0
6.7
6.3
7.0
7.3
6.7
7.0
6.7
7.0
6.7
6.7
7.0
7.3
6.7
6.7
6.3
6.7
7.0

7.3
7.3
7.0
6.7
7.0
7.0
7.3
7.0
7.3
7.0
7.3
7.0
7.3
7.3
7.3
6.7
6.7
7.0
7.0
7.3
7.0
7.3
7.0
7.0
7.0
6.3
7.0
7.0
7.3
6.3
7.3
6.7
6.7
7.0
7.0
6.7
6.7
6.7
6.7
6.7
7.0
7.3
7.0
7.0
7.0
7.3
7.0
7.0
7.3
6.7
7.0
7.0
7.0
7.0
6.7
6.7
7.0
6.7
7.0
7.0
6.7
7.0
6.7
6.7
6.7
6.3
6.7
6.7
6.3
6.0
6.0

5.7
5.7
5.7
5.3
6.0
6.0
5.3
5.3
5.7
5.7
5.3
5.3
5.0
5.7
5.7
5.7
5.7
5.7
5.7
5.0
5.5
5.7
5.0
5.7
5.3
6.0
6.0
5.7
5.3
5.0
5.7
5.3
5.3
5.3
5.7
5.3
5.7
5.3
5.3
5.3
5.7
5.7
5.0
5.7
5.0
5.0
5.7
5.3
5.3
5.3
5.3
5.7
5.0
5.3
5.3
5.3
5.3
4.7
5.3
5.3
5.7
4.7
5.7
5.0
5.7
5.3
5.0
5.0
5.3
5.3
5.3

7.0
7.3
7.0
6.7
7.0
6.7
6.7
6.7
7.0
6.7
6.3
6.7
7.3
7.0
6.7
7.3
7.0
7.0
7.7
6.7
7.0
6.3
7.0
7.0
7.0
7.0
6.7
6.7
6.7
7.3
6.7
6.7
6.7
6.7
6.3
6.7
7.0
6.7
6.7
7.0
6.3
6.3
7.0
6.7
7.0
6.7
6.7
6.7
6.7
7.0
6.7
6.7
6.3
6.3
6.3
7.0
6.3
6.7
6.3
6.7
6.7
6.7
6.7
6.7
6.3
6.3
6.7
6.7
6.7
7.0
6.7

7.7
8.3
8.3
8.0
8.3
7.3
8.3
8.0
8.0
8.0
7.7
8.3
8.7
7.7
7.7
8.3
8.0
7.7
8.3
8.0
8.5
7.7
8.3
8.0
7.7
8.3
8.0
7.7
8.7
8.7
7.3
8.0
8.0
8.0
7.7
8.7
8.3
8.0
8.0
8.7
8.3
7.3
7.7
8.3
8.3
8.0
8.0
7.3
7.7
8.0
7.7
8.0
7.7
7.7
8.3
8.3
7.7
8.0
8.0
7.7
8.0
7.3
7.3
8.0
8.0
7.0
8.3
7.0
7.7
7.3
7.3

7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.2
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.1
7.0
7.0
7.0
7.0
7.0
7.0
7.0
7.0
7.0
7.0
7.0
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.8
6.8
6.8
6.8
6.8
6.8
6.8
6.8
6.7
6.7
6.7

13

Y isuai Quality

Perennial Ryegrass Cultivar
PROXY ME (A BT-99-4.625 )
SUPERSTAR (EP57)
APR 776
DP 17-9069
EPD
HEADSTART
LPR 98-143
PROWLER (APR 777)
WVPB-R-82
YVVPB-R-84
APPLAUD (PENNINGTON-11301 )
YATSUGREEN
PICK PR B-97
DP 17-9391
LINN
DP 17-9496
LSD

Cien Color

Greenup

Leaf Tex

May

Jun

Jul

Aug

Sep

Oct

Mean

8.3
8.7
8.7
7.3
8.3
8.7
8.3
7.7
8.0
8.0
9.0
8.0
9.0
6.7
7.3
7.0

5.3
6.3
5.3
4.3
5.7
6.3
5.0
5.0
6.3
4.7
5.3
4.3
5.3
4.3
4.0
2.0
2.3

8.3
8.3
8.7
8.3
8.7
9.0
8.0
8.0
9.0
8.7
9.0
9.0
8.7
7.7
7.7
7.7

7.7
8.0
7.7
7.3
7.3
7.0
7.7
7.7
7.7
7.3
8.0
7.3
7.7
6.0
6.7
6.0
1.8

6.3
7.0
6.7
6.7
7.0
6.7
6.7
6.7
7.0
6.0
6.7
7.0
6.7
5.7
5.7
5.7
1.3

6.7
5.3
7.0
5.0
5.7
6.3
6.3
5.0
7.3 , 4.3
6.7
5.0
6.7
4.7
6.7
4.7
6.3
4.7
6.0
5.3
6.0
7.0
6.3
4.3
4.7
5.0
6.0
4.7
4.0
5.3
5.3
3.7
~>2
2.2

6.7
6.3
6.3
6.7
6.3
6.7
6.7
6.7
6.7
6.7
4.0
6.7
6.3
6.0
5.7
5.7
2.4

7.7
7.0
7.0
7.7
7.3
7.7
7.0
7.0
7.0
8.0
7.3
7.0
7.7
6.7
6.0
6.3
1.8

6.7
6.7
6.6
6.6
6.6
6.6
6.6
6.6
6.6
6.6
6.5
6.4
6.3
5.8
5.6
5.4

1.1

l.l

14

1.0

2001 Tall Fescue Cultivar Trial
Shui-zhang

Fei and RodneSt. John

This is the second full year of the tall fescue trial that was established in September 2001 and is part of the National Turfgrass Evaluation
Program (NTEP). Similar trials are being conducted at many different locations around the US. The purpose of this trial is to evaluate the
regional adaptation of 160 tall fescue cultivars under non-irrigated conditions with 2 lbs N / l 000 ft2 per year and a mowing height of 2.53.5”.
The visual quality was evaluated monthly in 2003 from May through October (Table 1). The values listed under each month in Table 1
are the averages of visual quality ratings made on three replicated plots. Visual quality was based on a scale of 9 to 1: 9 - best quality, 6
- lowest acceptable quality, and I = worst quality. The yearly average of the monthly data for each cultivar was calculated and is listed
in the last column (Mean). The first cultivar listed in Table 1 had the highest average visual quality rating for the entire 2003 season.
The cultivars are listed in descending order by average quality. The last row states the LSD (least significant difference), which is a
statistical measurement of how widely the datum in each column must vary before they are considered to be different from one another.
Data for genet ic color (Gen Color) and leaf texture (Leaf Tex) were also collected in June 2003. Genetic color was rated using a 9 to 1
scale with 9 = dark and I = light green. Leaf texture was assessed with a 9 to 1 scale with 9 = fine and 1 = coarse texture.
Table 1. 2003 Visual ratings on turfgrass genetic color, spring greenup, leaf texture and quality, for the 2001 Tall Fescue Cultivar Trial.
---------------------------- Visual Quality-----------------------Tall Fescue Cultivar
Gen Color Greenup Leaf Tex
Jun
Mean
Jul
Aug
Sep
May
Oct
7.7
DA VINCI (LTP-7801)
6.7
6.7
7.0
7.0
6.8
6.3
7.7
6.3
7.3
6.0
7.0
8.0
6.7
6.7
6.7
7.3
6.7
6.7
6.3
JUSTICE (RB2-01)
TITAN LTI).
6.7
6.7
6.7
6.7
6.3
7.0
7.0
6.3
6.3
7.0
6.7
8.0
BAR FA 1005
7.0
6.0
6.0
6.7
7.7
6.7
6.6
6.3
6.7
6.7
6.7
GRANDE II
7.3
8.0
7.0
6.6
6.3
6.3
6.3
8.0
6.6
JAGUAR3
7.0
6.7
6.7
6.7
6.7
6.7
6.3
6.3
8.0
7.0
6.0
6.7
6.7
6.7
6.7
6.6
6.3
MUSTANG 3
6.3
8.0
6.7
6.7
7.0
6.7
6.6
6.0
6.7
PICASSO
6.3
6.3
PICK TF 11-97
7.0
6.3
7.0
6.3
6.7
6.3
7.0
7.0
6.3
6.6
6.7
6.7
SILVERADO II (PST-578)
6.0
7.0
7.3
6.7
6.6
6.3
6.3
6.3
6.4
7.0
6.0
7.0
6.3
6.3
6.3
6.0
7.0
6.7
01-TFOR3
ATE 704
5.7
6.4
7.0
7.0
6.0
6.3
6.7
7.0
6.3
6.3
7.7
6.4
5.7
6.7
COCHISE III (018)
6.0
7.7
6.3
6.3
6.3
7.3
6.4
6.0
7.7
7.0
DP 50-9082
7.3
6.3
6.3
6.7
6.0
6.3
FALCON IV (F-4)
6.7
6.7
6.7
6.4
7.0
6.3
7.0
6.0
6.0
6.3
GO-FL3
7.0
6.4
7.0
6.7
6.7
6.3
6.3
6.3
6.3
6.3
6.4
MILLENNIUM
7.0
6.7
6.7
6.3
7.0
6.0
6.0
7.0
6.3
UT-155
7.0
6.0
6.7
6.4
7.0
7.0
6.3
6.3
6.3
6.3
2ND MILLENNIUM
7.0
7.7
6.3
6.3
6.0
6.3
6.0
7.3
6.3
6.3
7.0
7.0
6.7
6.0
6.0
ATI-803
6.3
6.3
6.3
6.3
6.3
BLACKWATCH (PICK-OD3-01)
7.7
8.0
6.0
6.7
6.3
6.3
6.0
6.0
6.3
6.3
7.7
BRAVO
6.0
7.0
6.3
6.0
6.0
6.3
6.3
6.0
7.3
FINELAWN ELITE (DLSD)
7.0
7.0
6.3
6.3
6.3
6.3
6.0
6.3
6.3
6.3
FINESSE II
8.0
5.7
8.0
6.0
6.3
6.7
6.3
6.3
6.3
6.3
8.0
FOCUS
6.7
6.0
6.0
6.3
6.3
6.3
6.3
6.3
6.3
8.0
LEGITIMATE
6.0
6.7
6.3
7.3
6.3
6.3
6.3
6.3
6.3
MA 127
6.7
7.0
6.3
7.7
6.0
6.0
6.3
6.3
6.3
6.3
PST-5BZ
7.7
6.0
7.0
6.3
6.3
6.7
6.0
6.3
6.3
6.3
6.7
6.7
PST-5S12
7.0
6.3
7.0
6.0
6.0
6.3
6.3
6.3
QUEST
8.0
7.0
6.0
7.0
6.0
6.0
6.0
6.3
6.3
6.3
R-4
7.0
6.0
6.7
6.0
8.0
6.3
6.3
6.3
6.3
6.3
9.0
5.7
6.7
6.7
6.3
6.0
TAR HEEL
6.0
6.3
6.3
6.3
TAR HEEL II (PST-5TRI)
7.0
6.7
6.7
6.3
6.3
7.0
6.0
6.3
6.0
6.3
TITANIUM (SBM)
6.7
7.0
6.3
7.0
6.0
6.0
6.3
6.3 ' 6.3
6.3
5.7
8.0
6.0
6.3
6.3
6.3
6.3
6.0
6.3
UT-RB3
6.3
8.0
6.7
ATF-800
6.0
6.0
6.2
6.7
6.0
5.3
6.0
6.3
BARLEXAS
7.7
6.7
6.2
6.0
7.0
6.0
6.7
6.0
6.0
6.0
8.0
6.7
7.0
6.0
6.0
6.0
6.7
6.2
BARLEXAS II
6.3
6.3
BONSAI
7.0
6.0
7.0
6.0
6.0
6.0
6.3
6.3
6.2
6.3
CIS-TF-64
7.7
7.0
6.0
6.0
6.0
6.0
6.0
7.0
6.3
6.2
6.7
5.7
5.7
6.2
COYOTE
7.3
6.0
7.0
6.3
6.3
6.3
DOMINION
6.2
7.0
6.0
6.0
6.7
6.0
6.7
6.0
6.3
6.3
DP 50-9226
7.0
6.0
7.0
6.2
6.7
5.7
6.3
6.3
5.7
6.3
7.0
6.0
6.2
INFERNO (JT-99)
6.3
7.0
6.3
6.3
6.3
6.0
6.3
K01-E09
6.2
8.0
6.0
7.0
6.0
6.3
6.3
6.0
6.3
6.3
MRF211
8.0
6.0
7.0
6.0
5.7
6.0
6.0
7.0
6.3
6.2
MRF 25
7.7
6.2
6.3
7.0
6.0
6.3
6.3
6.0
6.3
6.3
PADRE (NJ4)
5.7
7.0
7.7
6.0
6.3
6.0
6.0
6.7
6.3
6.2

15

Tall Fescue Cultivar
PICK-00-AFA
RAPTOR (CIS-TF-33)
REBEL SENTRY
REMBRANDT
SCORPION
SII;VERSTAR (PST-5ASR)
SOUTHERN CHOICE II
TEMPEST
WYATT
01-ORU1
B-7001
BAR FA 1003
BEI
CIS-TF-65
CONSTITUTION (ATF-593)
ELISA
ENDEAVOR
FIVE POINT (MCN-RC)
GO-RD4
MA 138
OLYMPIC GOLD
PLANTATION
PST-57E
PST-5BAB
PST-5T1
REBEL EXEDA
RIVERSIDE (PROSEEDS 5301)
ROBERTS SM4
SR 8250
SR 8600
TOMAHAWK RT
BINGO
CASED
C1S-TF-60
CIS-TF-67
DLF-J210
FORTE (BE-2)
PST-5A1
PST-5FZD
PST-5LO
BARRINGTON
COVENANT (A I F 802)
DAYTONA (MRF 23)
FALCON II
GREMLIN (P-58)
JF-6
JTTFF-2000
KOI-8007
LANCER
MA 158
MASTERPIECE
MRF 210
MRF 27
MRF 28
PST-DDL
SR 8550 (SRX 8BE4)
SRX 805
TAHOE (CAS-157)
TULSA II (AIT 706)
TURBO (CAS-MC1)
WOLFPACK
ATF 702
AVENGER (LIZ)
CAYENNE
EA 163
GUARDIAN-21 (ROBERTS DOL)
JT-12
JT-13
LARAMIE
MAGELLAN (OD-4)
MATADOR

Gen Color

Greenup

Leaf Tex

May

Jun

Jul

6.7
7.0
8.0
7.0
7.0
7.7
7.0
7.7
7.0
7.7
7.7
7.0
7.0
7.7
8.3
6.7
7.7
7.3
8.0
7.3
7.3
7.7
7.7
7.0
7.0
8.0
8.0
7.7
7.7
7.0
8.0
7.7
7.0
7.7
7.0
7.0
7.7
7.0
7.0
7.7
8.0
8.0
7.0
7.0
7.7
8.0
8.0
7.7
8.0
8.0
7.0
8.7
8.0
7.0
8.0
8.0
7.7
8.0
7.3
7.0
7.0
8.0
7.0
7.0
7.7
7.0
8.0
7.0
8.0
8.0
8.0

6.0
6.0
6.0
6.3
5.7
6.0
6.0
6.0
6.0
6.3
6.3
6.0
6.0
6.0
5.7
6.7
6.0
6.3
6.0
6.0
6.3
6.3
6.0
6.0
6.3
6.3
6.7
6.3
6.3
6.0
6.0
6.0
6.3
6.3
6.3
6.0
6.0
6.0
6.3
6.3
6.0
6.3
6.0
6.7
6.0
6.0
6.0
5.7
6.7
6.3
6.7
6.0
6.3
6.3
6.0
6.3
6.0
6.0
6.0
6.7
6.0
5.7
6.0
6.3
6.3
6.3
6.0
6.7
6.0
6.0
6.0

7.7
7.0
6.7
7.0
6.3
7.0
7.0
6.0
8.0
7.0
7.0
7.0
7.0
7.0
7.0
7.0
7.0
7.0
7.0
6.0
7.0
6.3
8.0
7.0
7.0
7.0
8.0
7.7
7.0
6.0
6.0
7.7
6.0
7.0
7.0
6.7
7.7
7.0
7.7
6.0
6.7
7.3
6.7
6.7
6.0
7.0
7.0
7.0
7.7
6.3
7.0
6.3
7.3
7.0
7.0
7.3
7.0
6.0
6.3
6.0
7.0
7.0
7.0
7.0
7.0
7.0
8.0
7.0
7.0
7.0
7.0

6.3
6.0
6.0
5.7
6.0
6.0
6.0
6.0
6.0
6.0
6.0
5.7
6.0
6.0
6.0
6.3
5.7
6.0
6.0
6.0
5.7
6.0
5.7
5.7
6.0
5.7
5.7
5.7
6.0
6.0
6.0
5.7
5.7
5.7
5.7
5.7
5.7
6.0
5.7
6.0
5.7
5.7
5.7
5.7
5.7
6.0
5.7
5.7
5.7
5.7
6.0
6.0
5.7
5.7
5.7
5.3
5.7
5.7
5.7
6.0
5.7
5.7
6.0
5.7
5.7
5.7
5.3
5.7
5.7
5.7
5.7

6.0
6.3
6.0
6.0
6.0
6.0
6.0
6.0
6.0
6.3
6.3
6.3
6.0
6.3
5.7
6.0
6.0
6.7
6.0
6.0
6.0
6.0
6.0
6.0
6.0
6.0
5.7
6.0
6.3
6.3
6.0
6.3
6.3
6.3
6.3
6.7
6.3
6.0
6.0
6.0
6.3
6.0
6.0
5.7
6.0
5.7
5.7
5.7
6.0
5.7
6.0
5.7
6.0
6.0
6.0
5.7
5.7
6.0
5.7
5.7
6.0
5.7
5.7
5.7
6.0
5.7
6.0
5.7
5.7
6.0
5.7

6.0
6.0
6.3
6.3
6.0
6.0
6.7
6.3
6.0
6.0
5.7
6.0
6.0
6.0
6.7
5.7
6.3
5.7
6.0
6.3
6.0
6.0
6.0
6.0
6.0
6.0
6.0
6.0
6.3
6.3
6.0
6.0
6.0
6.0
6.3
6.0
6.0
6.0
6.0
6.0
6.0
6.3
6.3
6.0
6.0
6.0
6.0
6.0
5.7
6.0
6.0
5.7
6.0
6.0
6.0
6.0
6.0
6.0
6.0
6.0
5.7
6.0
5.7
6.0
6.0
5.7
6.0
5.7
6.0
5.7
6.0

16

Visual Quality
Sep
Aug

Oct

Mean

6.3
6.7
7.0
6.3
6.7
6.0
6.3
6.3
6.7
6.0
6.7
6.0
6.3
6.0
6.7
6.7
6.0
6.0
6.0
6.0
6.0
6.0
6.7
7.0
6.7
6.3
6.3
7.0
6.0
5.3
6.7
6.3
6.0
6.0
5.7
5.7
6.3
6.0
5.7
6.0
6.0
5.3
6.0
6.0
6.0
6.7
6.0
6.7
6.0
6.7
6.0
6.3
6.0
6.0
6.3
6.3
6.7
6.0
6.0
6.0
6.0
6.0
6.0
6.0
5.7
6.0
5.7
6.3
6.3
6.7
6.0

6.3
6.3
6.0
6.3
6.3
6.3
6.3
6.0
6.0
6.3
6.0
6.3
6.0
6.0
6.0
6.0
6.3
6.0
6.0
6.0
6.3
6.3
6.3
6.0
6.0
6.3
6.7
6.0
6.3
6.7
6.3
6.3
6.3
6.3
6.3
6.3
6.0
6.0
6.3
6.0
6.0
6.3
6.3
6.3
6.0
5.7
6.0
6.0
6.3
6.0
6.0
6.0
6.0
6.0
5.7
6.0
6.0
6.0
6.0
6.0
6.3
6.0
6.0
6.0
6.0
6.0
6.0
6.0
5.7
5.3
6.0

6.2
6.2
6.2
6.2
6.2
6.2
6.2
6.2
6.2
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.1
6.0
6.0
6.0
6.0
6.0
6.0
6.0
6.0
6.0
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.9
5.8
5.8
5.8
5.8
5.8
5.8
5.8
5.8
5.8
5.8

6.0
6.0
5.7
6.3
6.0
6.7
6.0
6.3
6.3
6.0
5.7
6.0
6.0
6.3
5.3
6.0
6.3
6.0
6.3
6.0
6.7
6.0
6.0
6.0
6.0
6.0
6.0
5.7
5.7
6.0
5.7
5.3
5.7
5.7
5.7
5.7
5.7
6.0
6.3
6.0
5.7
6.0
5.3
6.0
6.0
5.7
6.0
5.7
6.0
5.3
5.7
5.7
5.7
5.7
5.7
6.0
5.7
5.7
6.3
5.7
5.7
5.7
5.7
5.3
5.7
5.7
6.0
5.3
5.7
5.7
5.7

Tall Fescue Cultivar
PROSPECT
PST-5KI
RENDITION
STETSON
T991
WATCHDOG
01-RUTOR2
BILTMORE
CIS-TE-77
JT-18
JT-9
K0I-E03
MRF 26
PST-5JM
PST-5KU
PST-5NAS
TRACER
ATE 586
ATF 707
ATE 799
K01-WAE
KITTY HAWK 2000
TE66
BARI A 1CR7
BARRERA
DYNASTY
GO-SIU2
ATE 806
GO-OD2
KOI-8015
NA-TDD
PICK ZMG
PST-5TUO
SOUTH PAW (MRE 24)
JT-15
KALAHARI
PURE GOLD
SIGNIA
PST-53T
MRE 29
KY-31 E+
LSD

-Visual Quality—
Aug
Sep

Gen Color

Greenup

Leaf Tex

May

Jun

Jul

7.7
8.0
7.0
7.0
8.0
7.7
7.7
7.0
7.0
7.7
8.0
7.0
8.0
7.0
8.0
7.7
8.0
7.7
8.0
7.7
7.0
7.0
8.0
7.3
7.7
7.0
7.7
8.0
6.0
8.0
7.0
8.0
7.0
8.0
8.0
8.0
8.0
7.3
8.0
8.0
6.0
0.5

6.3
6.3
6.0
6.7
6.0
6.3
6.0
6.3
6.0
6.0
6.0
6.3
6.0
6.0
6.0
6.3
6.3
6.0
6.0
5.7
5.7
6.0
6.0
6.3
5.7
6.7
6.3
6.0
6.7
6.0
6.0
6.0
6.0
5.7
6.3
6.3
5.7
5.3
5.7
6.0
7.0
1.4

7.0
7.0
7.0
7.0
6.3
6.0
7.0
7.0
7.0
7.3
7.7
7.7
7.0
7.0
7.0
7.7
7.0
7.0
6.7
7.0
7.0
6.7
6.3
7.0
7.0
7.0
6.0
7.0
7.0
7.3
7.3
7.0
7.0
7.0
8.0
7.0
7.0
7.0
7.7
7.0
5.0
0.6

5.7
5.7
5.7
6.0
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.3
5.7
5.3
5.0
5.3
5.7
5.7
5.3
5.3
5.7
5.0
5.3
5.3
5.3
5.3
5.0
5.7
5.3
5.3
5.0
5.0
5.0
5.0
4.7
5.0
4.7
1.2

5.7
5.7
6.0
5.7
5.7
5.7
5.3
6.0
5.7
5.7
6.0
5.7
5.7
5.7
6.0
5.7
5.3
5.7
5.7
5.7
5.7
5.3
5.3
5.3
5.7
5.3
5.3
5.0
4.7
5.3
5.3
5.3
5.3
5.0
5.3
5.7
4.7
5.0
5.0
5.0
4.3
1.9

5.7
5.7
6.0
5.7
6.0
6.0
5.7
5.7
5.7
5.7
5.7
5.7
5.7
6.0
5.7
5.7
5.7
5.3
6.0
5.7
5.7
5.7
5.7
5.7
5.7
6.0
6.0
5.0
5.7
5.7
5.3
5.3
5.3
5.7
5.3 •
5.0
5.3
5.3
5.0
5.0
4.0
1.3

17

6.0
5.3
5.7
5.7
5.3
5.7
6.0
5.3
5.3
5.3
5.7
5.3
6.0
5.3
5.3
5.3
5.7
5.3
5.0
5.7
5.0
5.3
5.7
5.0
5.0
5.3
5.0
5.3
5.0
5.0
5.0
5.0
5.3
5.3
5.3
5.0
5.0
5.0
5.0
5.0
4.7
2.5

6.0
6.7
6.0
6.0
6.0
6.0
6.3
5.3
6.3
6.0
5.3
6.3
5.3
5.7
5.0
6.0
6.0
6.0
6.0
5.3
6.0
5.7
6.0
6.0
5.7
6.0
5.3
6.0
6.0
5.7
6.0
5.7
5.3
6.0
5.3
5.3
6.0
5.7
5.3
5.0
5.3
0.9

Oct

Mean

6.0
5.7
5.7
6.0
6.0
6.0
5.3
6.3
5.7
6.0
5.7
5.7
5.7
6.0
6.3
6.0
5.7
5.7
5.7
6.0
5.7
6.0
5.3
5.7
5.3
5.3
6.0
5.7
6.0
5.3
5.7
5.7
5.7
5.3
5.3
5.7
5.7
5.7
5.3
5.0
4.7
1.4

5.8
5.8
5.8
5.8
5.8
5.8
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.7
5.6
5.6
5.6
5.6
5.6
5.6
5.5
5.5
5.5
5.5
5.4
5.4
5.4
5.4
5.4
5.4
5.4
5.3
5.3
5.3
5.3
5.1
5.0
4.6
0.9

1998 Fine Fescue Cultivar Trial
Nick. E. Christians and Rodney A. St. John
This was the fifth and final year of data from the 1998 Finelcaf Fescue National Turfgrass Evaluation Program (NTEP) trial. It was
replaced with a new trial in the fall of 2003. It is being conducted at many locations around the U.S. The purpose of the trial is to study
the regional adaptation of 79 fineleaf fescue selections. Cultivars are evaluated for quality each month of the growing season, May
through October. The study is conducted in full sun. The plot size for each cultivar was 3 x 5 ft (15ft2). The plots, established in
October 1998, were randomly arranged and replicated three times. The trial has been maintained at a 2-inch mowing height, fertilized
with 3.5 lbs N/1000 ft" during the growing season, and irrigated when needed to prevent drought. Preemergent herbicide was applied
once in the spring of each year.
The visual quality was evaluated monthly in 2003 from May through July (Table 1). The values listed under each month in Table 1 are
the averages of visual quality ratings made on three replicated plots. Visual quality was based on a scale of 9 to 1 :9 = best quality, 6 =
lowest acceptable quality, and 1 = worst quality. The yearly average of the monthly data for each cultivar was calculated and is listed in
the last column (Mean). The first cultivar listed in Table 1 had the highest average visual quality rating for the entire 2003 season. The
cultivars are listed in descending order by average quality. The last row states the LSD (least significant difference), which is a statistical
measurement of how widely the datum in each column must vary before they are considered to be different from one another. Spring
green up data were taken in April 2002 and were estimated using a 9 to 1 scale with 9 = green and 1 = dormant turf.
Table 1. The 2003 visual quality and other turf attribute ratings for cultivars in the 1998 Fineleaf Fescue Cultivar Trial.

