1987

lowa
Tuifgrass
Research
Report

Cooperative Extension Service
15 Iowa State University
Ames, lowa 50011

FG-453 | June 1987

Introduction

The following research report is the seventh yearly publication of the results
of turfgrass research projects performed at Iowa State University.
The first
was published for the 1981 field day, which was held June 18, of that year.
The others were published in conjunction with the 1982, 1983, 1984, 1985, and
1986 field days.
The first cultivar and management studies at the field research area were
seeded in August 1979, and many of these investigations are now in their
eighth season.
The area has been expanded every year and by 1983 there were
4.2 acres of irrigated and approximately 3.0 acres of non-irrigated research
area.
Funding was obtained in 1983 to add 2.7 acres of irrigated research
plots to the existing site.
This construction was completed in the spring of
1985.
Several new studies were initiated on this area in the 1985 and 1986
seasons and a map showing the location of these studies can be found in this
report.
The expansion that has taken place since 1979 would not have been possible
without the cooperation of the Iowa Agriculture Experiment Station, the Iowa
Turfgrass Institute, the Iowa Golf Course Superintendent's Association, the
Iowa Professional Lawn Care Association, and the Iowa Turfgrass Producers and
Contractors (ITPAC) organization.
We would also like to acknowledge Kenneth Diesburg, Richard Moore, Young Joo,
Michael Burt, Zachary Reicher, Jim Walser, Dan Weidemeir, Jeff Ryan, Pat
Gradoville, Paul Johnson, Paul Dayton, and all the others employed at the field
research area in the past year for their efforts in building the program.
A special thanks goes to Betty Hempe for her work on typing this publication.

Edited by Nick Christians, associate professor, turfgrass science; Michael
Agnew, assistant professor, turfgrass extension; and Elaine Edwards, extension
communication specialist.

Table of Contents

ENVIRONMENTAL D A T A .......................................................1 - 2
TURFGRASS RESEARCH AREA M A P S ............................................ 3 - 5

SPECIES AND CULTIVAR TRIALS
Results of High- and Low-Maintenance Kentucky Bluegrass
Regional Cultivar Trials - 1986 ................................
Cedar Rapids High-Maintenance Kentucky Bluegrass Trials ..........

42""

Regional Perennial Ryegrass Cultivar Evaluation ..................

-IS"

Perennial Ryegrass Cultivar Evaluations ..........................

48

Fine Fescue Cultivar Trial

......................................

A9

Fine Fescue Management Study

....................................

J2ST'

Tall Fescue Management Study

....................................

-34

Bentgrass Management Study -1986 .................................

-26

FERTILIZER INVESTIGATIONS
Nitrogen X Potassium Study

......................................

-38

Evaluation of Different Granular Nitrogen Sources for
Fertilization of Kentucky Bluegrass Turf ......................

-30

..........

31

Evaluation of Liquid Fertilizer Programs on Three
Kentucky Bluegrass Cultivars ..................................

34

Summer Slow-Release Nitrogen Sources Comparison Study

HERBICIDE STUDIES
Preemergence Crabgrass Control Study - 1986 ......................

43

Postemergence Annual Grass Control Study - 1986 ..................

-45

Broadleaf Weed Control Study - 1986 ..............................

-48

Preeraergence Herbicide Timing Studies - 1986

.......... .........

Effects of Preemergence Herbicides on Rooting of
Kentucky Bluegrass - 1986 ....................
Sod Rooting Study - 1986

........................................

— 50

—52
J5M—

TURFGRASS DISEASE RESEARCH
Evaluation of Fungicides for Control of Dollar Spot
in Penncross Bentgrass - 1986 .....................................

-5-6"

Evaluation of Fungicides for Control of Bipolaris Leaf Spot
on Park Bluegrass - 1986 ........................................

57"“

STRESS STUDIES
Influence of Endophyte Infection of Perennial Ryegrass
on Tolerance to Drought Stress ..................................
Summer Dormancy Study of Kentucky Bluegrass Cultivar

..............

Comparison of Compaction Alleviation Products - 1986

..............

Cultivation Equipment Comparison Study

............................

63

Comparative Effectiveness of Insecticides Against
Annual White Grubs - 1986 ........................................

66

INSECT CONTROL

INTRODUCING
The Iowa State University Personnel
Affiliated with the Turfgrass Research Program

..................

COMPANIES AND ORGANIZATIONS that have made donations to the
Iowa State University Turfgrass Research Program . . .