Fine Fescue Cultivar
ABT-HF1
LSI IT 12
SRX 3961
ABT-HF-2
ASC 172
ASC 087
AUF 008
AUF 009
ASR 049
Attila E
Minotaur
Intrigue
DGSC 94
Ambassador
Oxford
Pathfinder
Defiant
Shademark
Pick FF A-97
Jasper II
Salsa
4001
Pick Frc 4-92
BAR HF8FUS
Bridgeport
PST-EFL
Pick Frc A-93
Shademaster 1)
Discovery
Treazure (E)
PST-4HM
PST-4MB
Bighorn
ISI Frr5
ISI Frr 7
Longfellow II
ISI Fl 11
Quatro
Reliant II
ABT-HF-4
ABT-CHW-1

Species
h a rd
h a rd
h a rd
h a rd
stro n g creep in g
stro n g creep in g
h a rd
h a rd
sle n d e r creep in g
h a rd
h a rd x b lue
chew ings
stro n g creep in g

h a rd
stro n g creep in g
h a rd
stro n g creep in g
stro n g creeping
h a rd
chew ings
h a rd
chew ings
stro n g creeping
chew ings
stro n g creeping
h a rd
chew ings
chew ings
b lu e h a rd
h a rd
stro n g creep in g
stro n g creep in g
chew ings
h a rd
sh eep
h a rd
h a rd
chew ings

Greenup
5
5
5
4
5
6
4
5

5
5
5
5
5
5
5
6
6
5
4
5
6
5
6
4
5
5
4
6
4
6
5
4
5
6
5
5
5
4
5
5
5

18

May
7
6
5
6
6
7
5
5
5
5
6
5
6
6
5
7
6
7
6
7
6
5
6
6
6
6
6
6
5
6
6
6
6
7
7
6
5
5
5
6
6

•Visual Quality
Jtin
July
7
7
7
7
8
7
7
7
6
5
6
6
7
7
6
6
5
6
7
6
6
6
6
6
6
5
6
6
7
7
6
5
6
6
5
5
7
7
5
6
7
6
7
7
6
5
7
7
5
5
6
6
6
5
6
5
7
6
7
6
6
7
6
6
6
6
5
5
6
5
6
6
6
6
6
6
7
6
7
6
6
6

Mean
7
7
7
7
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6

Fine Fescue Cultivar
ABT-CHW-2
SRX 52961
SRX 52LAV
SR 5100
SR 3200
Osprey
ABT-CHW-3
ABT-CR-2
ABT-HF-3
Nordic (E)
ABT-CR-3
MB-82
ACF 083
ACF 092
ASC 082
Dawson E+
Scaldis
Brittany
Rescue 911
Magic
BAR CHF 8 FUS2
BAR CF 8 FUSI
BAR SCF 8 FU S3
PST-4FR
FST-47TCR
Florentine
Shadow II
Tiffany
MB-63
Jamestown II
Seabreeze
Cuionibra
SR 6000
Sandpiper
Heron
Banner III
Common creeping red
Boreal
LSD

Species
che w ings
stro n g creep in g
stro n g creep in g
che w ings
b lue
h a rd
chew ings
stro n g creep in g
h a rd
h a rd
stro n g creeping
h a rd
chew ings
chew ings
stro n g creeping
sle n d e r creep in g
h a rd
chew ings
h a rd
chew ings
chew ings
stro n g creeping
sle n d e r creep in g
stro n g creeping
stro n g creeping
stro n g creeping
chew ings
chew ings
chew ings
chew ings
sle n d e r creeping
chew ings
tu fte d h a ir g ra ss
chew ings
h a rd
chew ings
stro n g creep in g
stro n g creeping

Greenup
5
6
5
4
5
4
5
5
5
4
6
4
5
5
6
5
4

6
4
6
5
6
4
5
5
5
5
5
5
6
5
5
5

6
5
6
5
5
1.2

19

May

5
7

6
6
6
6
5
6
6
5
7
5
6
5
6
4
5
5
4
6
5
6
4
5
6
6
5
5
6
5
5
5
5
6
5
6
5

5
1.4

------- Visual Quality---Jun
July
6
5
5
5
6
5
5
6
5
6
6
6
6
6
6
6
6
7
6
6
6
6
6
6
5
4
5
5
5
5
5
6
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
6
5
6
5
5
5
6
5
5
5
5
6
4
5
5
5
5
5
5
5
5
6
5
5
1.0
1.1

Mean

6
6

6
6
6
6
6

6
6

6
6
6
5
5
5
5
5
5

5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
1.8

1998 Fairway Height Bentgrass Cultivar Trial
N.E. Christians and Rodney St. John
This is the fifth and final year of data from the fairway height bentgrass cultivar trial established in the fall of 1998. it was terminated
after data collection in July 2003, and a new trial was established in the fall of 2003. The area was maintained at a 0.5 inch mowing
height. This is a National Turfgrass Evaluation (NTEP) trial and is being conducted at several research stations in the U.S. It contains 26
of the newest seeded cultivars and a number of experimentáis. The cultiváis are maintained with 4 lbs of N/1000 ft2/growing season.
Fungicides are used as needed in a preventative program. Herbicides and insecticides are also applied as needed.
The visual quality was evaluated monthly in 2003 from May through July (Table 1). The values listed under each month in Table 1 arc
the averages of visual quality ratings made on three replicated plots. Visual quality was based on a scale of 9 to 1 : 9 - best quality. 6 =
lowest acceptable quality, and 1 = worst quality. The yearly average of the monthly data for each cultivar was calculated and is listed in
the last column (Mean). The first cultivar listed in Table 1 had the highest average visual quality rating for the entire 2003 season. The
cultivars arc listed in descending order by average quality. The last row states the LSD (least significant difference), which is a statistical
measurement of how widely the datum in each column must vary before they are considered to be different from one another.
Data for genetic color (Gen Color) and leaf texture (Leaf Tex) were also collected in June 2003. Genetic color was rated using a 9 to 1
scale w ith 9 = dark and 1 = light green. Leaf texture was assessed with a 9 to 1 scale with 9 = fine and 1 = coarse texture. Spring
greenup (Greenup) data were taken in April 2002 and were estimated using a 9 to 1 scale with 9 = green and 1 = dormant turf. This trial
was replaced with a new' fairway height bentgrass trial in the fall of 2003.
There was serious winter damage to creeping bentgrass cultivars in Iowa in the spring of 2003. The greenup and May data are the best
indication of which cultivars survived the winter w'ell and which ones were most severely damaged. Most plots had recovered by June
and July. The winter damage had a major effect on the mean quality ratings for this year.
Table 1. 2003 visual quality and other ratings for the Fairway Height Bentgrass Cultivar Trial.
.....................Visual Quality--------Species

Gen Color

Greenup

Leaf Tex

July

colonial

7

6

6

8

7

Penncross

creeping

6

5
3

May
7

Jun

PST-9HG

6

5

7

7

7

Princeville
ABT-Col-2

creeping

6

4

6

5

6

7

6

colonial

7

4

creeping

7

6

6
7

5
5

7

Seaside

7
5

6
6

Tiger

creeping

6

5

6

7

6

colonial

7

5

7

6

5
5

7

SRX 7MOBB

7

6

SR 7100

colonial

6

6

6

5

7

6

Golfstar

Idaho

6

5

6

6
6

5

PST-9PM

colonial

6

5
4

6

5

5

6
7

6
6

6

5

6

7

6

3
2

6

3

5

6

6
7

4

5

6

5
5

3

5

7

3

5
5

6

3
2

6

5

7
6

3
5

6

Bentgrass Cultivar

Penneagle

creeping

7

Grand Prix

creeping

6

T rueline

creeping

6
6
6

6

Mean

L-93

creeping

Century
Imperial

creeping

IS1 At-5

colonial

6
6

SRC 7MODD

colonial

7

5
4

Providence

creeping

6

4

6

5
4

5
4
5

SRX 1BPAA

creeping

7

7

4

5

7

5

SR 1119

creeping

6

3
2

6

4

5

PST-OVN

creeping

6

2

6

6

5
5

6

3
4

6
6

5

6

5

3

6
4

6

5
4

creeping

3

Seaside II

creeping

6

4

Penn G-6
Backspin

creeping

6

3

6

creeping

6

3

creeping

6

3
2

6

SRX 1120

6

3

NS

1.4

NS

1.7

LSI)

20

5

5
1.1

6
5

5

6

5
5

6

5

5
6
1.2

4
2.5

1998 Green Height Bentgrass Cultivar Trial
N.E. Christians and RA. St. John
This is the fifth and final year of data from the green height bentgrass trial established in the fall of 1998. The study was terminated
following the July data and a new green height trial was established in the fall of 2003. The area is maintained at a 3/16-inch mowing
height. This is a National Turfgrass Evaluation Program (NTEP) trial and is being conducted at several research stations in the U.S. It
contains 29 seeded cultiváis, including a number of experimentáis. Most of the plots are creeping bentgrass, but two, Pick MVB and
Bavaria, are velvet bentgrasses.
The cultivars arc maintained with a fertilizer program of 1/4 lb N applied at 14-day intervals with a total of 4 lbs of N/1000 ft2/growing
season. Fungicides are used as needed in a preventative program. Herbicides and insecticides are applied as needed.
The visual quality was evaluated monthly in 2003 from May through July (Table I ). The values listed under each month in Table 1 are
the averages of visual quality ratings made on three replicated plots. Visual quality was based on a scale of 9 to 1: 9 = best quality. 6 =
lowest acceptable quality, and 1 - worst quality. The yearly average of the monthly data for each cultivar was calculated and is listed in
the last column (Mean). The first cultivar listed in Table 1 had the highest average visual quality rating for the entire 2003 season. The
cultivars are listed in descending order by average quality. The last row states the LSD (least significant difference), which is a statistical
measurement of how widely the datum in each column must vary before they are considered to be different from one another.
Data for spring greenup (Greenup) was collected in April 2003, and data for leaf texture (Leaf Tex) and genetic color (Gen Color) were
collected in June 2003. Spring greenup data were estimated using a 9 to 1 scale with 9 - green and 1 = dormant turf. Leaf texture was
assessed with a 9 to 1 scale with 9 - fine and 1 - coarse texture. Genetic color was rated using a 9 to 1 scale with 9 = dark and I = light
green.
There was considerable winter damage on some cultivars in the spring of 2003. This damage is reflected best in the greenup data and in
the May rating. Most varieties had recovered by June and July.

Bentgrass Cultivar
Penncross
L-93
Pick CB 13-94
Pennlinks
Bavaria
Crenshaw
ISI Ap-5
BAR CB 8DS3
BAR AS 8FDS2
Pick MVB
Syn 96-2
SR 1119
SRX 1NJH
PST-A2E
Penn G-6
Penn G-l
Penn A-4
Penn A-l
Penn A-2
Backspin
Century
Imperial
Syn 96-1
Syn 96-3
SRX IBP AA
SRX 1120
Providence
SR 7200
ABT-CRB-1
LSD

Gen Color

7
7
7
7
7
7
6
6
6
7
7
7
6
6
7
7
6
6
7
6
6
6
6
6
7
6
7
7
6
NS

Greenup
5
3
3
4
3
4
3
3
3
3
2
3
2
2
2
2
2
2
2
2
2
2
2
2
2
2
3
3
2
1.3

Texture

May

7
6
7
7
6
7
6
6
7
7
7
6
7
6
6
6
7
7
7
6
7
6
6
7
7
6
6
7
7
NS

6
4
4
5
4
4
4
4
5
4
4
4
3
4
3
3
3
3
3
3
3
3
3
3
3
3
3
4
2
1.5

21

— Visual Quality—
June
July

7
6
6
6
6
5
5
5
5
5
5
5
6
5
5
5
5
6
5
4
4
5
5
5
5
5
5
4
4
NS

7
7
7
7
6
7
6
6
6
5
6
6
6
6
6
6
6
6
5
5
5
5
5
5
5
5
5
5
4
1.7

Mean

7
6
6
6
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
4
4
4
4
4
4
4
4
4
3
3.1

■

1999 Non-irrigated Fairway Height Kentucky Bluegrass Cultivar Trial
Nick Christians and Luke Dant
The fairway height Kentucky bluegrass trial was established in September 1999 to evaluate a number of the new ‘low mow' bluegrasscs
at a mowing height of 0.5 to 0.75 inches under non-irrigated conditions. The area receives 3 lbs. N/1000 ft "/year and is treated with
preemergence herbicides in the spring and broadlcaf weed controls in the fall. No fungicides arc used on the area. Dry conditions
through most of the season eliminated differences among the eultivars during 2003. April and May data are the best indication of how
the eultivars performed in the spring.
The visual quality was evaluated monthly in 2003 from April through October (Table 1). The values listed under each month in Table 1
are the averages of visual quality ratings made on three replicated plots. Visual quality was based on a scale of 9 to 1 :9 = best quality. 6
= lowest acceptable quality, and 1 = worst quality. The yearly average of the monthly data for each cultivar was calculated and is listed
in the last column (Mean). The first cultivar listed in Table 1 had the highest average visual quality rating for the entire 2003 season.
The eultivars are listed in descending order by average quality. The last row' states the LSD (least significant difference), which is a
statistical measurement of how w idely the datum in each column must vary before they are considered to be different from one another.
Table 1. 2003 Visual quality for eultivars in the Non-irrigated Fairway Height Kentucky Bluegrass Cultivar Trial

-Visual QualityMean

Apr

May

Jun

July

Aug

Oct

Nublue

6

6

5

7

2

3

5

Absolute

4

6

5

5

2

2

4

Award

4

7

5

7

3

2

4

Bluechip

4

5

4

6

2

3

4

Bluemoon

5

6

4

5

2

Ken blue

5

5

4

5

2

Liniosine

4

4

4

5

Kentucky Bluegrass Cultivar

3

4

7

4

3

3

4
4

Midnight

4

7

5

7

3

7

Nuglade

3

6

4

6

3

3

4

Park

3

4

4

5

2

4

4

Rambo

5

6

4

5

2

2

4

Rugby 11
Sodgrower 11 Mix 1

3
5

6

6

2

2

6

4
4

6

2

3

Sure-Shot13

4

6

5

6

2

2

4

Total Eclipse

3

6

5

7

2

3

4

NS

NS

NS

NS

NS

NS

NS

ISO

0.05

’ Includes Bluechip, Nustar, Rambo, and Rugby II
1’includes Nuglade, Bluemoon, Award. Rugby II, and Rambo

22

4
4

Shade Adaptation Study
ickE. Christians and
N

Luke

The shade adaptation study was established in the fall of 1987 to evaluate the performance of 35 species and cultivars of grasses. The
species include chewings fescue (C.F.), creeping red fescue (C.R.F.), hard fescue (H.F.), tall fescue (T.F.), Kentucky bluegrass (KBG).
and rough bluegrass ( P o a t r i v i a l is).
The trials are located under the canopy of a mature stand of Siberian elm trees ( U lm u s p u m i l a ) at the Iowa State University Horticulture
Research Station north of Ames, Iowa. Grasses are mowed at a 2-inch height and receive 2 lb N/lOOOfr/year. No weed control has been
required on the area, but the grass has been irrigated during extended droughts.
The visual quality was evaluated monthly in 2003 from May through October (Table 1). The values listed under each month in Table 1
arc the averages of visual quality ratings made on three replicated plots. Visual quality was based on a scale of 9 to 1: 9 = best quality, 6
= lowest acceptable quality, and 1 = worst quality. The yearly average of the monthly data for each cultivar was calculated and is listed
in the last column (Mean). The first cultivar listed in Table 1 had the highest average visual quality rating for the entire 2003 season.
The cultivars are listed in descending order by average quality. The last row states the LSD (least significant difference), which is a
statistical measurement of how widely the datum in each column must vary before they are considered to be different from one another.
Table 1 . 2003 Visual quality data for cultivars in the 1987 Shade Trial in descending order for mean quality.
Cultivar
Ensylva
Victor
Atlanta
BAR Fo 81-225
Jamestown
Biljart
Penn lawn
Banner
Shadow
Agram
Mary
ST-2 (SR 3000)
Waldina
Waldorf
Reliant
Highlight
Koket
Wintergreen
Estica
Rebel
Rebel 11
Spartan
Sealdis
Arid
Bonanza
Falcon
Coventry
Chateau
Midnight
Apache
Nassau
Bristol
Ram I
Glade
Sabre

Species1
(C.R.F.)
(C.F.)
(C.F.)
(H.F)
(C.F.)
(H.F)
(C.R.F.)
(C.F.)
(C.F.)
(C.F.)
(C.F.)
(H.F)
(H.F)
(C.F.)
(ILF)
(C.F.)
(C.F.)
(C.F.)
(C.R.F.)
(T.F)
(T.F)
(H.F)
(H.F)
(T.F)
(T.F)
(T.F)
(K.B)
(K.B)
(K.B)
(T.F)
(K.B)
(K.B)
(K.B)
(K.B)
(Poa
trivialis)

................................................... Visual Quality..........................................
May
June
July
Aug
Sept
Oct
Mean
6
6
6
6
7
6
8
7
7
7
7
7
7
6
7
7
6
7
7
7
6
4
7
7
7
8
8
7
6
6
6
6
6
7
6
5
7
6
7
6
7
6
5
6
6
6
6
6
5
6
6
6
6
6
6
6
6
6
8
6
6
5
6
7
6
6
6
7
6
6
7
6
6
7
6
6
6
5
6
7
8
6
7
6
5
6
7
7
6
6
6
6
7
6
6
6
7
6
4
7
6
5
6
7
6
4
4
4
5
5
5
5
5
5
5
5
5
6
5
5
6
5
5
4
5
5
5
6
5
6
5
5
6
4
4
5
5
5
4
5
5
4
4
3
5
5
5
5
3
5
6
6
4
5
5
4
4
4
3
5
5
3
4
4
4
5
3
3
4
4
4
4
4
4
3
3
4
4
4
4
3
5
9
2
3
2
2
3
3
9
2
2
2
3
4
3
2
4
3
3
3
3
3
4
3
4
3
2
4
3
2
2
2
2
3
2
2
2

2

2

2

2

2

2

2

2

1

2

3

2

3

2

2

2

2

4
3

2

2

2

2

2

2

2

2

1.4
1.4
1.5
1.6
1 .6
2 .8
1.3
ESI) o.o5
'C.F. = chewings fescue, C.R.F. = creeping red fescue, H.F. = hard fescue, K.B. = Kentucky bluegrass, T.F. = tall fescue

23

O rnam ental G rasses Project 2000-2002
Nick Christians

Purpose:
The purpose of the ornamental grass project is to evaluate 34 ornamental grasses for their adaptation to Iowa conditions. The study is
located south of the lurfgrass research building. Grasses 1 and 2 were established in 1989. Grasses 3-5. 11-15, 17-18. 20-21, and 33
were established in 2000. The remaining grasses were established in June of 2001.
Each plot on this site has a 4 x 5 ft spacing. The grasses are located on the south side of the maintenance building at the Turf Research
Farm. The grasses descend in height from number one in the center, to 34 on each of the ends. The 34 grasses are replicated twice on the
two sides of the arc (Figure 1). The grasses are either cut down or burnt down each spring.
Choosing the species:
Ornamental grasses have numerous characteristics, each that could make a difference in which species is chosen for a particular
landscape. For the plots at the Horticulture Research Station, the new species have general characteristics of being bunch type, nonaggressive, varying in color, form and shape, in addition to being able to grow in zones 4 and/or 5.
The grasses will remain in this location for several years. They will be evaluated on their winter survival and overall adaptation to local
conditions.
Figure 1. Plot map and layout of the Ornamental Grasses Project.

Table 1. Species, common name and expected growing height of the 34 grasses used in the Ornamental Grasses Project.
1
2
3
4
5

6
7

8
9

10
11
12
13
14
15
16
17
18
19

20
21
22
23
24
25
26
27
28
29
30
31
32
33
34

Genus Species
Miscanthus floridulus ‘Giganteus’
Miscanthus sinensis
Miscanthus sinensis “Strictus*
Panicum virgatum “Cloud Nine'
Miscanthus sinensis “Graziella'
Miscanthus sinensis “Silberfeder
Molina caerulea ssp. arundinacea ‘Transparent'
Molina caerulea ssp. arundinacea “Skyracer
Molina caerulea ssp. arundinacea ‘Windspiel'
Molina litorialis “Fontaene'
Calamagrostis x acutiflora ‘Karl Foerster’
Miscanthus sinensis ‘Variegatus'
Miscanthus sinensis ‘Silberspinne'
Panicum virgatum ‘Prairie Sky’
Panicum virgatum ‘Heavy Metal’
Panicum virgatum
Miscanthus sinensis Purpurascens'
Sorghastrum nutans
Andropogon gerardii
Calamagrostis arundinacea ‘Brachyticha'
Panicum virgatum “Haense Heims’
Panicum virgatum ‘Shenandoah*
Panicum virgatum “Rotstrahlbusch’
Spodiopogon sibirieus
Bouteloua curtipendula
Molina caerulea ‘Karl Foester'
Schizaehyrium seoparium “The Blues’
Deschampsia cespitosa ‘Bronzeschleier'
Deschampsia cespitosa ‘Goldstaub'
Helictotrichon sempervirens ‘SaphireSprudel'
Festuca mairei
Molina litoralis “Bergfreud'
Festuca glauca “Superba'
Festuca glauca ‘JEhjalGBlue^^

Common Name
Giant Chinese Silver Grass
Japanese Silver Grass
Porcupine Grass
Switch Grass
Japanese Silver Grass
Silver Feather
Tall Moor Grass
Tall Moor Grass
Tall Moor Grass
Tall Moor Grass
Feather Reed Grass
Japanese Silver Grass
Japanese Silver Grass
Switch Grass
Switch Grass
Switch Grass
Japanese Silver Grass
Indian Grass
Big bluestem
Korean Feather Reed Grass
Red Switch Grass
Red Switch Grass
Red Switch Grass
Siberian graybeard
Side-oats grama
Variegated Purple Moor Grass
Little bluestem
Tufted Hair Grass
Tufted Hair Grass
Blue-oat Grass
Atlas Mountain Fescue
Tall Moor Grass
Blue Fescue
Blue Fescue

24

Expected Growing Hem ht
12-15*
8’
8'
8’
5-6’
6-8’
5-7'
7-8’
6-7'
6'
4-5'
8’
4-5’
6’
3-4’
5’
3-4’
3-5’
5’
3'
4’
4'
5’
4’
3’
6-7'
2-3’
3’
2-3’
2-3’
2-2.5'
5-6’
1-2'
8”

2003 Crabgrass Control Trial
Luke Demt and Nick E. Christians
Introduction
The purpose of this study was to evaluate the efficacy of several preemergence and postemergence herbicides for control of crabgrass.
The study was conducted at the Iowa State University Research Facility on ‘Park’ Kentucky bluegrass. To ensure uniformity, the plot
area was seeded with crabgrass in early April 2003.
Material and Methods
The trial was arranged as a randomized complete block in which each treatment was replicated three times. Each plot measured five feet
by five feet. Treatments 2 through 10 were screened for Syngenta, 11-15 for Dow Agrosciences, 16-22 for The Scotts Company and
treatments 23 and 24 were products of The Andersons Company.
All liquid treatments were applied using a carbon dioxide backpack sprayer with #8002 flat fan TecJct nozzles at 30-40 psi and diluted to
a total spray volume of 3 gal per 1000 sq. ft. Granular materials were applied using ‘shaker dispensers’ in order to provide uniform
application. The initial prccmergencc application took place on April 28, 2003. On June 5. the 1-3 leaf stage application was made. The
4-6 leaf stage application took place on July 1 I. Treatments 11 and 14 required that an application be made 6-8 weeks AIT (after initial
treatment). This 6-8 week AIT reapplication took place on July 2, 2003.
Turf quality was taken on May 27, 2003, on a scale of 1-9, with I being the worst, 6 being acceptable and 9 being excellent. On August
7. 2003, the number of crabgrass plants in each plot were recorded. Percent crabgrass cover data was taken on August 28, 2003. This
percentage is reported as the percentage of the plot covered by crabgrass (0% = No crabgrass present and 100% being entirely covered
with crabgrass).
Data were analyzed using Statistical Analysis System and the Analysis of Variance procedure. Treatments effects were tested using the
Least Significant Difference (LSD) test.
Results
None of the products damaged the turf. The higher quality ratings on some plots w'ere due to the presence of fertilizer in these products.
Mesotrione is an experimental product from Syngenta that provides some postemergence control of crabgrass in Kentucky bluegrass. In
our study, this product was combined with the preemergence material. Barricade 4FL. The most effective application timings of these
two materials was a postemergence application at the 1 to 3 leaf stage of crabgrass, followed by an additional application at the 4 to 6 leaf
stage (treatments 8 and 9; Table 1). Treatment 10, which included an application of Barricade at the 1 to 3 leaf stage followed by
Barricade and Mesotrione at the 4 to 6 leaf stage, was also highly effective.
Dimension Ultra 40 WP and Dimension 2 EW were most effective when applied before crabgrass germination at the 0.5 lb ai/A rate.
The 0.25 lb ai/A rates, applied both before crabgrass germination and again 6 to 8 weeks later were not as effective.
Of the dry commercial products tested for the Scott’s company, all provided significant reductions in crabgrass cover with the exception
of Miraclc-Gro Lawai Fertilizer and Bayer Advanced.
The Anderson’s Dimension product was effective at controlling crabgrass at the 0.25 lb ai/A rate, but not at the 0.15 lb ai/A rate.

25

Table 1.

Turf quality, the number of crabgrass plants per plot and percentage cover of crabgrass for the 2003 Iowa State University crabgrass control
trial. Percent Crabgrass Cover is reported as the percentage of the plot covered by crabgrass (0% = No crabgrass present and 100% being entirely
_______ covered with crabgrass)._______ _________________________________________________

Trt.

1
2
3
4
5
6
7

Material
Untreated Control
Barricade 4 FL*
Barricade 4 FL*
Mesotrione
Barricade 4 FL*
Barricade 4 FL*
Mesotrione
Barricade 4 FL*
Mesotrione
Barricade 4 FL*
Mesotrione
Barricade 4 FL*
Mesotrione

Application
Timing
N/A
Preemergence
Preemergence
1-3 leaf stage
1-3 leaf stage
1-3 leaf stage
1-3 leaf stage
1-3 leaf stage

Turf Quality

Number of Crabgrass
Plants per Plot

Percent Crabgrass
Cover

May 27

Aug 7

Aug 28

4.7
5.3

73
23

26
7

5.0

6

7

Rate
lb a.iJA
N/A
0.65
0.65
0.187
0.65
0.65
0.0624
0.65
0.125
0.65
0.187
0.65
0.125

8
Barricade 4 FL*
Mesotrione
Barricade 4 FL*
Mesotrione

4-6 leaf stage
1-3 leaf stage

73

33

45

11

5.7

39

11

5.3

23

11

5.3

4

1

5.7

1

0

5.3

7

t

0.65
0.125
0.65
0.187

9
Barricade 4 FL*
Mesotrione
Barricade 4 FL*

5.3
5.3

1-3 leaf stage

0.65
0.187
0.65

Barricade 4 FL*
Mesotrione

4-6 leaf stage

0.65
0.25

11

Dimension Ultra 40 WP
Dimension Ultra 40 WP

Preemergence
6-8 weeks AIT

0.25
0.25

5.7

15

12

12

Dimension Ultra 40 WP

Preemergence

0.5

5.0

1

0

13

Barricade 65 WG

Preemergence

0.5

5.3

13

8

14

Dimension 2 EW
Dimension 2 EW

Preemergence

6-8 weeks AIT

0.25
0.25

5.3

78

38

Dimension 2 EW

Preemergence

0.5

5.3

33

4

Scotts Turf Builder with
HALTS
Sta-Green Premium
Crab-Ex

Preemergence

1.5

7.0

20

6

0.252

8.0

19

3

0.252

8.0

19

3

1.5

8.0

35

13

0.39

7.3

60

27

3.03

6.3

9

8

4.0

7.7

3

0

0.15

6.3

47

23

0.25

6.3

6

3

33.78

17.89

10

15
16
17
18

Vigoro Ultra Turf

19

Miracle-Gro Law n
Fertilizer

20

Bayer Advanced

21

Pree’n Green Lawns

22

S-10833

4-6 leaf stage

Preemergence
Preemergence
Preemergence
Preemergence
Preemergence
Preemergence

23

Anderson's Dimension

Preemergence

24

Anderson's Dimension

Preemergence

LSD 0.05
0.96
* Denotes that X-77 non-ionic surfactant was used at a rate of 0.25 percent volume by volume

26

Selective Removal o f Creeping Bentgrass from K entucky Bluegrass
Marcus A. Jones and Nick E. Christians
Introduction:
Creeping bentgrass often encroaches into collars, roughs, and other golf course sites where it is unwanted. Invasion frequently occurs
during the seeding process, but can also result from improper mowing, affecting both new and established golf courses. This is becoming
an increasing problem as the number of courses utilizing creeping bentgrass fairways continues to rise.
The goal of this study is to determine if any herbicides have the capability of selectively removing creeping bentgrass from Kentucky
bluegrass. Our three objectives are to:
1. Determine the best time of application that provides for selective postemergence control of creeping bentgrass in Kentucky
bluegrass.
2. Determine the rate of application for selective postemergence control of creeping bentgrass in Kentucky bluegrass, and
3. Observe any detrimental effects to the Kentucky bluegrass from the herbicide applications.

Research Progress
Field Research - A field trial was started during the fall of 2003. The research is being conducted at Coldwater Golf Links in Ames, 1A
on the Kentucky bluegrass/creeping bentgrass rough established on native soil. The research plots arc maintained at a height of one inch
and contain a mix of L-93 creeping bentgrass and Sure Shot Kentucky bluegrass. Sure Shot is a Kentucky bluegrass blend containing
Nuglade. Bluemoon, Award, Rugby II. and Rambo cultivars. The field trial is examining the efficacy of MON 44951, a sulfonylurea
produced by Monsanto containing the active ingredient sulfosulfuron. MON 44951 has been shown to effectively control rough
bluegrass, yellow nutsedge, tall fescue and quackgrass. Additional field testing on other grassy weeds needs to be completed before the
product will be released for commercial sales.
The randomized complete block trial was replicated three times and received weekly applications of MON 44951. applied with a
surfactant, starting August 29, 2003, and concluding October 25, 2003 (Table 1). MON 44951 was applied at two rates: 0.25 oz/A and
0.50 oz/A. A list of the treatments can be found in Table 1 below. Weekly phytotoxicity data w>as recorded on a scale of 9-1
(9=Exeellent, 6=Least Acceptable, l=Worst). Grid counts were performed the second week in November to determine the percent cover
of each turfgrass species and were also performed the following spring. The research is ongoing and the results will be available in
future Iowa Turfgrass Research Reports.
Table 1. MON 44951 Fall 2003 treatments
Application Dates
4th week
Aug.

1st week
Sept.

2nd week
Sept.

3rd week
Sept.

4th week
Sept.

1st week
Oct

2nd week
O ct

3rd week
Oct.

4th week
Oct.

Treatments

1

Control

2

MON 44951 75 DF at 0.25 oz/A plus MON 0818 at 0.25% v/v

3

MON 44951 75 DF at 0.50 oz/A plus MON 0818 at 0.25% v/v

Greenhouse Research - A second experiment was conducted the following w inter (December 23, 2003 - March 1, 2004) in the
greenhouse with mesotrione (Callisto) in addition to MON 44951. Mesotrione, a callistemone, is marketed by Syngenta and is used to
control broadleaf and grass weeds in grain crops. Four-inch diameter plugs of L-93 creeping bentgrass and Sure Shot Kentucky
bluegrass were grown in six-inch pots with native soil and were maintained at a height of one inch beneath high-pressure sodium lamps
providing 16-hour photoperiods.
The experiment was a completely randomized design with 26 treatments and five replications (Table 2). Data was recorded for quality,
stress, amount of regrowth, and herbicidal effects on rooting. Quality data was recorded weekly on a scale of 9-1 (9=Excellent, 6=Least
Acceptable, l=Worst). Stress data was also analyzed weekly by using a Walz Mini-Pam fluorometer. A fluorometer measures
photosynthetic yield based upon the amount of light given off at longer wavelengths. Less fluorescence means more light is being
utilized for photosynthesis equaling healthier plants. Regrowth was measured approximately every 10 days by cutting all samples to one
inch and collecting the clippings. Clippings were dried at 68°C for 72 hours before being weighed. Rooting effects (Figure 1) w'ere
measured at the end of the experiment by washing and ashing the roots in a muffle furnace. Fisher’s LSD (a=0.05) w^as used to separate
means.

27

Greenhouse Results:
MON 44051 applied at 1.0, 1.25, and 1.5 oz/A effectively controlled creeping bentgrass. However, these rates were equally as harmful to
Kentucky bluegrass (Table 2). Similarly, the same rates negatively affected the rooting of both creeping bentgrass and Kentucky
bluegrass (Figure 1). Overall, mesotrione failed to provide adequate control of creeping bentgrass. Plans for future work include
additional field studies in the fall of 2004 as well as further work in the greenhouse the following winter, 2004-2005.
Table 2. Visual quality of creeping bentgrass (Agrostis stolonifera L.) and Kentucky bluegrass (Poa pratensis L.) treated with 13

different rates of mesotrione and MON 44951 over time. Values are means of five treatments.______ _____ __
Fime(weeks)
6
7

2

3

4

5

Kentucky bluegrass
Creeping bentgrass

9.0
7.6

9.0

9.0
7.8

9.0

Mesotrione/0.125
Kentucky bluegrass
Creeping bentgrass

9.0

9.0

6.8

8.2

9.0
7.8

9.0
7.6

9.0
9.0

Mesotrione/0.37
Kentucky bluegrass
Creeping bentgrass

9.0

Mesotrione/0.5
Kentucky bluegrass
Creeping bentgrass

9.0

Mesotrione/0.625
Kentucky bluegrass
Creeping bentgrass

Chemical/Rate A.I./A)

8

9

10

Mean

7.4

8.5
7.6

Species
Control
9.0
7.2

7.8
6.8

8.2
8

8.2
8

9.0
4.6

8.8
5.4

6.8
5.6

8.4
7.2

8.4
7.6

8.4
7.2

9.0
5.4

9.0
5.2

6.4
5.6

8.6

8.2

7.4

8.3

7.4

7.2

6.8

6.8

9.0
8.4

9,0
7.0

8.8

8.8

8.8
8.6

8.6

8.8

7.0

7.8
7.2

9.0

6.4

8.2

7.8

7.7

9.0
7.0

9.0
5.6

9.0
6.4

9.0
6.4

7.0
7.2

7.8

8.0

8.0

8.2

8.4

7.2
7.8

8.3
7.2

9.0

9.0

8.2

9.0
4.8

8.8

8.0

5.0

9.0
6.4

7.0
6.2

8.4
7.8

8.4
7.6

Mesotrione/0.75
Kentucky bluegrass
Creeping bentgrass

9.0
7.0

9.0
4.4

9.0
4.0

9.0
3.6

9.0
5.8

7.0
6.8

8.2
8.2

8.4

8.0

8.5

8.6

7.8

6.2

MON 44951/0.25
Kentucky bluegrass
Creeping bentgrass

9.0
7.6

9.0
8.4

9.0
7.2

9.0
7.2

8.8
6.6

4.6
6.4

4.4
7.8

4.0
7.6

4.4

8.0

6.9
7.4

MON 44951/0.5
Kentucky bluegrass
Creeping bentgrass

9.0
7.4

9.0

9.0
7.0

8.8

8.8

6.4

8.2
5.8

4.6
4.6

4.2
5.0

4.0
4.8

3.8
4.8

6.1

MON 44951/0.75
Kentucky bluegrass
Creeping bentgrass

9.0
8.4

9.0

9.0

5.0

4.2
4.2

4.2
4.4

4.0
4.0

3.8
4.0

6.8

6.8

9.0
5.6

8.6

8.6

MON 44951/1.0
Kentucky bluegrass
Creeping bentgrass

9.0
7.6

9.0

8.8
6.8

4.4

8.2
4.0

4.4
3.6

4.4
3.6

4.0
3.2

3.6
3.2

6.7
5.0

MON 44951/1.25
Kentucky bluegrass
Creeping bentgrass

9.0
7.8

9.0

8.8
6.8

5.2

7.6
4.0

3.8
3.6

3.8
3.6

3.2
3.4

3.0
3.4

6.3
5.2

MON 44951/1.5
Kentucky bluegrass
Creeping bentgrass
LSI) 0.05

9.0
7.8
0.7

9.0
8.4

8.0
4.0

4.8
3.6
1.2

4.6
3.4

4.0
3.4
0.9

3.4
3.6

6.7
5.1

Mesotrione/0.25
Kentucky bluegrass
Creeping bentgrass

8.6

8.8

8.6

8.6

1.0

6

8.6

8.6

9.0

8.8

6.2
1.1

5.2
13

28

1.1

1.2

8
8.0

8.5

7.6

6.8

8.2

8.5

7.4

6.8

1.0

6.7

5.7

7

IK B

DCB

dL ddL
tn

o
O

MON 44951

Mesot rione

T reatinents

Figure 1. Root weights of Kentucky bluegrass and creeping bentgrass as determined by ashing after treatment effects.

29

Evaluation of plant growth enhancer (GABA - gamma am inobutyrie acid) for Establishm ent of
A g r o s tis p a lu s tr is Huds.
I). D . M i n n e r a n d S .K . L e e

See web site for picture version
ht tp://\v ww.hort.iastatc.eclu/i acuity stniT/meet<aciiItv7miiiner/turirpt/2004

Introduction
Gamma aminobutyrie acid (GABA) is a plant growth enhancer based on a non-protein amino acid. It enhances nutrient uptake by roots
and leaves so that plant nutrient levels arc higher than those achieved by using nutrients alone. When plants are stressed and nutrient
uptake is limiting, it is believed that this product facilitates nutrient utilization, thereby enhancing growth during stress.
This study was conducted to evaluate the efficacy of GABA for establishment of Creeping bentgrass

(A g ro s tis p a lu s tr is

Huds.)

Materials and Methods
This study was conducted for 10 weeks at the Iowa State University Horticulture Research Station in Ames. Iowa. The trial was
conducted using a randomized complete block design. Each treatment was replicated three times with plots being 5*5 ft. Creeping
bentgrass was seeded to plots at July 30, 2003. Plots received 0.3 inches of water per day for 30 days. Watering occurred every hour for
10 minutes, six times per day, for 30 days. As the seedlings matured, turf was watered less frequently but never allowing wilt. Treatment
description appears in Table 1. Treatment 1 was an untreated control. Treatment 2 was treated only one time as a soil drench right after
seeding. Treatments 3-7 were applied weekly for 6 weeks after 50% of the plot area was showing germinated seedlings.
Table 1. List of treatments____________________ _____________ __________________ _________________ ___________
Treatment #____________________________________________ Treatment list_________________________________________
TRT 1
Control - No treatment
TRT 2
300 ppm GABA applied as soil drench right after seeding
TRT 3
150 ppm GABA applied to the seedling emerged & weekly for 6 weeks after emergence
TRT 4
300 ppm GABA applied to the seedling emerged & weekly for 6 weeks after emergence
TRT 5
Foliar fertilizer with 150 ppm GABA applied to the seedling emerged & weekly for 6 weeks after emergence
TRT 6
Foliar fertilizer with 300 ppm GABA applied to the seedling emerged & weekly for 6 weeks after emergence
_____ TRT 7_______ Foliar fertilizer only weekly for 6 weeks after emergence_______________________________________________

Observations began two weeks after germination. Turf color and percent turf cover were visually rated. Turf height was measured every
3 weeks. Grass clippings were taken from two cores per each plot at the end of the study. The clippings were oven-dried at a temperature
of 67 °C for 24 h and weighed. At the end of the study, rooting depth was also evaluated from two cores per each plot. Visual
observation was used for rooting depth.
Data were subjected to analysis of variance by using the Analysis of Variance (ANOVA) procedure, and mean separation was performed
by the least significant difference (LSD) method with the Statistical Analysis System (SAS).
Results and Discussion
On August 20, 2003, (two and three weeks after treatment application of Trt 3 and Til 2), plots treated by GABA with fertilizer (Trt 5
and 6) produced 7-35% more turf coverage than plots treated by GABA without fertilizer (Trt. 3 and 4) (Fig. I ) This trend seemed to
increase with time. Plots treated by GABA with fertilizer created 27-63% more turf coverage than plots treated by GABA without
fertilizer on Oct. 10 (8 and 9 weeks after TRT 3 and TRT 2 were started). However, no differences were found between GABA rates
within treatments with fertilizer or without fertilizer. Turf coverage was affected by fertilizer but was not influenced by the addition of
GABA.
There was a significant difference in turf color that was observed on three of the four observations dates (Fig. 2 ). Once again there was
an increase in turf color as a result of fertilizer, but no color enhancement from GABA addition.
Turf height was significantly different on two of the four measurement dates (Fig. 3 ). On the final observation date, GABA+fcrtilizer
(TRT 5 and 6 ) produced taller grass than fertilizer applied alone. However, this increase in height did not cause an increase in the
clipping dry weight sampled at the termination of the study (Fig. 4)
Visual observation was used to measure rooting depth Trts 5 to 7 created more roots than Trts l to 4. No differences were found between
GABA rates with fertilizer and between GABA rates without fertilizer.

30

Date

Turf color
(1 to 9, 9= best color)

Fig. 1. Percent turf cover o f A g r o s tis p a lu s tr is Huds. by gamma aminobutyric acid (GABA) and foliar fertilizer. Values are
means of three replicates. Vertical bars represent the least significant difference (LSD) at p-value 0.05 probability level. The
LSD is not significant if the ‘NS’ is indicated instead of vertical bar and significant if the vertical bar is followed with LSD value.

Date
Fig. 2. Mean turf color (visual evaluation 1 to 9. *6' is the lowest acceptable value. Larger numbers mean better color) per unit
surface area of A g r o s tis p a lu s tr is Huds. by gamma aminobutyric acid (GABA) and foliar fertilizer. Values are means of three
replicates. Vertical bars represent the least significant difference (LSD) at p-value 0.05 probability level. The LSD is not
significant if the ‘NS' is indicated instead of vertical bar and significant if the vertical bar is followed with LSD value.

31

3.00
2.50
gT 2.00

§

a>

1.50

sz
H—

L.

H 1-00
0.50
0.00

8/22

8/27

9/1

9/6

9/11

9/16

9/21

9/26

10/1

10/6

Date

C lip p in g d ry w e ig h t ( g m -2 )

Fig. 3. Mean turf height (cm) per unit surface area o f A g r o s tis p a lu s th s Huds. by gamma aminobutyric aeid (GABA) and foliar
fertilizer. Values are means of three replicates. Vertical bars represent the least significant difference (LSD) at p-value 0.05
probability level. The LSD is not significant if the VNS' is indicated instead of vertical bar and significant if the vertical bar is
followed with LSD value.

Treatment

Fig. 4 . Mean clipping dry weight (g*m"2) of A g r o s tis p a lu s tr is Huds. by gamma aminobutyric acid (GABA) and foliar fertilizer.
Values are means of three replicates. Vertical bars represent the least significant difference (LSD) at p-value 0.05 probability
level. The LSD is not significant if the ‘NS’ is indicated instead of vertical bar and significant if the vertical bar is followed with
LSD value.

32

Evaluation of plant growth enhancer (GABA - gamma am inobutyric acid) for
siL. growth and sod establishm ent
praten
D . D . M i n n e r a n d S .K . L e e

Introduction
Gamma aminobutyric acid (GABA) is a plant growth enhancer based on the non-protein amino acid. It enhances nutrients uptake
by roots and leaves so that plant nutrient levels are higher than can be achieved with nutrients alone. When plants arc stressed
and nutrient uptake is limiting it is believed that this product facilitates nutrient utilization, thereby enhancing growth during
stress.
Materials and Methods
This study was conducted for ten weeks at the Iowa State University Horticulture Research Station in Ames. Iowa, and for four
weeks in a greenhouse at Iowa State University. The trial was conducted using a randomized complete block design. Each
treatment was replicated three times with plots being 5*4 ft. Treatments were applied on July 30. 2003 to a mature stand
‘Unique’ Kentucky bluegrass {P o a p r a te n s is L.) growing on a 6-inch pad of sand. Treatment 1 was an untreated control.
Treatments 2 and 3 were 150ppm and 300ppm GABA with foliar fertilizer, respectively. Treatment 4 was only foliar fertilizer.
Treatments were applied weekly for 6 consecutive weeks. Fifty passes per week were applied with the modified Brouwer Traffic
Simulator during each week during week 5 and 6. Two cores per plot were harvested after 6 weeks of treatment and transplanted
in the greenhouse to evaluate recovery.

Table 1. List of treatments
Treatment #
TRT 1
TR I 2
TRT 3
TRT 4

Treatment list
Control - No treatment
150 ppm GABA with foliar fertilizer
300 ppm GABA with foliar fertilizer
Only foliar fertilizer

Turf color and quality were evaluated visually every ten days during a 50 day period. (Visual ratings followed a 1-9 scale, where
1 is the worst and 6 is the lowest acceptable rating) Grass w'as mowed at a height of 1.5 inches every 5 days and clippings were
collected every 10-days. During the recovery phase in the greenhouse, one of the two subsamples from each treatment received
two additional applications of its respective GABA and/or foliar fertilizer treatment. Two weeks after this application, turf
color, quality, and clipping dry weight were measured again. Finally, to determine if there was any effect from the GABA on
recovery after traffic or prior to w ilt stress all grass samples underwent a two w'cck period without irrigation.
Data were processed using the analysis of variance (ANOVA), and mean separation w>as performed by the least significant
difference (LSD) method with the Statistical Analysis System (SAS).
Results and Discussion
No difference was found for turf color, quality and clipping dry weight during the 6 week field trial in the summer 2003 (Table.
2).
A visual increase in turf height was observed when samples were treated and allowed to recover in the greenhouse after
application of field traffic. The 300ppm GABA with foliar fertilizer produced higher shoot growth after traffic stress. However,
there was no significant difference on clipping dry weight after traffic stress (Table 2). There were no significant differences
among greenhouse samples that did not receive treatments to recover from the traffic period.
There were no differences among treatments when wilting stress was applied.
Table 2. Summary of ANOVA to evaluate AuxiGro products for Kentucky bluegrass growth.
Source of
variance

df

T reatment

3

Source of
variance

df

Treatment

3

Turf* quality

Turf Color
8.9

8.19

8.29

9.8

9.18

8.9

8.19

8.29

9.8

9.18

NS

NS

NS

NS

NS

NS

NS

NS

NS

NS

Clipping dry weight
before traffic stress
8.9

8.19

8.29

9.8

9.18

NS

NS

NS

NS

NS

NS : Not significant

33

Clipping dry weight
two weeks after traffic stress
. , . ,
No additional
Additional treatment
treatment
NS
NS

2003 Postem ergence Annual Bluegrass Trial
N i c k E. C h r i s t ia n s a n d L u k e D a n t

This study was conducted to assess the efficacy of Velocity herbicide for annual bluegrass control applied at differing intervals to
fairway height creeping bentgrass. The trial was conducted at Veenker Memorial golf course on ‘Cato’ creeping bentgrass.
The trial was arranged in a randomized complete block format. Each treatment was replicated three times and plots were five
feet by five feet. Treatments were applied using a carbon dioxide backpack sprayer with #8002 Hat fan TeeJet nozzles at 30-40
psi and diluted to a total spray volume of 3 gal per 1000 sq. ft The initial application was made on July 18 with sequential
treatments made as listed in Table 2.
Turfgrass quality was taken on the dates specified in Table 2 to evaluate any phytotoxic effects that may have occurred. A scale
of 1-9 with 1 being the worst, 6 being acceptable and 9 being excellent was used to access turfgrass quality. There was initial
phytotoxicity from the treatments, but they recovered later in the season.
The P o a a n n u a population was reduced during the winter and the population in the control was only 4 % on May 6 when data
were collected (Table 1). There was no significant reduction of P o a an n u a in response to the treatments.

Table 1. Treatments and P oa a n n u a percent in the Velocity study.

Tit
1
2
3
4
5

Material

Untreated Control
Velocity 80WP
Velocity 80WP
Velocity 80WP
Velocity 80WP

Rate

Rate

g a.i./A

ih a A./A

N/A
30
30
30
30

N/A
0.066
0.066
0.066
0.066

LSD

Application
Interval

Percent

P o a an n u a

(d a y s )

5/06/04

N/A
7
14
21
28

4.0
6.7
6.3
5.3
2.0
NS

34

Table 2. Turfgrass quality following the application of Velocity herbicide to fairway height creeping bentgrass.

Trt

Material

1

Untreated
Control
Velocity
80 WP
Velocity
80WP
Velocity
80 WP
Velocity
80 WP

2

3
4
5

Rate
g
a.i./A

Rate
lb
a.i/A

N/A

N/A

30

0.066

30

0.066

30

0.066

30

0.066

Application
Interval

T u rfg ra s s Q u a lity

7/25/03

8/01/03

8/08/03

8/15/03

8/22/03

8//29/03

9/05/03

9/15/03

8.00

8.00

8.00

8.00

8.00

8.00

8.00

8.00

6.00

5.67

7.00

8.00

8.00

8.00

8.00

8.00

6.00

7.00

6.00

7.33

7.33

7.67

8.00

8.00

6.00

7.00

8.00

5.00

7.67

8.00

8.00

8.00

6.00

7.00

8.00

8.00

5.33

7.00

7.67

8.00

0.1

0.49

0.1

0.49

0.69

NS

NS

NS

N/A
7 days
14 days

21 days
28 days

LSD

Table 3. The date of second application for each treatment.
Trt

Second Application Date

1

N/A

2

7/25/03

3

8/01/01

4

8/08/03

5

8/15/03

Table 4. Weather conditions as reported in Ames, Iowa on each application date.
Application Date
7/18/03

7/25/03

8/01/03

8/08/03

8/15/03

Temperature (°F)
(at time o f application)

72

80

67

70

68

High Temperature(°F)

83

93

71

86

92

I)ew point (°F)

70

64.1

67

65

68

Wind speed (mph)

0-5

0-10

0-5

3-6

calm

Humidity

94%

58%

87%

84%

100%

35

Timing o f Roundup® Application Critical when C onverting G olf Course G reens and
Fairways to Roundup® Ready C reeping Bentgrass
Luke Dont, N.E. Christians, and Shui-ZJiang Fei
Roundup Ready* creeping bentgrass {A g r o stis sto lo n ife r a L.) (RRCB) may provide a management tool to prevent P o a ann u a
infestation in putting greens and fairways. Unfortunately, the complete renovation to RRCB would be costly and render a golf
course unplayable for a significant period of time. If it was possible to incorporate the interseeding of RRCB into regular
maintenance processes such as verticutting and aerification, existing greens and fairways could slowly be converted to RRCB.
The objective of this study was to observe the effects of Roundup'6' timing before and after interseeding to determine the impact
of competition from conventional grasses on the establishment of RRCB.
Materials and Methods
Site

The study was conducted at Vecnker Memorial Golf Course in Ames, Iowa on one green and three fairways built on modified
native soil. The research putting green was ‘Penncross' creeping bentgrass, and the fairways were Timeline' creeping bentgrass,
Double Eagle Kentucky bluegrass mix, and Scotts 100-81600 perennial ryegrass mix. The green was maintained at a height of
0.145 inches and the fairways were mown at 0.60 inches.
Procedure

Treatment 1 was the control in which a bare soil seedbed was prepared. Treatments 2-11 were core aerified in two directions
using 5/8 inch tines. The aerification cores on the putting green study were removed and the area was topdressed to fill the
aerification holes. The aerification cores on the fairway were broken up using a vertical mower and thearea wasdragged.
RRCB seed w'as applied to both the green study and the fairway study and the plotswere lightly vcrticut and spiked to ensure
seed-to-soil contact. All areas were seeded on September 3, 2002, at a rate of 1.75 lb per 1000 square feet. The seed used
contained 50% RRCB with the remaining 50% being conventional creeping bentgrass.
Roundup5 was applied at a rate of 2 quarts per acre to treatments 1-10. For treatment 11, a rate of 0.5 quarts per acre was used
for each application. Roundup0 was applied at a rate of 2 quarts per acre to the entire area on May 7. 2003, to determine the
actual population of RRCB.
Treatments
1. Apply Roundup0' 14 days prior to seeding, remove sod and prepare seedbed, apply Roundup® 28 days after seeding to
remove Roundup ' susceptible seedlings.
2.