69

70

RAINFALL 1966
i n ' + ' + ^ ' + ^ i o m r o n t o M N C N i o j N r - T - T - T - i - o o o o o

-ZOIWO)

1

AND DIAMOND SYMBOL
AMES— 5 DAY AVERAGES

TEMPERATURE 1986

Turfgrass Research Area Maps
Wildflower and
Native Grass
Establishment Study

tu
o
n

£
3

Common

National
Kentucky
Bluegrass
Trial
(Non-Irrigated)

CD

Vantage

Parade

Fall
Fertilization
Study

Premium

Baron

Parade

Rugby

Baron

Sod Production Study
Sod
Re-establishment
Buffalograss Management Study
Texoka Common Sharps

Tall Fescue
Management
Study

N & K Study
Phosphorus
Fertilization
Demonstration

Fine
Fescue
Management
Study

Parade
Preemergence Non-Irrigated j Irrigated
Herbicide
Perennial Ryegrass
Studies
Management Study
Bentgrass
Cultivar
Study
Premium
Sod
Blend

Sod Blend

P. Ryegrass
Cultivar Evaluations

Baron

Tu rf grass
Research
Plots

Park

Urease Inhibitor Trials

Tall Fescue
Park

Ram I

Creeping
i Bentgrass
1
1
1

________________ i
Penneagle Penncross
Fungicide
Trials

Emerald

Emerald
Fungicide
Trials

Penneagle

Kentucky
Bluegrass
Compaction
Study

Fine
Fescue
Cultivar
Trials

Perennial
Ryegrass
Cultivar
Evaluations
Tall FescueKentucky
Bluegrass
Seed Mixtures
Baron

i

I
----

Park

Sod Rooting Studies

Park
Kentucky Bluegrass

Penncross

N
Building
Regional Kentucky
Bluegrass Study
"Low Maintenance”

3

Map of Field Research Area
Established in the Fall of 1981
Parking Area

N
Regional Kentucky
Bluegrass Study
"High Maintenance”

Maintenance Building

FERTILIZER
STUDIES

155'

Road

Park
Kentucky
Bluegrass

Aeration Study
Studies

253’Total Area

4

39,215 ft2
0.90 Acres

(640 series heads)

_

Total Area = 2.7 acres

—— 60’— —

(650 series heads)

1984 Expansion of the Turfgrass Research Area
(690 series heads)

00

Ö

5

Results of High' and LoW'Maintenance
Kentucky Bluegrass Regional Cultivar Trials— 1986
N. E. Christians

In 1980, the United States Department of Agriculture (USDA) initiated a region­
al Kentucky bluegrass cultivar trial that is presently being conducted at most
of the northern agricultural experiment stations.
The test consists of 84
cultivars, with each cultivar replicated three times.
Three separate trials are underway at Iowa State University.
One 21s a highmaintenance study established in 1981 that receives 4 lb N/1000 ft /yr and is
irrigated as needed; another is a low-maintenance study established in 1980
that receives 1 lb N/1000 ft /yr in September and is not irrigated. The third
trial was established in 1985 and receives 4 lb N/1000 ft /yr but is not
irrigated.
The objective of the high-maintenance study is to investigate the
performance of the 84 cultivars under a cultural regime similar to that used on
irrigated home lawns in Iowa. The objective of the low-maintenance study is to
observe the performance of the 84 cultivars under conditions similar to those
that would be used in a park, school yard, or other low-maintenance areas. The
objective of the third study is to observe the response of the cultivars under
conditions similar to those found in a non-irrigated lawn that receives a
standard lawn care program.
Data collection for the third study will begin in
1987 and no data appears in this report.
The values listed under each month in tables 1 and 2 are the averages of
ratings made on three replicated plots for the high- and low-maintenance
studies. Yearly means of all the months in which data were taken are listed in
the last column.
The first cultivar received the highest average rating for
the entire 1985 season.
The cultivars are then listed in descending order of
average quality.
The least significant difference (LSD) value listed at the bottom of each
column is a statistical value that can be used to further evaluate the data.
For cultivars to be considered different from one another, their mean quality
ratings must exceed the LSD value.
For example, the yearly means for the
high-maintenance cultivars must exceed 0.6, the LSD for that column (Table 1).
RAM-1 with a mean reading of 7.5 performed better than Merit with a reading of
6.8.
However, the performance of RAM-1 was statistically the same as Glade
which had a yearly mean of 7.3.
RAM-1, Glade, Kimono, Adelphi, Cheri, WW Ag 478, and Midnight were the best of
the cultivars in the high-maintenance trial (Table 1). Most of these cultivars
have consistently performed well over the past few years and can be considered
to be among the best cultivars for Iowa conditions on high-maintenance sites.
It should be noted that most of the cultivars performed satisfactorily because
of the very mild weather conditions in 1986.

6

In past years, cultivars that performed well under high-maintenance conditions
did not do as well under low-maintenance conditions.
Conversely, many of the
poorer cultivars in high-maintenance areas were the best in the low-maintenance
study.
The 1986 season was so wet that this trend was not as apparent as in
past years.
The low-maintenance trial was not subjected to moisture stress at
any time during the summer.
K3-162, PSU-173, WW Ag *163, Plush, SH-2, and Cheri were the top rated cultivars
in the low-maintenance trial (Table 2).
Many cultivars that ranked in the
upper 25 positions in 1986 have been ranked much lower in dryer years.
In
choosing cultivars for low maintenance conditions, data from several years
should be considered.

7

Table 1.

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.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.

The 1986 quality ratings for the high-maintenance
bluegrass test established in the fall 1981.

regional Kentucky

Cultivar

May

June

July

Aug

Sept

Oct

Mean

RAM-1
Glade
Kimono
Adelphi
Cheri
WW Ag 478
Midnight
243
MLM-18011
Bonnieblue
Enmundi
FyIking
Rugby
Holiday
A20-6
N535
Mona
Escort
PSU-150
Merit
Shasta
Sydsport
SV-01617
Aspen
Mosa
A20
1-13
Barblue
Birka
PSU-173
Plush
Banff
America
A20-6A
Columbia
Merion
K3-178
K1-152
239
PSU-190
Baron
Parade
Trenton
Dormie
CEB VB 3965

7.0
7.3
6.3
7.0
7.0
6.7
6.0
7.7
7.3
7.0
5.7
6.7
7.0
6.7
6.3
7.0
7.0
7.0
6.7
6.7
6.7
6.7
6.3
6.7
6.7
6.7
6.0
7.7
6.7
6.7
6.7
7.0
7.0
5.0
6.3
6.7
6.3
5.7
6.3
6.7
6.7
6.7
6.0
6.0
7.3

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

6.7
5.7
7.7
7.3
7.3
7.3
7.0
6.7
6.0
7.0
7.0
6.3
6.3
6.7
7.7
6.7
6.0
6.3
7.0
6.7
6.3
7.0
5.3
6.7
6.3
7.7
8.0
6.7
6.7
6.7
7.3
6.0
7.0
7.0
6.3
7.0
6.3
7.0
6.3
6.3
6.0
6.0
6.7
7.0
6.3

8.3
8.3
6.7
7.3
6.7
7.7
8.7
7.7
7.0
7.0
7.3
6.7
6.3
6.7
6.0
7.0
6.3
7.3
7.0
7.0
6.7
6.7
7.3
5.7
6.7
6.0
6.0
5.7
6.3
5.7
6.3
5.3
6.0
6.3
7.0
7.0
7.0
6.0
6.3
6.3
7.0
7.0
6.0
6.0
6.0

8.3
8.0
8.0
7.0
7.7
7.7
8.0
7.3
7.7
8.0
7.7
7.3
7.7
7.7
7.0
7.3
7.7
7.3
7.7
7.3
7.7
7.0
7.7
7.3
7.3
6.3
6.3
7.0
7.0
7.Q
6.3
7.7
7.0
7.3
6.3
6.0
6.3
7.0
7.0
7.3
7.3
6.7
7.0
7.0
6.7

7.0
7.3
7.7
7.3
7.3
6.7
6.3
6.3
7.3
6.7
7.3
7.3
7.3
7.0
7.7
6.3
7.3
6.7
5.7
6.3
6.7
6.7
7.0
7.0
6.7
7.0
7.0
6.3
6.3
7.0
6.3
7.0
6.0
7.3
7.0
6.3
7.0
7.3
6.3
5.7
5.7
6.3
7.0
6.3
6.3

7.5
7.3
7.3
7.2
7.2
7.2
7.2
7.1
7.1
7.1
7.0
6.9
6.9
6.9
6.9
6.9
6.9
6.9
6.8
6.8
6.8
6.8
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
6.5
6.5
6.5
6.5
6.5
6.5
6.5

8

Table 1.

116.
1*7.
1*8.
119.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.
63.
61*.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
75.
76.
77.
78.
79.
80.
81.
82.
83.
81*.