Apply Roundup® 7 days prior to seeding and 28 days after seeding.

3.

Apply Roundup® at time of seeding and 28 days after seeding.

4.

Apply Roundup® 7 days after seeding.

5.

Apply Roundup® 7 days after seeding and 28 days after seeding.

6.

Apply Roundup® 14 days after seeding.

7.

Apply Roundup® 14 days after seeding and 28 days after seeding.

8.

Apply Roundup® 28 days after seeding.

9.

Apply Roundup® at one-fourth of the recommended rate at seedling emergence; apply three repeated applications at
one-fourth of the recommended rate at two-week intervals (to suppress and gradually remove the existing grass).

10. Apply Roundup® at the end of the 2002 growing season.
11. No Roundup® application until the spring of 2003.
Results and Discussion
Competition from existing turfgrass significantly reduced the t imeliness of establishment. Roundup applications made 7 days
before seeding, at seeding, or 7 to 14 days after seeding were most effective at removing competition of existing conventional
grasses and speeding complete RRCB establishment (Table 1).

36

The conversion of fairways to RRCB was very effective; however, the renovation of the creeping bentgrass putting green to
RRCB using these methods proved to be less successful (Table 1). Consequently, more research is being done to improve the
timeliness of conversion to RRCB on putting greens.
Table 1. Percentage-cover on June 1,2003, of Roundup Ready ' " creeping bentgrass on areas previously established to creeping
bentgrass maintained at green height and creeping bentgrass. Kentucky bluegrass. and perennial ryegrass maintained at
fairway height. Each area was intraseeded with Roundup Ready® creeping bentgrass on September 3, 2002. Values are
means of observations from three replications.

Percentage cover of Roundup Ready® creeping bentgrass

Roundup® application timing
Bare Soil3*
7 days before seeding2
At time of seeding7
7 days after seeding
7 days after seeding7
14 days after seeding
14 days after seeding7
28 days after seeding
rate in 4 applications
End of growing season
Spring of 2003
V

a

Green height
Creeping
bentgrass

Creeping
bentgrass

Fairway height
Kentucky
bluegrass

Perennial
ryegrass

84

96

97

100

75*
60*

99

100
100

99
98

90

49*

87

95

95

55*
44*

85

98

90*

70
84*

85

94

40*

86

90*

32*

72 *

92

42*

84

77*
98

20 *
4*

67*

67*

82*

7*

6*

30*

97

7 These treatments also received an application of Roundup*' 28 days after seeding.
y Existing turf was removed and seed was sown into soil.
* Values within each column are significantly different from the control at P < 0.05 according to Dunnetf s one-tailed t-test
against the control.

37

Benefits Evaluation of

P o a a n n u a Control in Roundup Ready® Creeping Bentgrass
Luke Danî, N.E. Christians, and Shui-Zluing Fei

Introduction
Roundup Ready '9 creeping bentgrass (RRCB) was recently developed by The Scotts Company and Monsanto and is expected to
be commercially available in late 2004. The greatest advantage of this transgenic grass is that it may finally be possible to
eliminate P o a a n n u a in golf course putting greens and fairways, a task that has proven to be virtually impossible up until this
point. The benefits of RRCB seem to be blatant, but remain unknown. The purpose of this study is to compare and quantify the
maintenance inputs, performance and overall turf quality of a monostand of RRCB to mixed stands of RRCB and P o a a n n u a
maintained at putting green height.
The hypothesis of this study is that the maintenance and performance of a monostand of RRCB is the same as the maintenance
and performance of mixed stands of RRCB and P o a a n n u a .
Materials and Methods
E xperim ental Design

In the fall of 2003, a native soil putting green was established at the Iowa State University Turfgrass Research facility consisting
of the following treatments:
•
•
•
•

100% RRCB
85% RRCB / 15%
50% RRCB / 50%
20% RRCB / 80%

P o a annua
P o a annua
P o a annua

Each treatment is replicated three times with plots being 10 feet by 14 feet. These plots will be further divided into a control
treatment and Primo ( tr in e .x a p a c - e th y l) treatment. The area will be maintained at a height of 5/32 of an inch and receive uniform
irrigation and fertilizer applications.
Data collection
O v e r a l l T u r f Q u a lity

Turf quality will be assessed on a weekly basis on a scale of 1-9 with 9 being excellent, 1 being worst, and 6 being lowest
acceptable.
D is e a s e in c id e n c e

Disease incidence will be recorded upon the presence of the disease, The percentage of the plot affected will be reported as will
the pathogen present and the species on which the damage occurred, After documentation, the plot will be treated with an
appropriate fungicide to control the pathogen.
W ilt

During July 2004, the area will be monitored for signs of wilt on a daily basis. This will be recorded as a percentage of the plot
affected.
B a ll R o ll

Stimpmeter readings will be conducted once per week. One reading will be made shortly after mowing and another will be taken
that same day alter 4 p.m.
M a in te n a n c e I n p u ts

At the conclusion of the 2004 season, herbicide and fungicide inputs will be summed up for each plot and presented on a volume
basis, and the amount of active ingredient per acre and an estimated dollar amount will be calculated.
Current Status
Data collection will begin in late May to early June of 2004. The study will continue through the summer of 2005 and the results
will be presented in the 2005 field day report.

38

Techniques for C onversion of C onventional Putting Greens to Roundup Ready® Creeping
Bentgrass
Luke Dank N.E. Christians, and Shui-Zhang Fei
In 2002, a Roundup Ready® creeping bentgrass (RRCB) putting green and fairway conversion trial was established at Veenker
Memorial Golf Course, in this trial, aerification and vertical mowing were used to create openings in the soil for seed placement
From the results of the 2002 trial, it was apparent that aerification and vertical mowing were not effective for converting putting
greens to RRCB. The objective of this new putting green conversion trial is to research methods, which allow putting greens to
be converted to RRCB in a timely manner.
This trial
•
•
•

is designed to determine the effects on conversion to RRCB when:
Four mechanical methods are used,
Three seeding rates are used with each mechanical method, or
Three seeding dates with each mechanical method.

Materials and Methods
Site and E xperim ental Design

This trial is being conducted at the Iowa State Turfgrass Research Facility on a native soil putting green established to
‘Penncross' creeping bentgrass. It is divided in two areas, one-area to investigate seeding rate within each mechanical treatment,
and the other to investigate seeding date within each mechanical treatment. The trial is a split-plot design in which the whole plot
is a mechanical treatment and the sub-plots represent seeding rates (Figure 1) or seeding dates (Figure 2).

Figure 2. E x p e r im e n ta l d e s ig n

Figure 1. E x p e r im e n ta l d e s ig n
o f s e e d in g r a te s tu d y

o f s e e d in g d a te s tu d y

0.5

8/19

1.5

1
Mechanical
Device

2.5

9/09

1

1
Mechanical
Device

Seeding Rate
lb RRCB/WOO sq. ft

1
/ \

__ /

9/30

Seeding Date
\ ___ 2003

Treatments
> Bare Soil Seedbed
> Aerification / Vertical Mowing
• 5/8 inch tines-2 directions
> Vertical Mowing using Toro triplex-2 directions
>
TIP Green Spiker
• Apply mechanical treatment, sow Vi of seed, apply mechanical treatment in opposite direction, sow remaining
seed, apply mechanical treatment
> Terra Combi Spiker
• Apply mechanical treatment, sow' Vi of seed, apply mechanical treatment in opposite direction, sow' remaining
seed, apply mechanical treatment
> Graden Vertical Mower
> Vertical blades at one-inch spacing-2 directions
Procedure
S e e d in g R a te S tu d y

On August 18, 2003, one day prior to seeding, all plots were treated with Roundup® at a rate of 1.5 quarts per acre. On August
19, all mechanical treatments were applied to the whole plot and seeding was sown at the rates of 0.5, 1.5 and 2.5 lb RRCB per
1000 square feet on the sub-plots. Each plot was lopdrcsscd w'ith sand to smooth the surface and fill in any voids created by the
mechanical treatment. A 19-25-5 starter fertilizer was applied at 1 lb N per 1000 square feet following topdressing. The entire

39

area was treated with Roundup0' at 1 quart per acre 21 days after seeding. This was done to remove any creeping bentgrass that
was not tolerant of Roundup as the seed used was 60% RRCB and 40% conventional creeping bentgrass.
S e e d in g D a te S tu d y

One day before the seeding dates of August 19, September 9. and September 30, Roundup09 was applied at 1.5 quarts per acre to
each plot. Each mechanical treatment was applied to individual sub-plots on the designated seeding dates. All plots were seeded
at a rate of 1.5 lb RRCB per 1000 square feet and were topdressed with sand to fill in voids and smooth the surface. Following
topdressing, a 19-25-5 starter fertilizer was applied at 1 lb N per 1000 square feet. Each plot was treated with Roundup 21 days
alter seeding at 1 quart per acre to remove any bentgrass that was not Roundup® tolerant.
Data Collection

Data collection began in the fall of 2003 and will continue through the summer of 2004. Percentage cover of RRCB and
turfgrass quality (on a scale of 1-9, 9 = best, 6 = lowest acceptable, and 1 = worst turf quality ) will be used to determine the
success of each treatment. Also, the date when each plot is acceptable for play will be recorded in order to calculate “days from
seeding to opening for play/'

Preliminary Results
Seeding Date Study

The earliest seeding date, August 19, achieved the greatest coverage on all dales data was collected except for April 21.2004
(Table 1). There were no significant differences between the mechanical methods used in the conversion process (Table 2).
Seeding Rate Study

On September 3, 2003, the 2.5 lb rate had the greatest cover and the 1.5 lb rate w>as greater than the 0.5 lb rate. By September 22,
the coverage of the 2.5 lb rate was no longer greater than the 1.5 rate, but the 0.5 lb rate had significantly less RRCB cover than
both of the higher rates. This trend continued until April 21, 2004 (Table 3).
The Terra Combi Spiker and bare soil methods had greater RRCB cover than the aerification/vcrtical mowing treatment on
September 3, 2003. On September 22, 2003, every method but the Graden had greater RRCB coverage than the
aerification/vertical mowing treatment. Approximately two w^eeks later, only the Terra Combi Spiker and bare soil treatments
had significantly more cover of RRCB than aerification/vertical mowing methods. On all other dates in which data was
collected, there were no statistically significant differences between the methods used in the conversion process (Table 4).

Discussion
M echanical M ethod

From the preliminary results, it appears that the conversion process is quickest when the mechanical method used creates many
smaller soil openings for seed placement (i.e. Terri Combi Spiker. TIP spiker) rather than fewer, larger soil openings (i.e.
aeri fi cation/v ert ica 1mo wi ng).
Seeding Date

it is fairly apparent that the greatest RRCB coverage is achieved when seeding takes place earlier in the fall. An earlier seeding
date does not guarantee a successful conversion to RRCB. However, it does make establishment less dependent on ideal weather
conditions later in the fall.
Seeding Rate

The results of this study seem to indicate that there is no advantage to seeding at a rate of 2.5 lb when compared to 1.5 lb. RRCB
per 1000 square feet. The rate of 0.5 lb appears to be inferior to the higher seeding rates.

40

Table 1. Percentage cover of RRCB averaged across the 5 mechanical methods for each seeding date.
Percent RRCB Cover

Seeding
Date

22-Sep-03

07-Oct-03

28-Oct-03

06-Apr-04

13-Nov-03

21-Apr-04

19 Aug

91.3 az

94.3 a

97.9 a

99.0 a

98.6 a

99.2 a

09 Sept

22.0 b

48.1 b

78.6 b

82.9 b

87.9 b

92.7 a

47.7 c

44.0 c

37.3 c

58.0 b

30 Sept

...

...

Table 2. Percentage cover of RRCB averaged across the 3 seeding dates of August 19, September 9 and September, 30 for each
mechanical method.
Percent RRCB Cover
------------------------------------------------------------------------07-Oct-03
28-Oct-03
13-Nov-03
22-Scp-03

Mechanical Method

06-Apr-04

21-Apr-04

Bare Soil

57.5 a

74.7 a

74.0 a

76.2 a

75.3 a

80.0 a

Acrification/Vcrticutting

50.8 a

61.7 a

67.6 a

68.1 a

70.7 a

81.1 a

Graden Vertical Mower

53.3 a

69.0 a

76.7 a

77.9 a

78.8 a

88.9 a

TIP Spiker

59.7 a

75.2 a

77.2 a

75.6 a

74.2 a

83.9 a

Terra Combi Spiker

61.8 a

75.5 a

78.1 a

78.7 a

74.1 a

82.7 a

06-Apr~04

21 -Apr-04

Table 3. Percentage cover of RRCB averaged across all 5 mechanical methods for each seeding rate.
Seeding
Kate
lb /1000 sq f t

Percent RRCB Cover
3-Scp-03

22-Sep-03

28-Oct-03

07-Oct-03

13-No v-03

0.5

39.3 a

83.0 a

88.5 a

97.1 a

96.4 a

96.7 a

97.8 a

1.5

73.3 b

96.5 b

97.8 b

99.2 b

99.4 b

99.3 b

99.9 b

2.5

87.1 c

97.5 b

98.9 b

99.9 b

100.0 b

99.6 b

100.0 b

Table 4. Percentage cover of RRCB averaged across the 3 seeding rales loi cacn mecnamcai mcinoci.
Percent RRCB Cover
Mechanical Method
3-Scp-03

22-Sep-03

07-Oct-03

28-Oct-03

13-Nov-03

06-Apr-04

21-Apr-04

Bare Soil

79.2 a

97.1 a

98.3 a

98.8 a

98.4 a

98.2 a

99.6 a

Aerification/Verticutting

49.4 b

86.1 b

90.3 b

98.0 a

97.2 a

97.2 a

98.4 a

Graden Vertical Mower

62.8 ab

90.9 ab

94.2 ab

99.0 a

99.0 a

99.3 a

99.3 a

TIP Spiker

68.7ab

92.6 a

94.4 ab

98.0 a

98.8 a

98.2 a

99.0 a

Terra Combi Spiker

72.8 a

95.1 a

98.1 a

99.8 a

99.8 a

99.6 a

99.8 a

z Values within columns with the same letter are not significantly different at the Tukey’s multiple comparison error rate of P

41

<

0.05

Field Perform ance o f Roundup Ready C reeping Bentgrass
S f in i- z h a n g F e i a n d R o d n e y S t. J o h n

One of the major challenges for creeping bentgrass management is the control of annual blucgrass and other grassy weeds, most of which
cannot be readily controlled by conventional weed control programs due to their similar response to herbicides. Herbicide-tolerant crops,
particularly crop species tolerant to the non-sclective herbicide Roundup1 (active ingredient glyphosate), gained acceptance in some
countries and were grown extensively during the past decade in the United States. The development of Rounduplytolerant creeping
bentgrass would offer great promise for the golf industry because it would provide simplified and a more effective control of aggressive
annual and perennial weeds including annual bluegrass, roughstalk blucgrass, bermudagrass and many other grassy and broadleaf weeds
in golf course turf. Roundup Ready creeping bentgrass is currently being considered by USDA for possible deregulation. Once
deregulated. Roundup Ready creeping bentgrass could soon become available. The objective of this study is to compare field
performance of the Roundup Ready creeping bentgrass with a number of conventional creeping bentgrass cultivars including Crenshaw,
L 93, Penncross. Pcnncaglc. Penn A4 and Providence under fairway conditions.
Materials and Methods
The trial was established Fall 2002 at Iowa State University Turf Research Facility. The experiment is a completely randomized design
with three replications. All entries were maintained under the same fairway conditions with a mowing height of 0.5 cm, 4 lbs of N/I000
ftVgrowing season. Fungicides are used as needed in a preventive program. Herbicide treatments are listed in Table 1.
Results
G round coverage

Percentage of ground cover was recorded from March through June when the Roundup Ready plots were almost completely covered
(Table 2). In March, all plots have only a small percentage of ground coverage. By June, the coverage has increased greatly, particularly
the Roundup Ready genotypes with a Roundup application in early May. However, the percentage of ground cover for Roundup Ready
creeping bentgrass was within the ranges observed for conventional creeping bentgrass.
T u rf grass quality

From July to October, turfgrass quality for each plot was recorded (Table 3). The quality of Roundup Ready creeping bentgrass was
within the ranges that were observed for conventional creeping bentgrass.

Table 1. A list of treatments for both conventional cultivars and Roundup Ready Creeping bentgrass
Treatment
Cultivar
Roundup 21 DAE* Roundup late fall Weed control as needed
1
2

L 93

No

Penncross

3

Penneagle

4
5

No, CWC**

CWC

No

No, CWC

CWC

No

No, CWC

CWC

Providence

No

No, CWC

CWC

Penn A-4

No

No, CWC

CWC

6

Crenshaw

No

No, CWC

CWC

7

Roundup Ready A

Yes, 48 oz/A

No, CWC

CWC

8

Roundup Ready A

Yes, 48 oz/A

Yes, 48 oz/A

Roundup.48 oz/A

9

Roundup Ready B

Yes, 48 oz/A

Yes. 48 oz/A

Roundup,48 oz/A

10

Roundup Ready A + B

Yes, 48 oz/A

Yes. 48 oz/A

Roundup.48 oz/A

*DAE: Days after emergence; **CWC: Conventional weed control;

42

Tabic 2. Ground coverage of both conventional cultivars and Roundup Ready Creeping bentgrass

Percent Ground Coverage«
Entry
L 93
Penncross
Penneagle
Providence
Penn A-4
Crenshaw
Roundup Ready
Roundup Ready
Roundup Ready
Roundup Ready
LSD 0.05

A
A
B
A+B

March

April

May

June

23.3

40.0

45.0

63.3

33.3
28.3
26.7

51.7
35.0

61.7
41.7

35.0

50.0

83.3
73.3
65.0

18.3
11.7

35.0
21.7

46.7
45.0

66.7
61.7

8.3

23.3
25.0

78.3
83.3
81.7
91.7
25.7

15.0

33.3
30.0

48.3
53.3
53.3
60.0

15.4

15.8

17.7

11.7
10.0

Table 3. Tuifgrass quality for conventional cultivars and Roundup Ready Creeping bentgrass

Turf Quality
Entry

July

L 93
Penncross
Penneagle
Providence
Penn A-4
Crenshaw
Roundup Ready A
Roundup Ready A
Roundup Ready B
Roundup Ready A + B
LSD 0.05

6.7
6.3
6.3
6.0

6.7
5.7

August September October Average
6.3
6.7
6.7
6.3
6.3

6.0

6.0

6.3

6.0

6.3

6.3

5.7
5.0

6.0

6.2

6.0

5.8

5.0

6.0

6.0

7.3

5.7

6.0

6.2

6.7
6.7
6.7

6.7
6.7
7.0

6.7

6.0

6.0

6.0

6.7

6.3

6.5
6.3
6.7

6.3

6.3

6.0

6.3

6.3

0.9

1.2

0.8

0.8

0.7

43

Identification and characterization o f CBF gene in perennial ryegrass

p e r e n n e L)

Y a n w e n X i o n g a n d S h u i- z h a n g F e i

Introduction
Perennial ryegrass (L oliu m p e re n n e L.) is an important turf and forage grass used extensively throughout the temperate regions in the
U.S. The primary breeding goal of perennial ryegrass is to improve its tolerance to abiotic stress conditions, particularly winter hardiness.
Winter hardiness is the ability for plants to tolerate a wide range of winter environmental stresses including low temperatures, rapidly
fluctuating temperatures, low light intensity, desiccation, wind, snow, ice cover, and disease. Freezing tolerance is an important
component of winter hardiness in plants. It has been reported to be highly correlated with field winter survival in many plants including
perennial ryegrass {L oliu m p e re n n e L). Freezing tolerance of plants is controlled by multiple genes, each of which contributes a small
effect. Identifying these quantitative genes is difficult because their effects on the plant phenotype are often influenced by the
environment. Because of these shortcomings, using conventional breeding to improve abiotic stress tolerance has met with limited
success.
In the model plant A r a h id o p s is , a class of regulatory genes, CBF / DREB (C-repeat Binding Factors / Dehydration Response Element
Binding factor) activate stress responses. Such regulatory genes can serve as “master switches“ that activate a signal transduction cascade
that leads to enhanced abiotic stress tolerance. Similar regulatory genes have been isolated in a number of different species. Overexpression of some of these CBF genes enhanced tolerance to freezing and dehydration. Our goal is to use the molecular approach to
improve winter hardiness in perennial ryegrass. The specific objective of this project is to use the Reverse Transcriptase - Polymerase
Chain Reaction (RT-PCR) approach to isolate and characterize CBF genes from perennial ryegrass.
Method and material
To isolate CBF genes in perennial ryegrass, we designed primers based on conserved regions of all known plant CBF genes. DNAs and
RNAs from the perennial ryegrass cultivar of “Caddieshack“ were extracted and used as a template in the following experiment. Because
CBF genes are cold inducible in other plants, we prepared RNAs from both cold treated plants and non-treated plants.
RT-RCR was performed on the RNA samples. The amplified products were then cloned and sequenced. Specific primers were then
designed for RACE (Rapid Amplification of cDNA End) to obtain the sequences on both ends of the conserved region. Genomic DNAs
were then used as templates for PCR and the amplified products were sequenced to obtain the full gene sequence. Protein sequence was
deduced from the full length cDNA sequence.
Northern hybridization was performed in roots, stems, leaves and flowers to determine the expression pattern of the isolated CBF gene
after exposing the plants to low temperatures for various times.
Results

(1) G en e Iso la tio n : A CBF gene (designated as LpCBF) was isolated using the RT-PCR and RACE methods from the perennial ryegrass
cultivar of Caddieshack. LpCBF gene has all of the conserved domains of known CBF genes from other plant species, and it has 60%
similarity to the rice CBF gene. Sequence alignment showed that more than half of the amino acids are identical between LpCBF and
CBF genes of rice.
(2) : E x p ressio n P a ttern o f L pC B F : To characterize the spatial-temporal expression pattern of the LpCBF gene. Northern blot was
performed using RNAs extracted from plant leaves treated by 4°C cold for 15 min, 30 min, 1hr. 4hr, 6hr, 9hr, 24hr and 48hr. RNAs
extracted from untreated plants were used as a control. The expression of LpCBF RNA was detected only at the 30min and lhr
treatment, with the highest level detected at 3()min. Our results showed that the expression of LpCBF was induced between 15 min and
30 min of cold treatment. The expression then reaches its highest level at 30 min of cold acclimation and lasts for at least another 30
min. No more LpCBF expression was detected after 2 hours of cold treatment, which indicated that the CBF gene isolated from perennial
ryegrass functions in early steps of the cold acclimation process. No LpCBF expression was detected in non-cold treated leaves, stems,
crowns and roots. This is similar to other known plant CBF genes. Whether LpCBF gene expression is tissue specific in cold-treated
plants will be examined.
Further studies will focus on the functional analysis of LpCBF by transferring this gene to the model plant A r a h id o p s is to determine its
function in freezing tolerance.

44

M apping of Q uantitative Trait Loci (QTL) for W inter H ardiness in Perennial Ryegrass
Yartwen

Xiong,Shui-zhangFeiand Reed Barker

Introduction
Perennial ryegrass {L o lim n p e re n n e L) is an important turf species. It has a fast establishment rate, strong seedling vigor, good tolerance
to both traffic and low mowing which makes it a good choice for use on golf course fairways and athletic fields. However, perennial
ryegrass has a poor ability to survive in the severe winter, which limits its use in the far northern areas of United States, including low'a.
One important breeding objective for perennial ryegrass is to improve its winter hardiness.
Winter hardiness is a complex quantitative trait that is controlled by multiple genes with each having minor genetic effect. In addition,
the expression of such genes is often affected by the environment, which makes it difficult to identify such genes. With the development
of DNA marker techniques, it is now possible to locate these genes (quantitative trait loci, QTLs) that are associated with winter
hardiness. There are abundant DNA marker variations present in natural population; some of these markers are in the same chromosome
as the genes responsible for winter hardiness. These markers often transmit together with the winter hardiness genes into their progenies.
The DNA markers are stable and relatively easy to identify compared to winter hardiness genes that are influenced by the environment
and difficult to identify w ith classic genetics. The long-term goal of this project is to facilitate germplasm improvement of perennial
ryegrass with enhanced winter hardiness through marker-assisted selection (MAS). The specific objectives of this research are to identify
the QTLs that are associated w ith winter hardiness in perennial ryegrass.
Materials and methods
P la n t m a te r ia ls :A segregating population of 174 genotypes was created by crossing a perennial ryegrass cultivar ‘Manhattan’ with an
annual ryegrass cultivar ‘Floregon.’ While Manhattan has good winter hardiness. ‘Florcgon’ is very sensitive to winter killing. This
population was maintained in our research greenhouse at 20-21°C and w^as fertilized with Miracle Gro to prevent nutrient deficiency.
Irrigation was provided as needed. In May 2003, four clones of each genotype were planted in the field within each replication in an a
lattice design with three replications. The distance between individual clones of a genotype is 30 cm, and the distance between each
genotype is 60 cm. The distance between rows is 90 cm.
Data collection

Plants were mowed on July 17, August 14. and September 22, respectively. Fall regrowth was measured as the vertical
height of regrowth in centimeters on November 14. Fall regrowth may be correlated with winter hardiness.
F a ll re g ro w th :

Freezing tolerance was assessed by measuring ion leakage. One clone of each genotype was removed from the field
on November 30, 2003, and was placed into a sealed plastic bag with a wet paper towel in a corner and then stored at a 4 °C in a walk-in
cold room. Individual tillers of similar size were separated from sampled plants, and were then washed quickly in deionized distilled
water to remove the soil and blotted dry in a paper towel. The aerial parts and roots w^ere trimmed to 2 cm and 0.5 cm respectively. For
each genotype. 18 individual tillers were prepared and then placed into glass tubes (16 x 125mm) with 2 tillers in each tube. Eight
different temperature treatments (-6°C, -10°C, -14°C, -18°C, -20°C, -24°C, -28°C, -32°C) were applied to every two trimmed tillers
using a ScienTemp programmable freezer (Model:8.5-3.1), and the 4°C treatment was used as a control. The freezer was first equilibrated
at -2°C, -3 °C and -4 °C for 30 minutes, respectively. The duration at each test temperature is 15 minutes. The temperature was cooled at
a rate of 2°C per hour until - 10°C when the temperature started to lower at a rate of 4°C per hour until it reached -32°C. Samples were
taken out at each test temperature and thawed on ice overnight. The conductivity of these samples w^as measured to calculate ion leakage.
The freeze-treated samples were infiltrated twice for 4 min each after adding 7ml ddH20 and shaken horizontally for 1 hour at 250 rpm.
The conductivity was then measured with an YS1 conductance meter (model 3403). Total conductivity for each sample was determined
by measuring the autoclaved samples. Percentage of ion leakage was plotted as a function of the freezing temperatures. LT 50 value was
determined from the midpoint between the maximum and minimum (control) ion leakage obtained for each genotype.
F re e zin g to le ra n c e :

W in ter s u n n v a l:

Winter survival was evaluated at the end of April using a scale of I - 5 with 1 being completely dead and 5 being no

injury.
Q T L s a n a ly sis: Data for the same characters will be measured again in 2004. Once the second-year data becomes available. QTL
analysis will be conducted. First, a single-factor Analysis of Variance (ANOVA) analysis will be computed for each pair wise
combination of quantitative traits and maker loci. The trait values of all individuals having a marker will be compared with those without
this marker by using an F test. Then the interval mapping method will be used to find the more robust position of QTL’s.