The 1986 quality ratings for the high-■maintenance regional Kentucky
bluegrass test established in the fall 1981. (continued)

Cultivar

May

June

July

Aug

Sept

Oct

Mean

WW Ag 1*80
Harmony
Majestic
Bristol
SH-2
BA-61-91
P—11*1 (Mystic)
Admiral
K3-179
Geronimo
Charlotte
Bayside
Monopoly
Nugget
Touchdown
Welcome
WW Ag 1*63
Vanessa
Cello
A-34
Mer pp 300
NJ 735
Eclipse
Argyle
H-7
Enoble
S-21
Bono
Kenblue
Apart
Victa
225
Vantage
S.D. Common
Wabash
Piedmont
K3-162
Mer pp 1*3
Lovegreen

5.7
6.7
6.0
6.3
6.0
5.7
7.0
5.7
6.3
6.7
6.7
6.7
6.0
6.3
5.7
5.7
6.7
6.3
6.0
7.0
6.7
7.0
4.3
5.7
5.7
5.3
6.7
7.0
6.3
5.7
6.0
5.3
5.7
7.7
5.3
5.7
6.7
6.0
6.7

7.3
6.7
7.3
7.3
6.7
7.7
7.3
6.3
6.7
5.3
6.0
6.3
7.3
6.7
5.7
6.3
6.7
6.3
6.0
6.7
6.7
6.7
5.3
6.3
7.3
6.0
5.0
6.0
4.7
6.7
7.3
7.0
6.7
5.7
7.3
7.3
4.7
6.0
5.7

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

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

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

7.3
6.7
6.7
6.0
7.0
6.7
6.7
6.3
6.7
5.7
5.3
6.3
6.3
6.3
6.7
5.7
6.0
6.3
7.7
6.3
6.0
6.0
6.3
5.7
7.7
6.3
5.7
6.0
6.0
6.7
5.7
7.3
5.3
5.7
6.0
5.7
5.3
4.7
4.0

6.5
6.5
6.5
6.5
6.5
6.5
6.5
6.5
6.5
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
6.3
6.2
6.2
6.2
6.1
6.1
6.1
6.1
6.1
6.1
6.0
6.0
5.9
5.9
5.7
5.5
5.2

LSD

1.7

1.5

1.5

1.4

1.3

1.3

0.6

0.05

Quality based on a scale of 9 to 1; 9 = best quality, 6 = acceptable quality,
and 1 = poorest quality.

9

Table 2.

1.
2.
3.
11.
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.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.

The 1986 quality ratings for the low-maintenance
bluegrass test established in the fall 1980.

regional

Kentucky

Cultivar

May

June

July

Aug

Sept

Oct

Mean

K3-162
PSU-173
WW Ag 463
S-21
Plush
SH-2
Cheri
Baron
MLM-18011
CEB VB 3965
Midnight
S. D. Common
Glade
Wabash
PSU-150
Aspen
Kenblue
America
N535
Victa
Barblue
RAM-1
Holiday
243
Nugget
PSU-190
Trenton
Touchdown
Vanessa
Majestic
K3-178
Adelphi
FyIking
Mer pp 300
Mer pp 43
Enoble
Merion
Geronimo
Welcome
Cello
WW Ag 478
Piedmont
A20-6
BA-61-91
K1-152

6.3
6.0
4.3
6.0
3.3
4.7
5.0
4.0
4.0
4.3
3.7
5.7
5.7
6.0
5.3
3.7
5.3
4.3
3.7
4.3
3.7
2.7
4.3
3.7
3.3
4.0
4.0
4.3
4.7
4.3
4.7
3.7
4.0
4.0
3.3
3.7
5.0
4.3
3.0
4.0
3.7
4.7
4.3
3.0
3.3

5.0
6.3
6.7
4.7
7.0
6.3
6.3
6.3
7.3
5.7
6.3
4.7
6.0
5.3
5.3
6.0
4.3
6.0
6.0
6.3
5.7
7.0
6.3
5.7
6.3
6.3
6.7
5.3
6.3
6.3
5.3
6.0
5.7
5.3
5.0
5.7
5.0
5.3
5.7
5.0
5.3
5.3
6.0
6.0
5.7

6.0
5.3
5.3
5.0
6.0
5.0
5.7
5.3
4.7
6.0
5.3
5.0
5.0
4.7
4.3
5.0
5.3
5.0
5.0
5.0
5.3
5.3
4.3
4.7
4.7
4.7
5.0
5.0
4.7
5.0
4.7
4.7
5.3
4.0
5.0
4.3
5.3
5.0
5.0
5.7
4.7
4.0
4.7
5.0
4.3