45

Analysis o f Genetic Diversity in Rough bluegrass, Colonial and Velvet Bentgrasses Using R APD
M arkers
Shanmugam

Rajasekar.S
iZhang
ltu

and Nick Christians

Introduction

Rough bluegrass (P o a tr iv ia lis ) is a cool-season perennial grass that is grown in wet shaded locations for home lawns, golf courses and
sports fields, it is also used for winter overseeding of warm season turfgrasses in south where it forms one of the highest quality turf of
any cool-season turfgrasses. Colonial bentgrass (A g ro s tis c a p illa r is ) is a sod-forming, cool-season perennial grass, primarily grown in
northeastern and northwestern regions of the United States. This fine textured grass spreads by short rhizomes and stolons to form close
tight turf and is best suited to golf course fairways. Velvet bentgrass (A g r o s tis c a n in a ), the finest textured of all bentgrasses. is adapted to
cool, moist areas of coastal regions of the United States. It is primarily used on putting greens, where it forms an attractive, low-growing,
compact turf with a high-quality putting surface. It is also the most shade-tolerant of all the bentgrasses and is used on fairways where
nitrogen levels are kept low. All of these three species are not extensively utilized, partly due to the lack of breeding efforts. Germplasm
of turfgrass species, including the aforementioned three species, are being collected by USDA plant introduction stations throughout the
world. However, these germplasm are largely uncharacterized genetically. To better utilize these collections, genetically characterizing
each accession of these species is critically important. Molecular markers are a powerful, reliable and cost effective tool for evaluating
genetic diversity and can provide important insights for breeding. The objectives of this research were to: (1) evaluate the genetic
diversity of selected accessions and varieties of rough bluegrass, colonial bentgrass and velvet bentgrass using RAPD(Randomly
Amplified Polymorphic DNA) markers, and (2) evaluate the morphological variations of these materials under field conditions.
Materials and methods
This research involves 61 accessions, including 27 accessions of rough bluegrass, 27 accessions of colonial bentgrass, and 7 accessions
of velvet bentgrass that were obtained from the Western Regional Plant Introduction Station (USDA) at Pullman. WA. All seeds were
sown in cell packs and DNA was extracted from young leaves after growing one-month in the greenhouse. After the seedlings reached a
desirable height, they were transplanted to the Iowa State Horticulture Research Farm for further studies on morphological characteristics
under field conditions. All accessions were planted in a randomized complete block design with a maximum of 18 replications for each
accession.
RAPD analysis is based on the polymerase chain reaction (PGR). After DNA extraction, PCR conditions were optimized for RAPD
primers by examining at least four accessions. Eighty primers were screened for polymorphism. Fifteen out of 80 primers that showed
high polymorphism were used to analyze the 27 accessions of rough bluegrass.
ITie PCR products were checked by agarose gel electrophoresis. The polymorphic bands w'erc scored either as ‘T ’ for presence and “0"
for absence and a similarity coefficient matrix was formed. This matrix was analyzed by the “Mesquite” software to construct
dendrogram and principal coordinate analysis. Using this similarity coefficient matrix, genetic distance was analyzed by the “PAUP *
software.
Results
Dendrogram analysis showed that accessions in three out of five clusters in the dendrogram tree have a positive relationship with their
geographic origins. This is confirmed by their genetic distances. Genetic distances showed that accessions from the United States and
Iraq have high genetic distance between them. Accessions from Denmark and Yugoslavia have low genetic distance between them. Data
on morphological characteristics of these accessions is unavailable at present.
For colonial and velvet bentgrasses, DNA was extracted and PCR was optimized. Primers were screened and 18 out of 80 primers that
were screened showed high polymorphism. Data on genetic distance and morphological characteristics of these accessions is unavailable
at present.

46

Physiological R esponses o f C reeping Bentgrass to M ow ing
Mark Howieson and Nick E. Christians
Development of practical mowing programs that balance agronomic requirements with sports play demands is important to produce
dense, uniform, and visually appealing turf. The overall objective of our current research projects is to evaluate the performance of
creeping bentgrass (Agrostis stolonifera L.) after common mowing practices. Practices of interest include mowing frequency (i.c.,
single- or double-cutting) and mower sharpness.
Grasses maintained on sports fields often are double-cut or mowed twice in different directions, to create a more uniform playing surface.
This practice is especially prevalent on golf course greens. However, the effects of multiple cuttings on the growth, development, and
physiological status of creeping bentgrass have not been identified. Primary areas of research to quantify severity of mowing stress
include carbohydrate metabolism and activities of antioxidant enzymes.
Mowing removes leaf tissue that grasses use to acquire solar energy, effectively lowering the rate of photosynthesis and limiting the
ability of the plant to synthesize carbohydrates. Re-growth and initiation of new' leaf tissue after mowing is necessary to develop the
photosynthetic leaf area required for production of carbohydrates. Grasses often increase leaf and shoot density below the height-of-cut
to reestablish leaf surface area. Plants rely on carbohydrate reserves to provide energy and raw materials required to redevelop leaf and
shoot tissue.
Mowing is a destructive process that wounds grass plants and increases the susceptibility of grass plants to other stresses. Formation of
reactive oxygen species is a typical response of plants to wounding. Accumulation of reactive oxygen species may lead to damage of
carbohydrates, lipids, proteins, and nucleic acids. Damage to these macromoleculcs may result in reductions in rates of photosynthesis
and respiration. Because of the highly toxic nature of reactive oxygen species, plants have developed enzymatic systems to scavenge
reactive oxygen species and protect cells from oxidative damage.
Regular mower maintenance is essential to achieve the best possible quality of cut. Dulled mower blades tear and fray leaf blades,
resulting in brown and ragged leaf tips that reduce the visual quality of the turf. Moreover, grasses mow n with dull mowers are subjected
to more stress than grasses mown with sharp mowers.
Several methods of sharpening reel-type mowers exist, including single-blade grinding, spin-grinding, carbide-milling, back-lapping, and
facing of the front face of the bedknife. The decision on which method, or combination of methods, to use often depends on economic,
labor, and time factors, as well as desired cutting quality and personal preference. There is no set standard regarding how often reel-type
mowers should be sharpened. That depends on several factors, such as the area of turf to be mowed, the regularity of cutting, the species
of grass being cut, the method used to sharpen the mower, and the adjustment of the reel to the bedknife.
An objective of a current research project at Cold Water Golf Links is to develop general guidelines to determine how frequently reeltype mowers should be sharpened. Mowers were sharpened by using different sharpening techniques and arc used to mow a known area
of turf each week. Measurements of leaf blade tissue damage, carbohydrate concentration, photosynthetic yield, and cutting surface
geometry are used to quantify mower sharpness over time.

Significance
Determining the re-growth potential and quantifying the stress caused by mowing practices will allow us to make general
recommendations to turfgrass managers regarding the design and implementation of mowing programs. In addition, data garnered from
the field study will provide timelines for proper mower maintenance to ensure the highest quality of cut.

47

Evaluation o f Fungicides for Control of D ollar Spot and Brown Patch in C reeping B entgrass 2003

MarkL.Gleason, SaraJ. Helland,
Trials were conducted at Veenkcr Memorial Golf Course in Ames, Iowa. Creeping bentgrass was maintained at 0.16 inch cutting height.
Fungicides selected for activity against dollar spot and brown patch were applied using a modified bicycle sprayer at 30 psi and a dilution
rate of 3 gal per 1000 sq ft. The experimental design was a randomized complete block with four replications. All plots measured 4 ft x
5 ft. Because several treatments were added to the trial after it began, spray applications were initiated on June 10 and June 24 (garlic oil
treatments). These were followed by re-applications at recommended intervals until August 20. Visual estimates of disease severity
were made at approximately 10-day intervals starting on July 17. Percent disease severity for dollar spot and a qualitative scale of 0-5 for
brown patch were used to estimate severity, where 0 = no disease; 1 = 1-5%; 2 - 6-10%; 3 = 11-25%; 4 = 26-50%; 5 = >50% plot
symptomatic. Data were analyzed using the GLM procedure in SAS, and mean separations were determined using Fisher’s protected
LSD at P<0.05.
Disease pressure was moderate to severe for dollar spot and brown patch. Most of the tested products suppressed both diseases
significantly (P<0.05) in comparison to the unsprayed check. No phytotoxicity symptoms were observed during the trial.
Table 1. Dollar spot and brown patch trial 2003. Veenkcr Memorial Golf Course, Ames IA (creeping bentgrass). Plot size: 20 ft2 (4

ft x 5 ft); 4 plots per treatment
Trt #
1

2
3
4
5

6
7

8
9

10
11
12
13
14
15

1
2
3
4
5

6

Product

Company
Check
BASF
BASF
BASF
BASF
BASF
Cleary
Cleary
Bayer
Bayer
USA Absorbents
USA Absorbents
USA Absorbents
USA Absorbents
USA Absorbents
LSI) (0.05)
Check
BASF
BASF
BASF
BASF

Rate/ 1,000 ft2

Interval
(days)
14

17.Tul
16.2
0.7

21

0.0

14
14

—
Emerald 70WG
Emerald 70WG
Insignia 20WG
Emerald 70WG ROTATE
Insignia 20WG '
Propieonazole Pro 1.3 MC
Endorse 2.5WP
Spectra 90WDG
26GT 2SC
Bayleton 50DF
Garlic Oil
Garlic Oil
Garlic Oil
Garlic Oil
Garlic Oil

0.13 oz
().18oz
0.9 oz
0.13 oz +
0.9 oz
1.0 fl oz
4 oz
4 oz
4 fl oz
0.5 oz
5% v/v
5% v/v
10% v/v
10% v/v
10% v/v

14
14
14
14
14
7
14
7
14

21

0.0

0.0

0.1

3.0

5.5

0.0

0.0

9.5
().()

13.0
0.4

0.13 oz
0.18 oz
0.9 oz
0.13 oz +
0.9 oz
1.0 fl oz
4 oz
4 oz
4 fl oz
0.5 oz
5% v/v
5% v/v
10% v/v
10% v/v
10% v/v

14

21
14
14

23 Aug
36.7

0.0
0.0
26.2

0.0

0.0

0.0

0.2

1.4

0.2

16.7

15.5

0.0
0.0
0.0

26.5
().()

50.0
().()

0.5

10.3

9.5

22.0
0.2
0.0
0.0
2.2

8.0

8.2

7.2
13.5
15.5

11.2

8.6

Emerald 70WG
Emerald 70WG
Insignia 20WG
Emerald 70WG ROTATE
Insignia 20WG
Propieonazole Pro 1.3 MC
Endorse 2.5WP
Spectra 90WDG
26GT 2SC
Bayleton 50DF
Garlic Oil
Garlic Oil
Garlic Oil
Garlic Oil
Garlic Oil

Dollar spot severity ( %) 11
27 Jul
6 Aug
15 Aug
16.2
19.2
30.7
0.7
().()
0.5

4.2
3.5

1.2
0.2
2.2

0.0
0.0
7.7
8.7
7.1
Brown
3.5

2.2
1.7

0.2
1.0

0.0
0.0
21.2
8.2

2.7
2.5
8.5

7.2
17.5
14.2
2.2
12.1
6.2
patch severity (1 -5 scale)11
4.5
2.0
0.7
0.0
0.2
2.5

2.2
1.5

0.2
0.2

0.1
0.0
5.5
9.5
2.5

10.2
1.2
10.9
4.7
1.7

0.2
1.5

0.0

BASF
14
1.2
0.2
2.7
0.5
1.5
Cleary
14
0.7
0.7
2.2
0.0
2.5
8 Cleary'
14
0.7
2.7
0.7
0.0
1.0
Bayer
14
0.2
1.2
9
0.0
0.0
1.2
14
10 Bayer
0.7
2.2
1.0
2.2
1.2
11 USA Absorbents
7
1.7
3.7
3.7
0.0
1.7
12 USA Absorbents
14
4.0
5.0
4.0
2.2
0.5
13 USA Absorbents
7
0.2
4.7
1.7
2.5
1.2
14 USA Absorbents
14
4.5
3.5
4.2
3.0
1.0
15 USA Absorbents
21
4.5
2.0
3.2
0.7
1.2
LSI) (0.05)
1.4
2.0
1.5
1.3
1.5
Product applications were rotated on a 14-day interval (Emerald June 10, July 8 and August 5; Insignia June 24, July 22 and August 19).
11Disease severity ratings on the following qualitative scale: 0 = no disease; 1 = 1-5%; 2 = 6-10%; 3 = 11-25%; 4 = 26-50%; 5 = >50% plot symptomatic.
7

48

Evaluation o f Fungicides for Control o f Dollar Spot in Creeping Bentgrass - 2003.
M a r k L G le a s o n a n d S a r a

./.

H o ll a n d

Trials were conducted at the Iowa Stale University Horticulture Station in Ames, Iowa. Creeping bentgrass was maintained at a 0.150inch cutting height. Fungicides, selected for activity against brown patch, w'ere applied using a modified bicycle sprayer at 30 psi and a
dilution rate of 5 gal per 1000 sq ft. The experimental design was a randomized complete block with four replications. All plots
measured 4 ft x 5 ft. Spray applications were initiated on June 30. This w'as followed by re-applications at recommended intervals until
August 20. Visual estimates were made of percent disease severity for dollar spot at approximately 10-day intervals starting on July 27.
Data were analyzed using the GLM procedure in SAS, and mean separations were determined using Fisher's protected LSD at P<0.05.
Disease pressure was low to moderate due to dry conditions throughout July 2003. Most of the tested products suppressed dollar spot
significantly (P<0.05) in comparison to the unsprayed check, with the exception of Endorse. This product provided no better control than
the unsprayed check. No phytotoxicity symptoms were observed during the trial.

Table 1. Dollar spot trial - 2003 Iowa State University Horticulture Research Farm. (Penncross creeping bentgrass) Plot size: 20 ft“ (4 ft

x 5 ft): 4 plots per treatment

Trt #

Company

1
2
3
4
5

Check
BASF
BASF
BASF
BASF

6
7

BASF
Cleary
Cleary
Bayer
Bayer
LSI) (0.05)

8

9
10

Product

Rate/1000 ft2

Interval
(days)

27 Jul
4.1

Emerald 70WG
Emerald 70WG
Insignia 20WG
Emerald 70WG ROTATE
Insignia 20WG and
Propiconazole Pro 1.3 MC
Endorse 2.5WP
Spectra 90WDG
26GT 2SC
Bayleton 50DF

0.13 oz
0.18 oz
0.9 oz
0.13 oz +
0.9 oz
1.0 11 oz
4 oz
4 oz
4 fl oz
0.5 oz

14
21

14
14
14
14
14
14
14

0.0
0.0
0.0
0.0

Dollar spot (%)
15 Aug
6 Aug
7.5
0.0 c
0.0 c
0.0 c
0.1

15.7
3.1
3.7

0.5
0.9

2.2

1.5
16.7

3.6

0.0

0.0

0.1

1.7

5.2

10.7

0.0
0.0
0.0

0.0
0.0

2.0

2.5

0.2
0.0
0.6

6.2

3.7

3.7

1.6

Product applications were rotated on a 14-day interval (Emerald June 30 and July 28; Insignia July 14 and August 11).

49

23 Aug

10.0
0.0
0.0

5.5
1.4

Nitrogen Deficiencies in C reeping Bentgrass can be Identified Through Rem ote Sensing
J. K . K r u s e , N . E . C h r i s t ia n s a n d M . H . C h a p lin

Turfgrass managers continually monitor their fertilization and irrigation programs to ensure optimal appearance while minimizing kisses
to the environment and maximizing profit. Characterizing the spatial variability of nutrient and moisture status across a golf course or
large sports facility requires careful observation and collection of many soil and tissue samples. Optical remote sensing techniques have
been shown to be valuable tools in identifying stressed plants quickly and reliably through the use of various vegetative indices derived
from reflectance data collected from the crop canopy. Extensive research has been conducted investigating vegetative indices as they
relate to the nutritional and moisture status of various agricultural crops with intriguing results. Currently, most of the research has
investigated the ability of vegetative indices to identify plants responding to a variety of biotic and abiotic stresses. The use of remotely
sensed data may prove to be a valuable tool in the modification of traditional irrigation and fertility programs to reduce inputs and
improve environmental quality.
The objectives of this research were to: 1) Evaluate various indices reported in the literature as tools for identifying moisture and nutrient
stressed turf, 2) Develop new indices to be used in detection of moisture and nutrient deficiencies, and 3) Determine differences in
spectral response of Creeping Bentgrass, Kentucky Bluegrass, and Perennial Ryegrass.
Tins work was conducted at the Iowa State University Horticulture Research Station, Gilbert, Iowti, on a ‘Penncross’ creeping bentgrass
putting green (USGA, 1993). Plots were 1.52 m x 1.52 m and arranged in a randomized complete block design with four replications per
treatment. Nitrogen fertilizer treatments were applied with a backpack sprayer at 0, 12.2, and 24.4 kg*ha-1 every 15 d (14 total) as urea
in solution. Spray volume was 122.5 mL m-2 and pressure was 207 kPa. In addition to N. all plots received uniform phosphorous (P) at
2.44 kgdia-1 as phosphoric acid and potassium (K) at 5.0 kgha-1 as potassium chloride. Treatments were applied from March 25, 2002
to October 8, 2002. Plots w'ere mowed four times each week at a height of 3.8 mm and clippings were removed. Irrigation was applied
when the soil surface was dry to the touch to prevent drought stress.
Turf evaluation of quality was made on a twice monthly basis, coinciding with collection of remotely sensed data. Quality w^as
ranked on a scale of 1 to 9; with 9 = best. 6 = lowest acceptable and 1 = worst. Optical remote sensing data w'as collected twice monthly
using an OceanOptics SDI000 spectrometer mounted on a self contained cart equipped with a hood to block out ambient sunlight and
halogen bulbs to provide a consistent source of illumination on the turf. This system was designed to eliminate the problems typically
associated with differences due to shade, which is a common occurrence on many turfgrass areas. The spectrometer was calibrated to
measure reflectance from 450-1050 nm with a resolution 1.0 nm.
The following growth and stress indices were evaluated for their relationship to plant chlorophyll content, turfgrass quality, and nutrient
concentration:
1. Normalized Difference Vegetation Index (NDVI) computed as R m ) - R a)()/R m ) + R m )
2. Infrared/Red (IR/R) computed as /?7S(//?600
3. Far Red/Infrared (FR/IR) computed as R ^ / R i m
4. AREA computed as total area under each reflectance curve from 450 to 1050 nm
5. Nitrogen Stress Index (NSI) computed as the total area under the reflectance curve from 450 to 1050 nm divided by ( R ^ R 1W)
or [(AREA) / (FR/IR)]
Tissue was harvested once a month following collection of remotely sensed optical data and analyzed for plant nutrient content using
standard Total Kejhdahl Nitrogen and Inductively Coupled Argon Plasma Spectroscopy plant analysis procedures.
Regression analysis was used to test linear relationships between vegetative indices and tissue nutrient concentrations. The general linear
models (GLM) procedure and the Fisher’s least significant difference (LSD) option of Statistical Analysis Software (SAS) were used to
determine differences in tissue nutrient concentration. A correlation procedure was used to investigate relationships between the
vegetative indices and tissue chlorophyll content, turfgrass quality, and biomass production.
Results
In general, plots that receive low rates of N are characterized by increased reflectance in the visible region of the spectrum (450 to 700
nm) and decreased reflectance in the far red and ncar-IR regions of the spectrum (700 to 1050 nm) when compared to plots receiving
adequate N fertilization. Treatment effects on tissue N concentration as a result of N treatments w'ere observed at all sampling dates (data
not shown). The tissue N concentration ranged from 22.3 g/kg in plots receiving no N to 45 g/kg in plots receiving N at a rate of 24.4
kg*ha-l. Regression analysis of the NSI, NDVI, IR/R, and FR/IR against N concentration resulted in significant linear regressions (r2 =
0.34 to 0.86) for all sampling dates in 2002 (Table 2). The AREA index produced significant regression coefficients at four of the five
sampling dates (r2 = 0.44 to 0.61) (Table 1). We found correlations between turfgrass quality and biomass production for all indices
throughout the study (Table 2). Chlorophyll content was correlated with all vegetative indices with the exception of AREA (June 25) and
NDVI (September 2) (Table 2). Correlation coefficients were stronger between NSI and quality, chlorophyll content, and biomass than
for any other vegetative index on both dates with the exception of chlorophyll content on June 25 (Table 2). Treatments did not have an
effect on P, K, or micronutrient concentrations in the turfgrass tissue (data not shown).

50

Discussion
The successful implementation of a remote sensing model for analyzing the N status of turfgrass plants requires that the model be
accurate throughout the duration of the season. One measure of this is the indexes ability to explain a majority of the variation in the
model, as indicated by the regression coefficients. Our results demonstrate that NS1 values generated from remotely sensed, spectral data
can be used to assess turfgrass N stress in creeping bentgrass. We contend that dividing the area under the curve by FR/IR magnified the
response to N concentration due to the sensitivity of FR/IR to the N in the plant tissue and produced regression coefficients that
consistently explained a majority of the variability in the model throughout the season (r2 = 0.62 to 0.86).
The NDVI is sensitive to changes in turfgrass biomass and turfgrass quality, which is consistent with our findings. Previous research has
established that the relationship between NDVI and various biological parameters such as biomass can be adversely affected during midseason. This is supported by our results in which the NDVI failed to account for a majority of the variability on two of the five sampling
dates (July 22 and September 22) (Table 2). By comparing NDVI to the other vegetative indices, we found that in all cases the 1R/R.
FR/IR, and NSI indices resulted in stronger correlations than NDVI (Table 2).
The AREA index failed to explain the variability due to N-treatments in the model as well as the other indices in this study. This was
surprising to us as changes in the N rate seem to have a significant impact on the height of the reflectance curve, which in turn would
affect the total area under the curve. It appears that combining the AREA with the FR/IR index that monitors changes in the “blue shift"
as we have done with the NSI has succeeded in improving the reliability of the index during the mid- to late-season when proper
fertilization is critical. We feel that the success of the NSI is due in pan to the use of an auxiliary source of irradiance instead of ambient
sunlight, which allowed us to eliminate the variability caused by constant changes in the atmosphere and the angle of incidence.
The goal of remote sensing research has been to identif y characteristics of the reflectance spectrum that are sensitive to specific changes
in plant stress. While it is clear that we have been able to identify the point at which plants become stressed, it has not been as easy to
identify the causal agent. Development of a remote sensing tool that can accurately identify N-stressed turfgrass areas will assist
turfgrass managers in reducing fertilizer inputs and improving the overall quality of their facilities. We feel that the NSI proposed here
has succeeded in improving sensitivity to changes in N stress throughout the season. The NSI may prove as a valuable tool for quickly
assessing the N status of creeping bentgrass greens and allowing for site-specific applications of fertilizer. Utilization of site-specific
technology for fertilizer applications would help improve fertilizer-use efficiency thereby, reducing the risks of nutrient runoff and
groundwater contamination. With future work, the NSI has the potential to change the way we currently approach remote sensing
problems and improve the overall success.
In addition to the results discussed here, several moisture studies have been conducted investigating the use of the remote sensing
equipment to evaluate the moisture status of' turfgrass plants growing under fairway conditions on a golf course. Work is also being done
to evaluate the influence of soil amendments on spring green-up and heat stress on the reflectance qualities of a turfgrass stand.

51

Table I. 7Tic r values for vegetative indices regressed against nitrogen status of ‘Pcnncross’ creeping bentgrass on a USGA sand based
green for five sampling dates during 2002 at the Iowa State Horticulture Research Station, Gilbert, IA. (n = 12).
Sampling Date
Vegetative
Index
NSI

28-May

25-June

22-July

21-Äug.

22-Sept.

0.76***

0.86***

0.76***

0.62**

0.80***

NDVI'

0.65**

0.81***

0.46*

0.66**

0.48*

IR/Ry

0.82***

0.79***

0.34*

0.78***

0.53**

FR/IRX

0.77***

0.81***

0.56**

0.58**

0.78***

ns

0.44*

0.45*

0.61**

0.48*

Area"

ns,*,**,*** Nonsignificant or significant at P < 0.05, 0.01, or 0.001, respectively.
'Normalized Difference Vegetation Index = (Rm )~ R m ))R R m ) + R w oh
yInfrared/Red = Rm )/R<m .
'Far Rcd/Lnfrared = R M5/R lm .
" Area = Area under reflectance curve calculated from 450 to 1050 nm.
'Nitrogen Stress Index = (AREA)/( R M5/R 1M)).

Table 2, Correlation coefficients for reflectance vs. visual quality, chlorophyll content and biomass of creeping bentgrass growing on a
USGA sand based green at the Iowa State Horticulture Research Station, Gilbert. IA in 2002 (n = 12).______________
NDVI7

IR/RV

FR/1RX

AREA"

n s iv

25-June
Quality

0.92***

0.87***

-0.95***

Chlorophyll content

0.63*

0.67*

-0.60*

Biomass

0.85***

0.83***

-0.89***

0.62*
ns

0.96***
0.58*

0.60*

0.91***

0.67*

0.77**

2-September
Quality
Chlorophyll content
Biomass

0.76**

-0.75**

ns

0.58*

-0.70*

0.63*

0.73**

0.74**

0.79**

-0.81**

0.70*

0.82**

0.65*

ns,*,**,*** Not significant or significant at P<0.05, 0.01, or 0.001, respectively.
'Normalized Difference Vegetation index (NDVI) - (R m ) - R m ))/(R m ) + R(,oo).
yInfrared/Red (IR/R) = R m)/R m ).
'Far Red/Infrared (FR/IR) = Rm /Rim" AREA - Area under reflectance curve calculated from 450 to 1050 nm.
'Nitrogen Stress Index (NSl) = (AREA)/( R 695/R 1M))

52

Evaluation of Phosphorus Rate and M ixing Depth on the Growth and Establishm ent o f
p r a te n s is L. in Sand-based System s
.S'. K .

L ee, D .

.Min n e r ,
D

N . E. C h r i s t ia n s , a i u l H .G . T a b e r

Introduction
Phosphorus is highly immobile in most soils and is often a limiting factor for establishment (Ben-Gal and Dudley, 2003). Mixing
phosphorus through the sand profile is thought to increase P availability and improve establishment during the first year of growth.
Phosphorous application to lawns in Minneapolis, MN has been regulated. Phosphorus movement in sand based systems has not been
well documented and the potential of phosphate movement into drainage systems is not understood. This study was conducted to
evaluate 0. 146 and 293 kg P*ha 1at placement depths of 0, 7.6, 15.2, and 22.9 cm in a sand-based system.
Materials and Methods
This study was conducted for 12-weeks in a greenhouse at Iowa State University in Ames, Iowa. The first study was conducted from
November 2002 to January 2003 and the second conducted from March 2003 to June 2003.
Local mason sand that met the United States Golf Association (USGA) specification was used as the growing medium (USGA Green
Section Staff, 1993). The sand w^as packed into a 7.62 cm diameter polyvinyl chloride (PVC) pipe lined with a clear plastic tube. Total
energy of 3.03 J»cm ^ was used for compaction of the root zone. The PVC pipe was capped at the bottom and the plastic tube tied off at
the base with fine holes punched to facilitate drainage. The root zone depth was 30.5 cm and the holding tube was 38.1 cm long. The
columns w;cre sodded with mature sod of ‘Unique’ P o a p r a te n s is L. Greenhouse day/night temperature was 22.2/19.4 °C. The average
light level during the 16 hr photoperiod in the greenhouse was 833.8 microEinsteins • m" • see !.
Pellett and Roberts (1963) nutrient solution designed for cool-season grasses, minus P, was used to provide proper levels of other
essential elements in the root zone. Triple superphosphate (CaifLPCLb) was used as the P source. Phosphorus w^as evaluated at 0, 146
and 293 kg P«ha 1and at four mixing depths (0, 7.6. 15.2, and 22.9 cm). Phosphorus w>as applied on November 4, 2002, and March 17.
2003. Grass clippings were taken from each tube at approximately two-week intervals. The clippings were oven-dried at a temperature
of 67 °C for 24 h and weighed. At the end of the study, root dry weight w>as determined by washing and oven-drying root samples at 67
°C for 24 h (Steyn, 1959). Organic matter weight for roots was also measured at the end of the study. Oven-dried roots were ashed at
490 °C for 8 h in a muffle furnace (Jones and Case, 1990) and then weighed to determine organic matter. Total clipping P concentration
was determined by using a modified Vanadomolybdophosphoric Acid Method (Kuo, 1990). This procedure was conducted by using a
spectrophotometer (Spectronic 20+) following dry ashing at 490 °C in IN aqua-regia. All leachate solution was collected from a cup
under the PVC pipe for final nutrient analysis. Total P leaching concentration was analyzed by using a modified
Vanadomolybdophosphoric Acid Method (Kuo, 1990) and a spectrophotometer (Spectronic 20+) was used to conduct this procedure.
The experimental design was a randomized complete block design with a split-plot arrangement. The treatments were whole columns
with a factorial arrangement of P rate and mixing depth as subplots, replicated four times. The data were analyzed using the t-test
procedures and mean separation was performed by the Standard Error of Difference (SED) method of the Statistical Analysis System
(SAS, 1987). PROC MIXED w>as used for multiple factor analyses of variance.
Results and Discussion
No difference was found in clipping dry weight, root dry weight, and root organic matter (Table 1).
No differences were found in P leached from the columns (Table I ). This varies from the observations of Larry (1999), who found that P
leaching increased from 1 to approximately 14 mg*L 1with increasing P rate from 0 to 253 kg*ha 1in a sand-based system. This may
also have been due to the very high irrigation level of 8.75 cm per week in the Larry study. Bacon and Davey (1982) and Kargbo et al.
(1991) found that P mobility and availability is affected by relatively high moisture and high irrigation frequency which may lead to
higher P loss than low moisture and frequency irrigation, especially in sand-based systems.
Grass treated with 293 kg P»ha-1 produced 2-30% more P in the tissue than treatments of 146 kg P*ha-1, with the exception of the
application placed at the 15.2 cm mixing depth (Table 2). Surface applications of 146 and 293 kg P*ha~l produced 8-10%' and 16-20%
more P in tissue than subsurface applications, respectively. However, no difference was found between applications applied to the
surface and the 7.6 cm mixing depth. Phosphorus sufficiency level in mature leaves range from 2000-5000ppm (Mills and Johns, 1991).
The treatments in this study produced sufficient P tissue levels ranging from 2277 ppm for 146 kg*ha-1 at the 15.2 cm mixing depth to
2963 ppm for surface applied P at a rate of 293 kg*ha-l. The untreated control resulted in tissue levels of 1758 ppm P, which is below
the sufficiency level for mature leaves.
Under the conditions of this study, there was no advantage to incorporating P in a sand-based media for Kentucky bluegrass sod
establishment. Surface applied P increased the tissue levels of P, but had no effect on growth parameters.

Table 1. Summary of analysis of variance from the 2002 and 2003 greenhouse study about evaluation of phosphorous rate and mixing
depth on the growth and establishment of p o a p ra u m sis L. in sand-based systems.__________________________
Total dipping
Root dry
Root organic
Total P in
Total
dry weight
matter
leached P
weight
clippings
Source
df
$
4
**
1
NS
NS
Year
**
Treatment
8
NS
NS
NS
NS
Rate

1

NS

NS

NS

NS

**

Depth

3

NS

NS

NS

NS

**

Rate * Depth

3

NS

NS

NS

NS

NS

Year * Treatment

8

NS

NS

NS

NS

NS

*, ** Significant at the a = 0.05 and 0.01 probability level, respectively. NS = not significant

Table 2. Mean clipping phosphorous (P) (mg»kg^) of ‘Unique’ P o a

Kaie tkgma *

p r a te n s is

L. with factors P rate and mixing depths averaged over

Mixing depth (cm)
0

7.6

15.2

22.9

Control

1758

—

—

—

146

2498

2502

2277

2308

293

2963

2871

2475

2556

Ü7Ü»*/
103y
130'

SED : Standard error of difference.
y Value means standard error of difference lor comparison between control and the other treatment.
x Value means standard error of difference for comparison among all treatments except control.

References
Bacon, P.E., and B.G. Davey. 1982. Nutrient availability under trickle irrigation: 1. Distribution of water and Bray no. I phosphate. Soil Sci. Soc. Am. J.
46:981-987.
Beard. J.B. 1973. Turfgrass: Science and culture. Prentice-Hall, Inc., Englewood Cliffs, NT.
Beauchemin, S., R.R. Simard, and D. Cluis. 1998. Forms and concentration of phosphorus in drainage water of 27 tile-drained soils. J. Environ. Qual.
27:721-728.
Ben-Gal, A. and L.M. Dudley. 2(X)3. Phosphorus availability under continuous point source irrigation. Soil Sci. Soc. Am. J. 67:1449-1456.
Christians, N.E. 1998. Fundamentals of turfgrass management. Ann Arbor Press, Inc.. Chelsea, Ml.
Havlin, J.L., J.D. Beaton, S.L. Tisdale., and W.L. Nelson. 1999. Soil fertility and fertilizers an introduction to nutrient management. Prentice Hall, Inc..
Upper Saddle River, NJ.
Jones, J.B., Jr. and V.W. Case. 1990. Sampling, handling, and analyzing plant tissue samples. P. 389-419. In D.E. Kissel cl al. <ed.) Soil testing and plant
analysis. SSSA Spec. Publ. 3. SSSA, Madison, WI.
Kargbo, D., J. Skopp, and D. Knudsen. 1991. Control of nutrient mixing and uptake by irrigation frequency and relative humidity. Agron. J. 83:10231028.
Kuo, S. 1990. Phosphate sorption implications on phosphate soil tests and uptake by com. Soil Sci. Soc. Am. J. 54:131-135.
Larry, M.S. 1999. Nitrate and phosphorus leaching and runoff from golf greens and fairways. United States Golf Association. 1999 Annual Report.
Mills, H.A., and J. B. Jones, Jr. 1991. Plant analysis handbook II. MicroMacro publishing, Inc. Athens, Georgia.
Pcllett, H.M., and E.C. Roberts. 1963. Effects of mineral nutrition on high temperature induced growth retardation of Kentucky blucgrass. Agron. J.
55:473-476.
SAS. 1987. SAS/STAT User’s Guide. Version 6. Statistical Analysis System Institute. Inc., Cary, NC.
Steyn. W.J.A. 1959. Leaf analysis. Errors involved in the preparative phase. J. Agric. Food Chem. 7:344-348.
United States Golf Association Green Section Staff. 1993. USGA recommendations for a method of putting green construction. USGA Green Section
Record. 1-3.

54

Evaluation of V arious Slow -release Nitrogen Sources for Growth and Establishm ent o f
p r a te n s is L. on Sand-based Systems
S.K. Lee, D.D. Minner and N.E. Christians
Introduction
Slow release fertilizers were initially developed to provide a more consistent release of nitrogen over a longer period. This reduces the
number of applications per year and allows for higher rates of product to be applied in a single application. Because slow release
fertilizers release smaller amounts of nutrient over longer periods of time, they have not been considered as a primary choice for rapid
establishment of turfgrass. Establishing grass on sand based systems is problematic because nitrogen is easily leached from the system
and soluble N sources often need application every 7 days to grow-in these sand-based fields. The goal of this project is to determine if
various slow release N sources affect the rate of turfgrass establishment. It is also not clear if high rates of slow release N sources can be
mixed into the sand media to improve turf establishment.
Materials and Methods
Six nitrogen sources were evaluated: Nitroform (38-0-0), Nutralcnc (40-0-0), Organiform (30-0-0), Sulfur coated urea (SCU), Urea, and
Milorganite. Local mason sand that meets USGA specification was used as the growing media. The sand materials were packed into a
3-inch diameter PVC pipe lined w ith 2.7-inch diameter clear plastic tubing. The plastic liner was removed for the measurement of roots
and replaced in the PVC tubes. The PVC pipe was capped at the bottom and the plastic tube tied off at the bottom with line holes
punched to facilitate drainage. The root zone depth was 14 inches and the holding tube was 15 inches. Each fertilizer, except urea, was
mixed into the top 2 inches of the root zone media at rate of 2 and 4 lbs of N per 1000ft2, respectively. Urea treatment w'as applied at the
surface of the media at 0.16 and 0.33 lbs of N per 1000 ft2, weekly giving a total of 2 and 4 lbs of N per 1000 ft2 during the 12 week study
period, respectively. The root zone media was either seeded or sodded with 'Limousine' Kentucky bluegrass and watered to field
capacity on November 20, 2001. The study was conducted in the research greenhouse at the 1SU Horticulture Department, Ames, 1A.
Turf color, root length and clipping yield was recorded every week and root dry weight was estimated by washing sand from the roots
and oven drying the roots at the termination of the study. The experimental design was a randomized complete block design with three
replications. The data were analyzed using the t-test procedures, and the mean separation w>as performed by standard error of differences
(SED) method of the Statistical Analysis System (SAS, 1987).
Results
There was an interaction between N source and establishment type and between N rate and establishment type for total clipping yield
(Table 1). Urea applied to the seeded pots produced 109-230% more clipping dry weight than other N sources applied to the seeded pots.
However, Milorganite applied to the sodded pots created 26-55% more clipping dry weight than other N sources (Table 2). A significant
interaction existed between N sources and establishment type for root dry weight and root length at the end of the study (Table 1).
Milorganite applied to the seeded pots produced 9% more root length than organifrom applied to the seeded pots, although there was no
difference between urea and milorganite. Urea produced 13-22%/ more root length than other N sources. Milorganite formed 25-45%
more root dry weight than urea applied to the seeded pots (Table 2). However, no difference for root dry weight was found between
milorganite and urea in the sodded pots. There were differences for turf color between treatments in the seeded pots and in the sodded
pots, even though no difference w?as found between rates in the sodded pots. This w^as not changed until 12 WAP.

Table 1. Summary of analysis of variance from 2001 greenhouse study on the evaluation of 6 nitrogen sources for establishment and

Source of variance

elf

Total clipping
yield

Root length at the
end of the study

Turf color at
the end of the
study

Nitrogen Sources (NSO)
Nitrogen Rate (RATE)
Establishment Type
(TYPE)
NSO* RATE
NSO*TYPE
RATE*TYPE
NSO*RATE*TYPE
: Significant at the a

5
1

**
*

NS
NS

**

NS
NS

1

**

**

**

NS

NS
**

NS
*

NS
NS

NS

-

5
5
1
5
0.05 and 0.01

XX

NS
NS
NS
NS
probability level, respectively. NS = not significant.
x

X

55

Root dry weight

X

NS
NS

Table 2. Mean root length and root dry weight of ‘Limousine’ P o a p r a te n s is L. with factors N sources and type of establishment
averaged over replications and both levels of N rates at the end of the study.____________________________________
Total clipping
Root length (cm) at the end
Root dry weight (g*in~)
Seed
Sod
125.05 '
428.41
Nitroform
114.21
520.05
Nutraiene
485.74
Organi form
105.18
166.13
470.39
scu
147.17
665.47
Milorganite
347.60
529.97
Urea
57,.16
SEDV
L Each mean was calculated from 6 observations (three
Standard error of difference.

Seed
19.58
19.92
18.80
20.27
20.45
19.77

Seed
13.40
15.64
14.17
13.29
20.99
11.55

Sod
23.00
23.42
22.92
21.28
20.88
26.80

1.49
replications * two N rate levels).

Sod
13.76
14.50
16.53
17.32
12.11
1 1.60
2.48

Figure 1. Mean turf color per unit surface area of ‘Limousine’ P o a p r a te n s is L. by N rate and type of establishment. Each mean was
calculated from 18 observations (three replications ii:6N sources). The vertical bar represents the standard error of difference
(SED). WAP means week alter planting.
10.0

9.0
SED=0.3

u

jg
"o
SJ
Cm

Lm

3

Cft
OJ
£
£
I

8.0

TJ
3
3

6.0

+S

5.0

I

7.0

o

C /3

QJ
pC

H
cn
sO

SED=0.2

4.0

O-

o

3.0

2.0
1.0

2lb N per 1000 sq.ft - Seed

—

4ib N per 1000 sq.ft - Seed

—■ — 41b N per 1000 sq.ft - Sod

2l b N per 1000 sq.ft - Sod

0.0
WAP 8

WAP 9

WAP 10

56

WAP 11

W AP 12

Cation Ratios and Soil Testing Methods for Sand-Based G olf Course Greens
S t. J o h n . N ic k

CHenry T a b e r

This research is being funded by a grant from the United States Golf Association to study the soil testing methods of sand-based greens
and Ca/Mg/K fertilizer recommendations. This research was introduced in last year's field day report. At this time, there is no data or
results to present in this report. This report is to reintroduce the background, objectives, and goals for those who have did not see last
year's report.
Introduction:
Sands have low cation exchange capacities (CEC), which means applying the correct amount of fertilizer to provide adequate plant
nutrition without causing nutrient leaching can be difficult. To further complicate the problem, the sand used for greens and athletic field
construction is often calcareous. Calcareous sands will usually have higher pH values, which can lead to some nutrient deficiencies.
Moreover, testing calcareous sands to determine nutrient levels and make fertilizer recommendations can be problematic. Many standard
tests that are used today will dissolve calcium carbonate particles and change some of the values measured like Ca content and CEC.
Objectives:
1. To evaluate and correlate several existing soil extraction methods with tissue analysis to determine which type of extractant is
best for sand based turfgrass systems.
2. To modify, if necessary, existing extraction methods to better suit turfgrass soil types.
3. To better understand how the BCSR theory and Ca/Mg/K ratios apply to turfgrass systems.
4. improve current recommendations for Ca/Mg/K fertilization of turfgrass.
Research Methodology:
Currently, several soil samples have been processed by many different testing methods to evaluate different procedures. Also, a
greenhouse project has been started to evaluate different Ca to Mg ratios. Two more greenhouse projects are being initiated to look at
different Ca:K and Mg:K ratios.
Goals and Expected Results:
To develop a set of standard methods and models to be used in analyzing turfgrass soil samples, especially for calcareous sand samples.
Improved understanding of Basic Cation Saturation Ratio Theory and Ca/Mg/K ratios used for fertilizer recommendations.

57

Effect of plastic m ulching on color retention on seeded Berm udagrass varieties during fall
season.
DA). Minner & F.J. Valverde
This study was conducted from June 30 to November 15, 2002 at the Horticulture Research Station in Gilbert Iowa. Five different
varieties of Bermudagrass (C ynocion d a c ty lo n ) and one zoysiagrass (Z o ysia ja p ó n ic a ) were evaluated under different plastic mulches for
color retention during the fall season.
Warm season grasses arc known to lose color as temperature declines and when frost occurs. Some varieties of bermudagrass seem to be
more efficient in retaining the green color. Color retention in the fall is a desirable trait for extending the growing season. Protective
covers have been used to reduce winter injury in both cool and warm season grasses. The effect of light on fall color loss (bleaching) has
not been evaluated for bermudagrass turf.
Objective
Clear and black plastic covers were compared with no cover to determine the effect of light on Bermudagrass color loss at the onset of
winter dormancy.
Methods
The study was seeded on June 30lh. All six cultivars (Table 1) were seeded at a rate of 3 lbs/1000 sq.ft. The trial follows a split block
design with 3 replications (blocks), 3 covers (split plot) and 6 treatments (varieties) for a total of 54 small plots. Plots were fertilized at 2
lb/1000 sq.ft of N, P and K of each nutrient during the summer. The first mowing was done in the middle of August and before each
rating session.
Table 1. Bermudagrass varieties and covers used to evaluate color retention.

Varieties
1
2
3
4
5
6

Covers
1 Black (4 mil)
2 Clear (4 mil)
3 No Cover

Srx9554
Primo
Yukon
Riviera
Sr9500
Zoysia *

* Not a Bermudagrass

By the first week of September, it was considered that the grass had reached its maximum growth and color. Color ratings were done
September 14. October 25, and November 08.
Tarps were placed on top of the grass by October 15, just a few days before the first night w ith freezing temperatures. Tarps were
removed October 25 for 2 days and replaced on October 27. Tarps were removed again on November 8 for observation.
All varieties of Bermudagrass w'ere at least 95% ground cover before cold temperatures started to effect growth. Before the taips were
placed turf color was between 7 and 8 (Table 2).
Table 2. Color ratings observed in 6 varieties of warm season grasses during fall of 2002.
Black
Cultivar
Srx9554
Primo
Yukon

Clear

Uncovered

I4-Sep

25-Oct

8-Nov

14-Scp

25-Oct

8-Nov

14-Sep

25-Oct

8-Nov

7.0
7.2

7.8
7.8
8.0

4.7
4.7

7.2
7.0

6.5
6.3

4.7
4.7

7.2
7.2

2.3
2.7

1.0
1.0

4.7

7.8

6.0

7.8

4.0

1.0

4.7
4.7
4.7

7.5
7.5
7.0

7.3
7.0

5.8
5.2
5.0

7.3
7.3
7.2

3.0
2.7

1.0
1.0
1.0

7.8

Zoysia

7.5

8.0

Riviera
S1*9500

7.0
7.0

7.8
8.0

6.8
6.5

2.7

Color Scale 1-9, (9 dark green, 6 least acceptable green)

When averaged over varieties color differences are evident among plastic mulches and no cover (Table 3). On October 25 the black
plastic provided darker turf color compared to the clear plastic and no cover. One theory is that the lack of light prevents the breakdown
of chlorophyll during this transition period. By November 8 the clear plastic had better turf color than the black plastic, it appears that an
extended period of light blocking by the black plastic resulted in poor turf color. Since there were no temperature measurements reported
during this period, it cannot be clearly determined if light or temperature effect decline in turf color during the initial Bermudagrass
dormancy period.

58

Tabic 3. Color ratings given to varieties of hermudagrass under different covers (averaged over varieties)
Plastic_________ 14-Scp

25-Oct

8-Nov

Black
Clear
Uncovered

7.92
6.75
2.89

4.67
5.22

0.284

0.379

7.25
7.33
7.33

LSI) 0.05_______ 0.177

1.00

Color Scale 1-9, (9 dark green. 6 least acceptable green)

The type of plastic cover, and consequently the amount of light transmission, affected green color retention of hermudagrass. On
October 25 the black cover (reduced light to turf) provided greener turf than the clear cover (more light to turf). By November 8, this turf
color response was reversed, indicating that any turf color enhancement by light blocking is only a temporary response. Both tarps
significantly extended and protected the green color of the evaluated grasses during the fall season.
Table 4 shows the differences that occurred between Bermudagrass varieties for green color retention during the fall dormancy period.
Yukon maintained the most green color during the fall.
Quality ratings, temperature and radiation measurements will be available in future reports.

Table 4. Color ratings given to varieties of bermudagrass (averaged over covers)
Cuitivar________14-Sep

25-Oct

8-Nov

7.1 1

5.56

7.11

3.44
3.44
3.89

Zoysia

7.83
7.44

5.61
6.44
6.00

3.83

Riviera
Sr9500

7.28
7.06

5.78
5.72

3.56

LSI) 0.115

0.216

0.348

0.4646

Srx9554
Primo
Yukon

Color Scale 1-9. (9 dark green, 6 least acceptable green)

59

3.61

Bermuda Species Traffic Study
D .D . M i n n e r a n d F J . V a l v e r d e

This is the second part of a two year report. First year data appeared in the 2002 research report. Previous reports have shown that
bermudagrass can be seeded in the summer on severely warn areas of practice football fields to provide better turf cover at least in the
beginning of the fall playing season.
Objectives
To evaluate seeded and sprigged bermudagrass varieties to repair intensively trafficked areas of northern athletic fields, and to evaluate
mixtures of cool and warm season grasses in terms of color and coverage of turf through summer and fall.
Methods
Two independent trials were established at the Horticulture Research Farm in Ames Iowa on July 11, 2001 (data already presented) and
on June 14, 2002. Each trial was composed of 12 combinations of grass species, hybrids or individual species and 2 levels of traffic, for a
total of 24 treatments. The experimental design was a randomized complete block with split-plot arrangement. Whole plots consisted of
grass species and split plots were traffic levels. There were 3 replications for a total of 72 sample units of 2 ft x 12 ft. The species or
combinations of species and the establishment method used in 2002 appear in Table 1.
Table 1. Description of species and cultivars and establishment method for 2002.
Treat.

1
2
3
4
5

6
7
8
9

10
11
12

Species A
Yukon (Yk)
Primo (Prm)
Prime (Prm)
Primo (Prm)
Primo (Prm)
Primo (Prm)
Baby (Baby)
Westwood (Ww)
Quickstand (Qs)
Creeping Bentgrass (CB)
Perennial Rye (PR)
Kentucky Bluegrass (KB)

Planting time
Jun-12
Jun-12
Jun-12
Jun-12
Jun-12
Jun-12
Jun-12
Jun-12
Jun-12
Jun-12
Jun-12
Jun-12

Species B
—
—

Perennial Rye (PR)
Creeping Bentgrass (CB)
Kentucky Bluegrass (KB)
Perennial Rye (PRII)

Planting time
—
—

Jun-12
Jun-12
Jun-12
Aug-25

—

—

—

—

—

—

—

—

—

—

—

—

Establishment method
Seed
Seed
Seed
Seed
Seed
Seed
Sprigging
Sprigging
Sprigging
Seed
Seed
Seed

Traffic treatments were applied with a GA-SWC traffic simulator (Carrow et al.. 2001) on September 16 with 2 and 4 passes (2x & 4x)
each Monday, Wednesday and Friday until November 4. The variables measured were % turf cover, turf color and turf quality. Data was
collected monthly, from August 19 to November 4, 2002.
Results
Baby bermudagrass provided the most turf cover compared to all other grasses except PR on November 4 at the end of the traffic period.
At this same time all of the bermudagrasses, including ’Baby', had poor turf color because of frost. Adding KB and PR to ‘Primavera’
seeded bermudagrass improved turf cover at the end of the traffic period compared with ‘Primavera’ alone.
Table 2. Percent turf cover for various grass combinations and two levels of traffic.
Species
19-Aug
13-Sep
15-Oct
4-Nov
___________________________ Turf cover (% ) ________________________
Baby
100.0
85.0
90.8
78.5
CB
78.3
56.7
64.2
57.5
75.0
74.2
KB
80.0
65.8
PR
94.7
91.7
80.8
78.3
Prm
88.3
94.3
60.8
52.5
97.0
88.3
65.0
55.8
PrmCB
97.7
91.7
70.0
64.2
PrmKB
Prm PR
98.0
78.3
74.2
65.0
91.7
PrmPRII
95.3
68.3
62.5
64.2
99.3
80.0
75.8
Qs
WW
100.0
96.7
83.3
67.5
Yk
76.7
65.8
85.0
57.5
20.69
8.52
5.08
9.51
LSDo.o?
Traille Levels
81.94
2x
N.D.
N.D.
85.83
N.D.
4x
N.D.
59.72
46.25
3.48
3.88
LSDo.05

60

Table 3. Turf color observed in different species under traffic stress.
Species

19-Aug

15-Oct
4-Nov
13-Sep
Color*
Baby
7.0
7.0
4.3
1.5
7.7
5.9
CB
6.8
5.3
KB
4.7
8.2
7.6
6.3
9.0
PR
8.3
8.0
9.0
7.0
7.0
3.8
Prm
1.3
7.3
7.2
PrmCB
5.3
4.5
7.0
4.1
PrniKB
7.3
3.5
9.0
8.3
7.5
5.8
PrmPR
7.0
7.2
4.0
PrmPRII
4.3
7.0
7.5
4.8
1.9
Qs
7.0
7.8
wvv
2.3
1.2
7.7
Yk
5.3
2.5
6.5
1.09
0.99
0.56
0.63
LSD™*
Traffic Levels
N.D.
2x
N.D.
5.88
4.31
N.D.
N.D.
4x
5.02
3.47
l s d (M
I5
0.40
0.26
*Color ratings based on a scale of 1-10, where 10 is the most desirable green
and 6 the least acceptable; 1 is completely discolored grass
Literature cited
Carrow, R.N., R.R. Duncan, J.E. Worley and R.C. Shearman. 2001. Turfgrass traffic (soil compaction plus wear) simulator response of
P a sp a lu m va g in a turn and C y n o d o n spp. p. 253-258. In K. Carey (ed.). Int. Turf. Soc. Research J. Vol. 9.

61

Effect o f soil m oisture content and various traffic intensities on the perform ance o f K entucky
bluegrass.
I). I). Minner and
Objectives
To determine the effect that different traffic schedules have on Kentucky bluegrass ( P o a p r a te n s is ) performance. Specifically, we were
interested in determining if the same amount of traffic caused more injury if it was applied all-at-once (one day per week) or spread out
over time (a little each day).
And also, to study the interaction between traffic intensity and soil moisture for Kentucky bluegrass.
Methods
Two independent trials were conducted at the Horticulture Research Farm in Ames, Iowa during summer and fall of 2001 and 2002. Six
different traffic regimes were applied to Kentucky Bluegrass (Table 1 and 2) with a GA-SWC Traffic simulator (Cairow et al.. 2001).
The experimental design was a randomized complete block with 7 treatments and 3 replications. Each small plot was 2 ft x 12 ft. Traffic
simulation started on August 1 and ended on November 7 in 2001 and from July 29 to November 1 in 2002.
Table 1. Traffic schedule followed on Kentucky bluegrass during summer and fall 2001.
Number of passes/week
5 dispersed
10 dispersed
15 dispersed
5 concentrated
10 concentrated
15 concentrated
Control

Number of passes per day
Monday
1
2
3
0
0
0
0

Tuesday
1
2
3
0
0
0
0

Wednesday
1
2

Thursday
1
2

Friday
1
2

3
0
0
0

3
0
0
0
0

3
5
10
15

0

0

Based on the observations of the first year, a second split level (soil moisture) was added in 2002. The split factor was achieved by
splitting the area to be trafficked in 2 sections and by adding water to one section 20 minutes before traffic initiated (wet). The other
section received water alter traffic was finished (dry). The total amount of water applied was equal for both sections.

Number of passes/week
6 dispersed
12 dispersed
18 dispersed
6 concentrated
12 concentrated
18 concentrated
Control

Monday
2
4
6
0
0
0
0

Number of passes per day
Tuesday Wednesday Thursday
0
0
2
0
4
0
0
0
6
0
0
0
0
0
0
0
0
0
0
0
0

Friday
2
4
6
6
12
18
0

During 2001, rain sometimes made it too wet to operate the traffic simulator and it was impossible to strictly keep the traffic application
schedule. Traffic that was not applied as scheduled was transferred to the next available day. In 2002, the entire study area was tarped
during rain events to further control moisture during traffic. Percent turf cover was visually rated during the traffic period.
Results
Traffic intensity and periodicity influenced the performance of Kentucky bluegrass (Table 3). In both 2001 and 2002, the lowest turf
cover was observed at the highest traffic intensity (15 passes/ week) applied on a dispersed scheduled (Table 3 and 4).

62

Tabic 3. Turf coverage of Kentucky bluegrass observed under various traf fic scenarios during fail 2001.

Under traffic
Intoraitv
pass/wk

Periodicity

0

~

7‘AU«

28-Aug

11 -Sep

100

100

100

Recoven
8-Oct

24-Sep

21-Nov

20-jun

7-Aug

Turf cover (%)
100

100

100

100

100

95
96
85
83

95
92

100
97

100
99

85
63

96

96

85

55

78
67

93
80

5

e

100

98

96

97

5
10
10

d
c
d

100
95
92

93
93
73

93
88
73

95
77
75

15
15

c
d

88
87

63

62

50

57
52
63
c= all traffic concentrated one day of the week: d= traffic dispersed over the week

50
57

35

80

It seems that dispersing the traffic over the week does not allow the grass to recover before the following traffic event. This inten
only seems to be important at high traffic levels. Low traffic intensities do not show important differences between concentrated
dispersed traffic.
Table 4. Turf coverage of Kentucky bluegrass observed under various traffic scenarios during fall 2002.

7-Aug
Passes/wk Periodicity Condition
0
0
6
6
12
12
18

dry
c
c
c
c
c

18

c

6
6
12
12

d
d
d
d

18
18

d
d

Under traffic
10-Sep 28-Oct
Turf cover (%)

100.0
100.0
99.3
99.0
96.3
95.7
83.3

100.0
100.0
97.7
96.7
93.7

w et
dry

83.3
100.0
100.0
95.3
97.3
91.7

73.3
98.7
98.0
94.0
93.7

w et

88.3

w et
d ry
w et
dry
w et
d ry
w et
dry
w et
dry

91.0
78.3

88.3
76.7

12-Nov

100.0
100.0
95.0
93.3
90.0
81.7
75.0

100.0
100.0
98.3
97.7

50.0
95.0
95.0
91.7
86.7
81.7

20.0
98.7

50.0

88.3
86.7
45.7

98.0
83.0
55.0
30.7
5.7

c= all traffic concentrated one day of the week; d= traffic dispersed over the week.

Data of 2001 was averaged over traffic intensities to observe differences due to traffic periodicity (Figure 1). During the first month of
treatment, dispersed traffic caused more turf injury than concentrated traffic; later in the fall there was no difference. As indicated in the
methods, rain caused irregularities in the traffic schedule that may have influenced the results. For example, if it rained on Wednesday
evening then the 15 passes treatment would have received 15 passes on Friday all under wet conditions. However, the 15 passes
dispersed treatment would have received 5 passes on Monday and 5 passes on Wednesday under dry conditions with only 5 passes on
Friday under wet conditions. Turf trafficked under wetter conditions was expected to be injured more. Therefore, in the example above,
greater turf injury associated with concentrated traffic may have actually been influenced by the wet conditions. The converse was true if
it rained on Sunday. A Sunday rain resulted in wetter traffic conditions for the Monday and Wednesday dispersed traffic. By Friday, the
plot area had dried out and the Friday concentrated traffic would be applied under drier conditions. In 2002, the study area was tarped to
prevent rain from entering the study area and irrigation was controlled to provide wet and dry treatments.

63

Figure 1. Kentucky bluegrass turf cover based on traffic periodicity during fall 2001.

8 /7 /0 1

9 /7 /0 1

1 0 /7 /0 1

1 1 /7 /0 1

Date

Results were also averaged over periodicity to show differences only due to traffic intensity (Figure 2). By the end of the traffic period,
the highest traffic intensity reduced turf cover to less than half of the total area. Also, it was noted that there were larger relative
differences between 10 and 15 passes per week than from 5 to 10. The same was observed when comparing changes from 0 to 5 and from
5 to 10 passes weekly. This indicates that the decrease in turf cover may follow an exponential curve instead of a simple accumulative
trend. Turf may be able to tolerate or even recover rapidly form lower levels of traffic; however, traffic beyond a threshold level
degrades recovery potential because crowns and rhizomes are destroyed when soil is exposed. From a practical standpoint, it is
important that those who schedule athletic events understand and stay below the threshold traffic limit for a given field or suffer
irreversible traffic injury.
Figure 2. Turf coverage of Kentucky bluegrass observed as result of traffic intensity (0,5,10.15 passcs/wk with traffic simulator) during
fall 2001.

0 8 /0 7 /0 1

0 9 /0 7 /0 1

1 0 /0 7 /0 1

Date

64

1 1 /0 7 /0 1

For 2002, data was averaged over soil moisture and periodicity to show results affected to intensity (Figure 3). Results of the second trial
were very similar to the first year. Large visible differences were observed between treatments 12 and 18. Also, the larger decrease of turf
cover seems to occur towards the end of fall, after the middle of October.
Figure 3. Turf coverage of Kentucky bluegrass observed as result of traffic intensity (number of passes with the simulator) during fall
2002 .

8 /7 /2 0 0 2

9 /7 /2 0 0 2

1 0 /7 /2 0 0 2

1 1 /7 /2 0 0 2

Date

Figure 4. Turf coverage of Kentucky bluegrass as result of traffic periodicity during fall 2002.

CD

>

O

o

r3

H

Date

Figure 4 shows the effect of traffic periodicity; data was averaged over traffic intensity and soil conditions. Figure 5 shows the results due
to soil moisture only. No clear differences were observed in terms of periodicity when all information has been averaged. However,
isolated cases, especially at high intensities, indicated a disadvantage of dispersing traffic over time.

65

Figure 5. Turf coverage of Kentucky bluegrass as affected by soil moisture conditions during fall 2002.

8 /7 /2 0 0 2

9 /7 /2 0 0 2

1 0 /7 /2 0 0 2

1 1 /7 /2 0 0 2

Date

Soil moisture differences affected turf cover. Even at low rates of traffic, wet soil conditions showed the greater turf injury and less turf
cover. Differences were even greater at higher traffic intensities.

Conclusions
Turf cover decreased with increasing traffic.
Wet conditions caused more turf injury and less turf cover relative to dry conditions.
Concentrated traffic (all in one day) followed by a recovery period (6 days) had less turf injury and more turf cover than the same amount
of traffic applied as dispersed (traffic every other day ).
From a practical stand point it is important that those who schedule athletic events understand and stay below the threshold traffic limit
for a given field or suffer irreversible traffic injury.

Literature cited
Carrow, R.N., R.R. Duncan. J.E. Worley and R.C. Shearman. 2001 Turfgrass traffic (soil compaction plus wear) simulator response of
Paspalum vaginatum and Cynodon spp. P. 253-258. In K .Carey (ed.) int. Turf Soc. Research J. vol. 9.

Traffic tolerance of cool season seedling tu rf under simulated football traffic - Single seeding.
D .D . M i n n e r a n d F .J V a lv e r d e

Objective
To determine a grass species ability to establish from a single seeding during simulated traffic.
Methods
This study was conducted at the Horticulture Research Farm in Antes, Iowa. This trial was established in September 2002. lin e species
evaluated in this study were Kentucky bluegrass (Poet p r a te m is ) KB. perennial ryegrass ( L oliu m p e re n n e ) PR, tall fescue (F e stu c a
a n m d im ic e a ) TF. fine fescue (F e stu c a sp .) FF, creeping bentgrass (A g ro s tis p a lu str is ) CB, colonial bentgrass (A g ro s tis c a p illa r is ) Col,
velvet bentgrass ( A g r o s tis c a n in a ) VE and P oa su p in a PS. Each trial followed a split plot design with 4 replications, 8 treatments
(species) and 2 levels of traffic simulation.
The seeding rate (lb/1 OOOsq.ft) and the number of times that each plot was seeded appear in Table 1. The trial was seeded on September
4. 2002.
Table 1. Species and seeding rates used in the establishment trials.__________________________
Turf* species
Kentucky bluegrass
Perennial ryegrass
Tall fescue
Fine fescue

Seeding

Rate
lb/1000ft2
2

times
1
1
1
1
1
1
1
1

10
10
10
2
2
2
2

Poa supina

Creeping bentgrass
Velvet bentgrass
Colonial bentgrass

Traffic stress was applied with a GA-SWC traffic simulator (Carrow et al. 2001). Each species received two levels of traffic (split plot) as
indicated in table 2. Traffic started on September 11, 2002 and ended on November 8.
Table 2. Traffic schedule followed on Kentucky bluegrass during summer and fall 2002.

Number of passes/week
6 Concentrated
6 Dispersed

Number of passes per day
Monday

Tuesday

Wednesday

Thursday

0
2

0
0

0
2

0
0

Friday
6
2

Evaluation of percent ground coverage w^as done during and at the end of the growing season. Percent turf was also measured for the fall
trial at the end of spring season. During spring, no traffic w'as applied to the fall trials. Biomass production was determined at the end of
each trial (data not shown).
Results
All species germinated within 4 to 14 days after seeding. However, there was a clear difference in the speed of germination. Ryegrass
and all bentgrasses germinated well within a week. In contrast very few plants of Kentucky bluegrass and Poa supina were visible 2
weeks after planting.
Table 3 shows the evolution on turf coverage in plots seeded only one time. Low germination and the overall poor performance of most
species is due to the traffic that was applied almost immediately after seeding.

67

Observed turf coverage in turfgraiss species seeded one time in fall under 2 levels of simulated traffic.
Recovery
Traffic
May-29
Sep-13
Oct-23
Nov-8
Jul-3
Turf* species
Turf cover ( % )
29
0.0
2.9
1.1
Kentucky bluegrass
58
88
45.0
97
75.0
86.3
Perennial ryegrass
24.0
72
6.3
43.1
86
Tall fescue
10.1
5.8
72
7.5
85
Fine fescue
0.0
2.1
57
Poet s u p in a
4.0
37
3.4
70
63
Creeping bentgrass
25.0
5.1
2.1
52
43.8
6.6
29
Velvet bentgrass
32
32.5
6.5
2.3
53
Colonial bentgrass
5.91
6.09
11.65
10.01
8.15
LSD o,Q5
Traffic intensity
Concentrated
Dispersed
LSD,,,,,

n.d.
n.d.
NS

15
18
2.95

18
19
NS

58
47
5.82

73
66
5.00

Tall fescue was the only species that showed a slow beginning but was able to reach almost half of the area by the end of the first
growing season. Fine fescue did not establish well while traffic was applied but it did establish well after traffic stopped. Traffic
intensity (concentrated vs. dispersed) did not produce any constant result. As of April 2004, a second year of this study is being
conducted.
Literature cited
Carrow, R.N., R.R. Duncan, J.E. Worley and R.C. Shearman. 2001 Turfgrass traffic (soil compaction plus wear) simulator response of
Paspalum vaginatum and Cynodon spp. P. 253-258. In K .Carey (cd.) Int. Turf Soc. Research J. vol. 9.

68
_

Traffic Tolerance o f Cool Season Seedling T u rf Under Sim ulated Football Traffic-M ultiple
Seeding Trial
I). I). Minner and F.J Valve rde
Turfgrass species used for sport fields are often selected based on wear tolerance of a mature species. In reality, worn areas of the playing
field are seeded during the playing season resulting in traffic stress on seedling turf. Traffic tolerance of seedling turf and the eventual
recovery of the entire grass system have not been studied
Objective
To determine the ability of various grass species to establish during simultaneous multiple seeding and simulated traffic.
Methods
This study was conducted at the Horticulture Research Farm in Ames, Iowa. Two separate trials were conducted. An autumn trial was
seeded September 2002 to simulate fall football and a spring trial was seeded April 2003 to simulate spring soccer. The species
evaluated in this study were Kentucky bluegrass (P o a p r a te n s is ), perennial ryegrass (L o liu m p e r e n n e ), tall fescue (F estu ca a ru n d in a c e a ),
fine fescue (F e stu c a s p .), creeping bentgrass (A g ro s tis p a lu str is ), colonial bentgrass (A g ro s tis c a p illa n s ) Col. velvet bentgrass (A g r o s tis
ca n in a ) and P o a su p in a . Each trial followed a Split plot design with 4 replications, 8 treatments (species) and 2 levels of traffic
simulation.
The seeding rate (lb/1000sq.fi) and the number of times that each plot was seeded appear in Table 1. Each trial was seeded weekly for
six consecutive weeks after the initial seeding and traffic date. Traffic and seeding began on September 18 for the fall football trial and
on April 18 for the spring soccer trial.
Table 1. Species and seeding rates used in the establishment trials.______________________________________
Fall Seeded
Seeding
Rate
lb/1000ft2
times
6
2
10
6
10
6
10
6
2
6
2
6
2
6
2
6

Turf species
Kentucky bluegrass
Perennial ryegrass
Tall fescue
Fine fescue
P o a su p in a

Creeping bentgrass
Velvet bentgrass
Colonial bentgrass

Spring Seeded
Rate
lb/1000ft2
2

Seeding
times

10
10
10
2
2
2
2

6
6
6
6
6
6
6
6

Traffic stress was applied with a GA-SWC traffic simulator (Carrow et al. 2001). Each species received two levels of traffic (split plot) as
indicated in Table 2. Traffic started on September 18 and ended on November 8 for the fall trial. Spring traffic started on April 18 and
ended on June 27.
Table 2. Traffic schedule for fall 2002 and spring 2003.
Number of passes/week
6 Concentrated
6 Dispersed

Monday
0
2

Number of passes per day
Tuesday
Wednesday
Thursday
0
0
0
0
2
0

Friday
6
2

Evaluation of percent turf cover was used to evaluate a species performance during the traffic and recovery periods. Biomass production
was determined at the end of each trial (data not shown).
Results
Fall Traffic - Perennial ryegrass had the best turf cover during the fall trafficked establishment period. After the spring recovery period,
all of the species had at least 80% turf cover. Some of the fall trafficked seedlings recovered contributed to the spring recovery: however,
it w'as also apparent that some of the fall applied seed germinated in the spring and significantly contributed to the high turf cover ratings
at the end of the spring recovery period (Table 3). Since the end of the spring recovery period coincides with the start of the next
football season it is clear that perennial ryegrass, tall fescue and fine fescue would have produced the best playing conditions at the start
of the fall football season.

69

Table 3. Percent turf cover of species seeded multiple times in fall of 2002 under 2 levels of simulated traffic.

Sep-27
Turf species
Kentucky bluegrass
Perennial ryegrass
Tall fescue
Fine fescue

Traffic 2002
Oct-23

Nov-8
Turf cover ( % )
2.0
38.8
2.0
1.3

Recovery 2003
May-29
Jul-3

0.0
0.0
0.0
0.0

0.0
1.0

0.0

Creeping bentgrass
Velvet bentgrass
Colonial bentgrass
I SP no.

2.0
0.0

0.0
0.0

2.61

1.85

0.98

50
90
86
83
58
47
35
34
15.25

Traffic intensity
Concentrated
Dispersed
LSI) „

n.d.
n.d.
NS

7
7
NS

6
5
NS

64
57
NS

P o a su p in a

0.0

0.0

36.3
2.0
3.3

45.6
5.0
5.0

0.5

86
99
98
98
87
83
82
81
5.84

90
88
NS

Traffic intensity did not seem to affect species response; however, recovery seemed to be slig;htly better in plots with concentrated traffic
(Table 3). This indicates that when scheduling events it would be better to have several events on one field in a short period of time
followed by a lengthy recovery period (concentrated traffic) as compared with spreading out the same number of events over an extended
period with limited recovery time (dispersed traffic).
For the trial seeded in spring, results were a little different. Only tall fescue and perennial ryegrass were significantly better than the other
species by the end of the study. All other species showed around 75% of covered ground. Traffic intensity did not seem to have any
influence on species and their performance.
Tabic 4. Percent turf cover of species seeded multiple times in spring of 2003 under 2 levels of simulated traffic.
Traffic period Turf cover ( % )
Mav-29
Turf* species
Jul-3
11
74
Kentucky bluegrass
91
53
Perennial ryegrass
27
89
Tall fescue
34
79
Fine fescue
9
72
P o a s u p in a
44
74
Creeping bentgrass
19
78
Velvet bentgrass
24
76
Colonial bentgrass
5.03
7.65
LSD «.os
Traffic intensity
Concentrated
Dispersed
LSD mw

28
28
NS

79
79
NS

Summary
The following turfgrass species were ranked from best to worst according to establishment during traffic stress:
Perennial ryegrass > Tall fescue >Fine fescue = Kentucky bluegrass = Supina bluegrass > Bentgrass
The study will be repeated in 2004.

Literature cited
Carrow, R.N., R.R. Duncan. J.E. Worley and R.C. Shearman. 2001 Turfgrass traffic (soil compaction plus wear) simulator response of
Paspalum vaginatum and Cynodon spp. P. 253-258. //? K .Carey (ed.) Int. Turf Soc. Research J. vol. 9.

70

Perform ance of Established Cool Season G rasses U nder Simulated Football Traffic
D .D . M i n n e r a n d F J . V a l v e r d e

Objective
To evaluate the traffic tolerance of cool season grasses when mature species are provided with seed in the presence of traffic.
Methods
This study was conducted at the Horticulture Research Farm in Ames, Iowa. The trial was seeded in September 2000 to address questions
on a mature and fully established system. The species evaluated in this study were Kentucky bluegrass (P o a p r a t en s is ), perennial
ryegrass (L o lim n p e re n n e ), tall fescue (F e stu c a a ru n d in a c e a ), line fescue (F estu ca s p .), creeping bentgrass (A g ro s tis p a lu str is ), and P o a
su p in a . The experimental design was a Randomized Complete Block with a split plot arrangement. There were 4 replications, 6 species
(whole plots) and 2 levels of traffic simulation (split-plots). Each grass species had 100% turf cover before traffic treatments were
initiated in April 2001. During 2001, the trial was overseeded a total of 5 times to guarantee the maximum possible recovery from seed
(Table 1).
Tabic 1. T reatnienl description, species, seeding rates and seeding times used for establishment of cool season grasses.

Summer-Fall 2001
Turf species
Kentucky bluegrass
Perennial ryegrass
Tall fescue
Fine fescue

Seed rate
Ib/1000lt2
o

P o a supina

10
10
10
2

Creeping bentgrass

2

Times
seeded
5
5
5
5
5
5

Total seed
lb/1000ft2
10
50
50
50
10
10

Traffic stress was applied with a GA-SWC traffic simulator (Carrow' et al. 2001). Each species received two levels of traffic. The traffic
simulator was operated with 2 or 4 passes of the simulator each Monday, Wednesday and Friday for a total of 6 and 12 passes per week.
Traffic simulation in 2001 started on April 20 and ended on May 15. Plots w'ere reseeded after this traffic period 2 times; traffic
simulation was then reinitiated 2 weeks later. Traffic simulation stopped on June 15 and the plots were reseeded again 1 time. The final
traffic period w'as from August 20 to October 26, 2001. The total number of passes in 2001 wtis 90 and 180. In 2002, traffic simulation
started August 19 and finished October 28 for a total of 10 weeks (60 and 120 passes). No additional seed w'as applied in 2002. No traffic
or seeding was done in 2003. Percent turf cover was evaluated several times during the traffic and recovery periods. A final evaluation
was performed on 29 May 2003.
This trial received 1 lb of Nitrogen on August. September and October of 2001. April. May, August and September of 2002 and April
and May of 2003 for a total of 9 lbs during the entire 25 months of traffic and recovery (20 April 2001 to 29 May 2003).
Results
Perennial ryegrass and Kentucky bluegrass consistently provided the most turf cover over the duration of the study (Table 2.). Supina
bluegrass provided the most turf cover in 2001 during the initial year of traffic treatment but as traffic continued in 2001 and 2002 Supina
bluegrass had less turf cover than Kentucky bluegrass, perennial ryegrass and tall fescue. Supina bluegrass prefers cool moist conditions
and high nitrogen. Summer heat and lower than desirable nitrogen may have contributed to decline in traffic tolerance in 2002 and 2003.
Tall Fescue is also a good option for sites that are under constant traffic. The opposite was observed for fine fescue. Constant seeding
helped fine fescue to maintain a moderate cover, but turf cover rapidly declined when seeding stopped.
Creeping bentgrass wears down quickly but also recovers quickly by spreading stolons. Ultimately creeping bentgrass had intermediate
to poor traffic tolerance (Table2).

71

Table 2. Percent turf cover at the end of each traffic and recovery period for 6 species of lurfgrass under 2 levels of traffic.

Recovery

Traffic
Jun 28-2001
Turf species
Kentucky bluegrass
Perennial ryegrass
Tall fescue
Fine fescue
Poet su p in a

Creeping bentgrass

Oct 26-2001

Oct 28-2002

Turf cover (
92
88
89
89
88
81
32
83
85
66
78
50

89
79
82
78
94
76

May 29-2003
90
92
80
31
72
62

LSI) IMi

15.36

3.03

10.97

11.81

Traffic intensity
2X
4X

n.d.
n.d.

89
81

79
57

81
63

1.75

6.33

6.83

LSD w

As expected, more traffic resulted in less turf cover. Traffic intensity had a significant effect. Doubling the amount of traffic, 2 passes
Vs. 4 passes reduced turf cover approximately from 80 to 65%.
Literature cited
Cairow, R.N. , R.R. Duncan, J.E. Worley and R.C. Shearman. 2001 Turfgrass traffic (soil compaction plus wear) simulator response of
Paspalum vaginatum and Cynodon spp. P. 253-258. In K .Carey (ed.) hit. Turf Soc. Research J. vol. 9.

72

1991 Corn Gluten Meal Crabgrass Control Study - Year 13-2003
Nick Christians and Luke Dant
Corn gluten meal (CGM) has been screened for efficacy as a natural product herbicide and fertilizer in turf on the same plot since 1991.
The study is being conducted at the Iowa State University Research Station north of Ames, 1A in an area o f ’Parade' Kentucky bluegrass.
The soil in this experimental area is a Nicollet (fine-loamy, mixed, mesic Aquic Hapludoll).
Individual experimental plots are 5 x 5 ft and there arc 5 treatments with 3 replications. The experimental design is a randomized
complete block. Corn gluten meal is applied once per year in April to the same plots at 0, 20, 40, 60, 80, 100, and 120 lbs/1000 ft2 (Table
1). Because corn gluten meal is 10% N, these rates are equivalent to 0, 2, 4, 6, 8, 10, and 12 lb N/1000 ft2. The CGM is applied each
year in a single carly-spring preemergence application using 'shaker dispensers’. The materials arc watcred-in with the irrigation system.
Supplemental irrigation is used to provide adequate moisture to maintain the grass in good growing condition. In 2003, applications were
made on April 25.
Turf quality was monitored from May through September (Table 1). It was assessed using a 9 to 1 scale with 9 = best. 6 = lowest
acceptable, and 1 = worst turf qual ity.
Weed populations were measured by either counting the number of plants or by estimating the percentage cover per individual plot.
Crabgrass infestations were determined by counting the number of plants per individual plot on August 4 and Sept. 17 (Table 2).
Dandelion populations were assessed by counting the number of plants per individual plot (Table 3). Clover populations were
determined by estimating the percentage area of each plot covered by clover (Table 4).
Data were analyzed with the Statistical Analysis System (SAS) and the Analysis of Variance (ANOVA) procedure. Effects of CGM on
turf quality and weed control were examined using Fisher’s Least Significant Difference (LSD) means comparison tests.

,, ,
Material

lbs CGM
IbsN
„
/1000 ft2 /1000 ft2 Ma>2 June 19 July 10 August 4 Sept 17
4
4
3
0
3
3
1 Untreated control
0
6
5
4
2 Corn gluten meal
2
5
20
5
4
7
40
6
6
6
5
3 Corn gluten meal
7
6
4 Corn gluten meal
6
7
6
60
5
8
8
7
8
7
5
5 Corn gluten meal
80
10
8
7
7
6
100
5
6 Corn gluten meal
7 Corn gluten meal
12
8
7
7
7
120
5
1.4
1.6
1.9
1.5
1.2
LSD.««
‘Turf quality was assessed using a 9 to 1 :scale with 9 = best, 6 = lowest acceptable, and 1 = worst turf quality.
NS = imeans are not significantly different at the 0.05 level.

Crabgrass counts1 in Kentucky bluegrass treated in the 1991 Corn Gluten Meal Weed Control Study.
lbs CGM
Material
August 4
Sept 17
/1000 ft2
0
14
16
1 Untreated control
4
6
2 Corn gluten meal
20
40
3 Corn gluten meal
0
0
0
4 Corn gluten meal
60
0
1
80
5
Corn gluten meal
0
2
1
100
6 Corn gluten meal
120
0
7
Corn gluten meal
0
NS
NS
____________________

These values represent the number of crabgrass plants per plot covered.
NS = means are not significantly different at the 0.05 level.

73

Table 3. Dandelion counts
lbs COM
May 21 June 19 July 10 Aug 4 Sept 17
/1000 ft2
0
54
26
31
31
33
Untreated control
14
14
21
17
20
20
Corn gluten meal
3
40
6
4
1
1
Corn gluten meal
2
60
4
1
0
Corn gluten meal
0
2
80
1
0
0
1
Corn gluten meal
100
0
1
1
1
3
Corn gluten meal
0
0
120
1
0
Corn gluten meal
0
16.7
14.4
27.9
NS
14.5
lsd «.«5
Material

1
2
3
4
5
6
7

These values represent the number of dandelion plants per plot.
NS = means are not significantly different at the 0.05 level.

Table 4. Percentage clover cover1in Kentucky bluegrass treated in the 1991 Corn Gluten Meal Weed Control Study.
lbs CGM
May 21 June 19 July 10 Aug 4 Sept 17
Material
nooo ft2

1
2
3
4
5
6
7

Untreated control
Corn gluten meal
Corn gluten meal
Corn gluten meal
Corn gluten meal
Corn gluten meal
Corn gluten meal
LSD,,05

0
20
40
60
80
100
120

38
23
22
27

6

5
2

31
8

5
6
4
8
2

NS
NS
’These values represent the area per plot covered by clover.
NS = means are not significantly different at the 0.05 level.

74

9

47
16
30

23
4
13

16
5

10
2

1

10

3

3
NS

5
NS

4
1
8.8

2
8
14

1995 Corn Gluten Meal Rate Weed Control Study - Year 9-2003
Nick Christians and Luke Dant
Com gluten meal (COM) is being screened for efficacy as a natural product herbicide in turf. This long-term study began in 1995 at the
Iowa State University Horticulture Research Station north of Ames, 1A. The experimental plot is in established 'Ram f Kentucky
blucgrass. The soil is a Nicollet (fine-loamy, mixed, niesic Aquic Hapludoll). Prior to treatment in 1995, the percentage broudlcaf weed
cover within the study perimeter exceeded 50%.
The experimental design is a randomized complete block design. Individual experimental plots are 10 x 10 ft with three replications.
Each year corn gluten meal is applied to the same plots at a yearly rate of 40 lb COM/1000 ft" (equivalent to 4 lb N/1000 lr) using four
different regimes of single and split applications for a total of five treatments (Table I). Four applications of 10 lb/1000 ft", split
applications of 20 lb/1000 ft2, an initial application of 30 lb plus a sequential of 10 lb/1000 ft2, and a single application of 40 lb/1000 ft2
are included with an untreated control.
Initial applications in 2003 were made on April 25 before crabgrass germination. The second application of treatment 2 was made on
June 23. The third application of treatment 2 and the second of treatments 3 and 4 were made on August 15. The final application of
treatment 2 was made on Sept 17.
The experimental plot was screened for phytotoxicity after each treatment. Turf quality data were taken monthly from spring greenup in
May through September. Visual quality was measured using a 9 to 1 scale with 9 = best and 6 = lowest acceptable, and 1 = worst quality
(Table I ).
Crabgrass plant populations per plot were recorded on August 4, and September 17 (Table 2).
Broadleaf data were taken from May through September. Dandelion and clover were the predominate broadleaf weed species within the
experimental plot. Dandelion populations were measured by counting the number of plants per plot (Table 3 ). Clover infestations were
estimated by determining the percentage area in each individual plot covered by clover (Table 4).
Data were analyzed with the Statistical Analysis System (SAS ) and the Analysis of Variance (ANOVA) procedure. Means comparisons
were made with Fisher's Least Significant Difference test (LSD).
Table 1.Turf quality1of Kentucky blucgrass treated with corn gluten meal for the 1995 Com Gluten Meal Rate Weed Control
Rate
Material
May 21 June 19 July 10 August 4 Sept 17
lb product/ 1000 ft2
2
4
4
1. Untreated control NA
5
5
6
7
3
2 . Corn gluten meal 10 lb 101b 10 lb 10 lb
6
6
6
7
7
3
3. Corn gluten meal 20 lb 20 lb
5
7
7
8
4. Corn gluten meal 30 lb 101b
6
3
7
7
7
6
5. Corn gluten meal 40 lb
3
1.2
1.6
NS
NS
NS
LSDo.os
1Turf quality was assessed using a 9 to 1 scale with 9 = best. 6 = lowest acceptable, and 1 = worst turf quality.

Table 2. Crabgrass counts' in Kentucky blucgrass treated with corn gluten meal in the 1995 Corn Gluten Meal Rate Weed Control
Study.
______________________________________________________________
Rate
Material
August 4 September 17
lb product/1000 ft2
4
10
1. Untreated control NA
3
4
2 . Corn gluten meal 10 lb 10 lb 101b 101b
1
3
3. Corn gluten meal 20 lb 20 lb
0
4. Corn gluten meal 30 lb 10 lb
3
2
1
5. Corn gluten meal 40 lb
NS
NS
LSD0.05

lrFhese values represent the number of crabgrass plants per plot.
NS = means are not significantly different at the 0.05 level.

75

Table 3. Dandelion counts1in Kentucky bluegrass treated with corn gluten meal in the 1995 Corn Gluten Meal Rate Weed Control
Study.
Rate
Material
June 19 July 10 Aug 4 Sept 17
lb product/1000 ft2 May 21
79
29
57
56
50
1. Cntreated control NA
14
19
2. Corn gluten meal 10 lb 10 lb 101b 10 lb
18
12
15
18
21
21
15
21
3. Corn gluten meal 20 lb 20 lb
19
16
12
12
16
4. Corn gluten meal 301b 101b
36
26
25
17
16
5. Corn gluten meal 401b
NS
NS
NS
NS
NS
LSD«.*
’These data represent the number of dandelion plants per plot.

Table 4. Percentage clover cover in Kentucky bluegrass treated with corn gluten meal in the 1995 Corn Gluten Meal Rate Weed
Control Study.
Rate
Material
June 19
May 21
July 10 Aug 4 Sept 17
lb product/1000 ft2
37
42
1. Untreated control NA
23
33
25
10
11
4
2. Corn gluten meal 10 lb 10 lb 101b 101b
8
8
7
4
5
5
3. Corn gluten meal 20 lb 20 lb
5
10
11
9
12
4. Corn gluten meal 30 lb 10 lb
15
14
3
7
9
5. Corn gluten meal 40 lb
8
NS
NS
NS
NS
NS
I.SIW

76

1999 Corn Gluten Meal/Urea Crabgrass Control Study - Year 5-2003
Nick Christians and Luke Dant
This study was initiated in 1999 to determine if the levels of annual grass and broadlcal* weed control provided by corn gluten meal
(CGM) treatments can be explained by the nitrogen response of treated bluegrass and not herbicidal activity of CGM. The study is being
conducted at the Iowa State University Research Station north of Ames. IA in an area o f ’Parade’ Kentucky bluegrass. The soil in this
experimental area is a Nicollet (line-loamy, mixed, mesic Aquic Hapludoll) with an organic matter content of 4.2%, a pH of 6.75, 17
ppm P. and 103 ppm K.
The experimental design is a randomized complete block with three replications. Individual experimental plots are 5 x 5 ft with five
treatments. Corn gluten meal and urea are applied yearly to the same plots at an annual rate of 4 lbs N/1000 ft' (Table 1). Treatments
included split applications of 2 lb N/1000 ft" and four applications of 1 lb N/1000 fr. The CGM and urea are applied using cardboard
containers as 'shaker dispensers’. The materials arc watered-in with the irrigation system. Supplemental irrigation is used to provide
adequate moisture to maintain the grass in good growing condition. In 2003, initial applications of all urea and CGM treatments were
made on April 26. Sequential applications of I lb N/1000 ft2 were made on June 23. August 15, and September 14. The second
applications of 2 lb N/1000 ft2 for urea and CGM (Treatment 3 and 5) were made on August 15.
Turf quality was monitored from May through September (Table 1). Visual turf quality was assessed using a 9 to 1 scale with 9 = best, 6
= lowest acceptable, and 1 = worst turf quality.
Crabgrass data represent the number of plants per individual plot. Crabgrass counts were made on August 4 and September 17 (Table 2).
Broadleaf weed populations were measured by either counting the number of plants or estimating the percentage cover per individual
plot. Data for dandelion and clover were taken beginning in May and ending in September. Dandelion infestations were determined by
counting the number of plants per individual plot. Clover populations were estimated by assessing the percentage area of each plot
covered by clover.
Data were analyzed with the Statistical Analysis System (SAS) and the Analysis of Variance (ANOVA) procedure. Effects of CGM and
urea on bluegrass quality and weed control were examined using Fisher’s Least Significant Difference (LSD) means comparison tests.

Table 1. Visual quality1of Kentucky bluegrass treated in the 1991 Coni Gluten Meal Weed Control StudyMaterial_________ Number of applications May 21 June 19 July 10 Aug 4 Sept 17
NA
4
4
4
5
3
1 Untreated control
4
4
5
2 Corn gluten meal
5
5
3
2
6
6
3
6
5
3 Corn gluten meal
4
5
4 Urea (46-0-0)
6
6
7
3
2
4
4
5 Urea (46-0-0)
6
5
LSD,,.«.«__________________________________0.64
NS
NS
NS
NS
'Visual quality was assessed using a 9 to I scale with 9 = best, 6 = lowest acceptable, and 1 = worst turf quality.
Initial applications of all treatments were made on April 21. Sequential applications of treatments 2 and 4 were made on July 7, July 27,
and September 5. The second applications of treatments 3 and 5 were made on July 27.
NS = means are not significantly different at the 0.05 level.

Table 2. Crabgrass counts1in Kentucky bluegrass treated in the 1999 Corn Gluten Meal/Urea Weed Control Study.
lbs N/1000 ft2 Number of applications August 4 September 17
Material
NA
NA
l Untreated control
5
3
4
4
2 Corn gluten meal
5
5
4
2
1
3
3 Corn gluten meal
4
4
14
4 Urea (46-0-0)
11
o
4
8
11
5 Urea (46-0-0)
NS
NS
LSD «
Tliesc values represent the number of crabgrass plants per plot covered.
NS = means are not significantly different at the 0.05 level.

77

Table 3. Dandelion counts' in Kentucky bluegrass treated in the 1999 Corn Gluten Mcal/Urea Weed Control Study.
Number of applications May 21 June 19 July 10 Aug 4 Sept 17
Material
18
21
21
NA
23
20
1 Untreated control
2 Corn gluten meal
4
21
23
18
21
19
9
14
13
15
16
16
3 Corn gluten meal
4
14
14
13
14
15
4 Urea (46-0-0)
2
21
19
18
18
18
5 Urea (46-0-0)
NS
NS
NS
NS
NS
LSD««
'These values represent the number of dandelion plants per plot.
NS = means are not significantly different at the 0.05 level.

Table 4. Percentage clover cover1in Kentucky bluegrass treated in the 1999 Corn Gluten Mcal/lJrea Weed Control Study.
Number of applications May 21 June 19 July 10 Aug 4 Sept 17
Material
2
17
NA
37
38
43
1 Untreated control
2 Corn gluten meal
4
22
17
28
20
6
2
2
15
23
15
9
3 Corn gluten meal
4
4
14
8
13
13
4 Urea (46-0-0)
2
14
9
18
15
10
5 Urea (46-0-0)
NS
NS
NS
NS
NS
LSDoos
'These values represent the area per plot covered by clover.
NS = means are not significantly different at the 0.05 level.

78

Field A ssessm ent o f W inter Injury on C reeping Bentgrass and Annual Biuegrass Putting Greens
GCSAA/IGCSA Cooperative Research Project - 2004 Report
D .D . M in n e r , F. V a Iv e r d e , D . L i a n d N . C h r i s t ia n s
J. A l is e i i

-

- Iow a

S t a t e U n iv e r s i t y

H y p e r io n F ie ld C lu b y P r e s id e n t IG C S A

J. N e w t o n

-

V e e n k e r M e m o r ia l G o l f C o u rse

Sec web site lor picture report hun://turf urass.horl.iasiate.edu/extension/
Introduction:
In 2001 John Newton, (CGCS) Veenker Memorial Golf Course, constructed a native soil green to develop cosponsored projects between
the GCSAA, IGCSA. and Iowa State University. The winter injury study is the first to be conducted at this facility. As each winter
unfolds we are faced with many questions: 1) should 1truck water to my greens. 2) should I invest in a cover. 3) should I topdress heavy,
4) should 1 remove the ice and when, and 5) did my snow mold control damage turf? Those that make it through the winter with no injury
gain faith that their strategy is working and those that loose grass are left in disbelief as to why this particular winter has caused them to
loose grass when it has not happened in the past. Our approach is to compare many scenarios for winter injury in a single year. This will
help superintendents make strategic action about decisions they face such as ice removal, trucking water, covers, etc. Decisions on
winter covers may be made early in the season with no ability to change strategy while others, like ice removal, may be made as the
season develops and are based on the superintendents experience. In fact, we actually have no idea when the grass actually dies during
the winter or spring. A unique part of our research strategy is to sample weekly during the winter to determine exactly when the grass
dies. Our main goal is to make Golf Course Superintendents better prepared to explain local winter turf injury to their golfing and
administrati ve clientele.
Rationale/description of problem:
Some level of winter injury occurs every year on putting greens and fairways in Iowa and other golf courses north of the transition zone.
When turf loss is substantial, the golf course superintendent is faced with explaining why the grass died and in many cases why it died on
their particular course and not on other courses near by. Many factors, such as direct low temperature, desiccation, ice cover, and soil
heaving, are considered responsible for winter kill (Beard, 1973). These factors alone or in combination may be responsible for winter
injury. Some research suggests that suffocation and toxic gas may be responsible for turf injury under ice (Freyman, 1967), and that ice
removal is. therefore, beneficial. On the contrary, there arc reports that no injuries to bentgrass were caused from ice cover for a period
from 60 to 150 days (Beard, 1965). However, it is a very common practice to remove the ice from the green and fairway (Kind, 1999)
even though there is no convincing research to justify this practice. Frost heaving (Kinbacher, 1956) and spring de-hardening under snow
cover (Bilbrough ct. al., 2000) have also been associated with winter damage to plants. In late winter and early spring, snow cover can
lead to de-hardening of the creeping bentgrass and annual biuegrass, and, thus, expose the grass to low temperature injury at this period
(Tompkins el. al., 2000). In 2001, Iowa experienced 90 days of continuous snow cover. Those superintendents who had applied snow
mold treatments were anticipating minimal turf injury because of the protective blanket of snow. Instead, it was one of the worst years
for injury to putting greens. Unfortunately, many research based explanations often contradict the obvious results that superintendents
are experiencing. Consequently superintendents and experts are often left groping for an explanation of why a particular winter condition
killed the grass. Most of the research to date evaluates a single type of winter injury and tries to determine if it is a contributing factor to
the dead grass. Our approach is to evaluate the relative amount of injury that is associated with various scenarios for winter conditions:
thus, providing the golf course superintendent with a reasonable idea of which type of winter condition has the greatest potential for turf
loss and, in turn, if it is worth the expense or effort to try and minimize the injury by taking action.
Objectives:
1.
2.
3.

To simulate and identify various types of winter conditions that result in turf injury under actual golf course conditions.
To determine the relative importance of winter injury on putting greens as it relates to snow cover, ice formation, desiccation,
crown hydration, and freeze/thaw cycles.
To determine if superintendents should allow winter to take its natural course of events or should they actively manage to
reduce winter injury by practices such as using protective covers and removing ice.

Materials/methods:
Ten possible winter scenarios: dry/open, wet, ice continuous, snow continuous, impermeable tarp + ice, ice removal, ice/melt freeze,
snow removal/melt freeze, evergreen turf cover, and evergreen turf cover with snow removed, were created on two separate Iowa putting
greens in 2004 (Table 1). One green was composed of ‘Pcnncross’ creeping bentgrass that was growing on a native soil at the Iowa State
University Veenker Memorial Golf Course and the other was 85% annual biuegrass and 15% creeping bentgrass growing on a USGAtype green at the Iowa State University Horticulture Research Station. The Veenker Memorial Green was mowed at 3.54 mm (0.14 in)
and the Horticulture Research Green was mowed at 6.35 mm (0.25 in). Two core samples per treatment, 3.5-in dia by 2-in deep, were
taken each week with a hammer drill and recovered in a growth chamber to determine when grass died during the winter. Alter one
month of recovery growth, the plugs were clipped at a 0.25 cm height and clippings were collected, dried, and weighed. Turf recovery in
the greenhouse (dry weight yield) was used to indicate the amount of winter injury. Recovering core samples and field plots were
visually evaluated for turf quality, 9=best, l=worst, and 6= lowest acceptable quality. The percent of living turf cover was rated for core

79

samples and field plots. Soil temperature was measured at 0.5 inches below the soil/thatch interface using thermocouples and a data
logger.
Snow and ice cover treatments began on January 6. Snow remained on the “continuous snow cover’ treatments for 71 days after January
6. Treatments designated for “ice cover” also began on January 6 and lasted for 67 consecutive days. Treatments #6, 7 and 8 received
“snow and ice removal” halfway through the season. Snow and ice were removed on February 23 giving these treatments 48 days of
continuous snow or ice cover.
The experimental design is a randomized complete block with three replications and data will be analyzed using the Statistical Analysis
System (SAS Institute Inc., 1996) and the Analysis of Variance (ANOVA) procedure
Table I. List of 2004 Winter treatments.
Simulated winter conditions
Winter
1.
Dry/Open
Dry
2.
Wet
Wet
Ice
Ice continuous
3.
Snow
4.
Snow
continuous
5.
Impermeable
ice
Cover + ice
6.
7.

Ice removal
Ice melt/freeze

8.
9.

Snow removal
Turfcover/Dry

10.

Turfcover/Snow

Winter - January, February
Spring - March

Spring_______ Description - Target and actual ()
Dry
No cover, no ice, no snow - turf subject to desiccation
Wet
Turf hydrated no surface ice
Extended ice cover for 90 (67) days
Ice
Snow
Extended snow cover 90 (71) days
White impermeable cover designed to prevent plant hydration and ice
Ice remove
encasement. 4 inches of ice over cover for 90 (67) days- ice started 16-04. Covers placed 12-1-03, removed 3-23-04.
Ice remove
Ice removed 60 (48) days after ice formation.
Ice
Natural melt/freeze cycle applied in the spring. Ice removed 60 (48)
Melt/freeze
Ice
days after ice formation.
Snow
Melt/lVeeze
Snow removed 60 (48) days after snow cover began.
Dry
Dry
Evergreen turf cover - ice/snow removed 60 (48) days after snow'
cover began. Covers placed 12-1-03, removed 3-23-04.
Evergreen turf cover - ice/snow present. Covers placed 12-1-03,
Snow
Snow
removed 3-23-04.
Snow - 4 inches of snow cover
Ice - 4 inches of ice cover

Results 2004:
During the winter of 2004, Ames, IA had 42 inches of snow cover with approximately 70 days of continuous snow cover from January
through early March. All snow occurred naturally in the research area and no ski resort snow was used in 2004. There were no reports
of winter injury from Golf Course Superintendents and, in general, soil moisture was not considered to be excessive or deficient. The
severe putting green desiccation that occurred during the winter of 2003 did not exist in 2004. Golf course superintendents in
Minneapolis and South Dakota experienced up to 90% turf loss on some putting greens even when covers were used. The type of cover
used could not be directly linked to turf injury. In Minnesota injury occurred on covered and non-covered greens with Poa annua
receiving severe injury and creeping bentgrass only slightly injured. In South Dakota creeping bentgrass was even severely damaged by
winter desiccation under covers.
Table 2 shows the recovery of both study areas following the winter of 2004.
Creeping bentgrass green - Veenker Golf Course
The creeping bentgrass on the native soil green at Veenker Golf Course did not experience any turf kill and all plots retained 100% turf
cover. However, coming out of winter turf color indicated that the dry desiccation treatment showed more winter injury than any of the
other treatments. Any type of cover (snow, ice, synthetic) improved the green appearance of the turf. Removing snow or removing ice
had little effect on winter recovery of the bentgrass. This is the first year that Green Jacket was used as an impermeable cover under the
ice layer. Creeping bentgrass under the impermeable cover + ice (trt. 5) had substantially belter appearance than the continuous ice
treatment (trt. 6).

Poa annua green - ISU Research Station
The results for 2004 were similar to those found in 2003 related to P o a an n u a winter injury. Treatments related with ice cover (tits.
3,6,7) showed the most loss of turf color and turf cover. By April 5, the impermeable cover + ice (trt. 5) had twice as much surviving
P o a a n n u a (69%) compared with the continuous ice treatment (trt. 4) ( 35%> cover). The Evergreen cover with or without snow removal
(trts. 9 and 10) resulted in the most turf survival on the P o a an n u a green. In 2003, snow cover substantially improved Poa annua
survival; however, the 2004 winter snow cover (trts. 4 and 8) had poor turf recovery. The natural snow cover in 2004 has some periods
of melt and freeze that provide about an inch of ice under the snow that may have contributed to some of the Poa annua injury in the
snow covered treatments.

80

Table 2. 2004 turf quality in field plots during spring green-up on a scale of 1-10, 10= completely green, 6=lowest acceptable quality,
l=bleachcd completely white. Poa annua survival rated as the percent of the plot area containing Poa annua cover.
Creeping bentgrass
P oa annua
ISU Research Station
Veenker Golf Course
Percent turf cover
Turf color 1-9, 9=best
Turf color 1-9, 9=best
April 5
April 5
March 3
April 5
March 3
Winter Treatments
March 3
1.0
5.3
4.0
5.0
61.7
53.3
1.
Dry
2.
6.7
6.7
69.4
65.0
4.3
5.0
Wet
6.7
65.0
35.6
4.0
1.0
2.0
Ice continuous
3.
4.7
65.6
36.7
5.3
6.7
4.3
4.
Snow
continuous
69.4
9.7
7.0
75.0
8.3
8.0
Impermeable
5.
Cover + ice
4.3
1.0
2.0
66.1
35.6
6.3
6.
Ice removal
1.0
56.7
10.0
6.7
4.3
2.0
7.
Ice melt/freeze
7.0
46.1
6.0
5.3
73.3
5.3
8.
Snow removal
86.1
82.2
7.7
9.0
8.7
9.0
Turfcover/Dry
9.
7.7
92.2
8.3
8.3
7.3
93.3
Turfcover/Snow
10.

Literature Cited:
Beard. J. B. 1965. Bentgrass (Agrostis spp.) varietal tolerance to ice cover injury. Agronomy Journal. 57:513.
Beard, J.B. 1973. Turfgrass: science and culture. Prentice-Hall, Inc., Englewood Cliffs, N.J.
Bilbrough C.J., J.M. Welker, and W.D. Bowman. 2000. Early spring nitrogen uptake by snow-covered plants: a comparison of arctic and
alpine plant function under the snowpack. Arctic. Antarctic, and Alpine Research. 32:404-411.
Decker A.M., and T.S. Ronningen. 1957. Heaving in forage stands and in bare ground. Agronomy Journal. 49:412-415.
Freyman, S. 1967. The nature of ice-sheet injury to forage plants. Ph.D. Thesis. University of British Columbia, pp.1-100.
Kinbacher, E. J. 1956. Resistance of seedlings to frost heaving injury. Agronomy Journal. 48:166-170.
Kind M. 1999. Turf talk-ice removal not always best. Golf Course Management, http://www.gcsaa.org/gcm/1999/dec99/12talk.html.
Stoeckeler J.H., and J.L. Thames. 1957. The lake stakes penetrometer for measuring depth of soil freezing. Forestry. 30:47-50.
Tompkins, D.K., J.B. Ross, and D.L. Moroz. 2000. Dehardening of annual bluegrass and creeping bentgrass during late winter and early
spring. Agronomy Journal.92:5-9.

81

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