6.7
5.7
5.0
6.0
5.7
5.0
4.7
5.0
5.3
5.3
5.7
6.0
4.0
4.7
5.3
5.0
6.3
5.3
5.3
4.3
5.3
5.0
4.0
5.3
5.3
5.0
4.3
4.3
4.3
4.0
4.3
4.7
5.0
5.0
5.3
5.7
4.3
4.3
5.7
4.3
4.7
4.3
4.3
4.7
4.7

6.3
5.7
6.3
6.3
5.7
5.7
5.7
6.0
5.3
4.7
5.7
5.3
5.7
4.3
5.0
5.7
6.0
5.0
5.7
6.0
5.7
6.0
5.3
5.7
5.0
5.7
5.0
5.7
5.0
5.3
5.0
5.3
5.0
5.3
5.7
4.7
5.0
5.3
4.7
5.0
5.0
5.0
4.3
5.0
5.0

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

6.3
5.8
5.8
5.7
5.5
5.5
5.4
5.4
5.4
5.4
5.4
5.4
5.3
5.3
5.3
5.3
5.3
5.3
5.3
5.3
5.3
5.2
5.2
5.1
5.1
5.1
5.1
5.1
5.1
5.1
5.1
5.0
5.0
5.0
5.0
5.0
5.0
4.9
4.9
4.9
4.9
4.9
4.9
4.9
4.9

10

Table 2.

46.
47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.
63.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
75.
76.
77.
78.
79.
80.
81.
82.
83.
84.

The 1986 quality ratings for the low-maintenance regional
bluegrass test established in the fall 1980.
(continued)

Kentucky

Cultivar

May

June

July

Aug

Sept

Oct

Mean

Kimono
Parade
Rugby
Mona
Bristol
NJ 735
225
Cheri
Enmundi
SV-01617
Banff
Bono
Argyle
Charlotte
A20-6A
Columbia
Lovegreen
Admiral
Eclipse
K3-179
Birka
Dormie
Vantage
Merit
A20
1-13
Shasta
Apart
A-34
Sydsport
Bayside
239
Harmony
Mosa
Bonnieblue
WW Ag 480
H-7
P 141 (Mystic)
Escort

4.7
5.7
4.7
3.3
3.0
3.0
4.3
4.0
3.3
3.0
3.0
5.7
5.3
3.3
4.3
3.3
3.0
3.7
4.3
3.3
5.0
4.3
5.7
3.7
3.7
3.7
3.7
4.0
4.7
3.0
5.7
3.7
4.3
3.3
3.3
2.7
3.7
3.3
4.7

5.7
5.3
6.0
6.0
5.7
5.7
5.7
6.3
6.0
6.0
5.7
5.0
5.0
6.0
6.0
5.7
5.3
5.3
5.7
5.3
5.3
5.0
4.7
5.7
5.3
7.0
5.7
5.0
4.7
5.7
5.3
6.0
4.7
5.7
5.3
6.0
6.0
6.3
6.3

5.0
3.3
4.0
4.7
4.3
4.7
4.0
4.3
4.0
4.3
4.3
3.3
4.7
4.7
4.3
4.0
4.7
4.3
3.3
4.3
3.7
4.0
3.3
4.0
5.0
4.0
3.7
4.7
4.3
4.7
4.0
4.0
3.3
4.3
5.0
4.7
4.3
4.7
4.3

5.0
4.0
4.0
4.3
4.0
4.0
4.3
4.0
4.3
4.3
4.0
4.0
5.0
4.7
3.3
4.3
4.3
4.0
4.3
4.0
4.3
3.7
4.0
4.7
4.3
3.3
3.3
4.3
4.0
4.0
3.3
3.7
3.7
4.0
3.7
3.3
3.7
3.3
3.0

4.3
5.0
4.3
5.3
5.7
5.7
4.3
4.0
5.3
4.7
6.0
4.3
4.0
4.3
4.3
5.7
5.0
4.0
5.0
5.0
4.3
5.3
4.7
4.7
4.3
4.0
5.3
4.7
4.3
4.7
4.0
4.7
4.7
4.7
4.7
5.3
3.7
4.3
3.7

4.3
5.7
6.0
5.3
6.0
6.0
6.0
5.7
5.3
5.7
5.3
5.7
4.3
5.3
5.7
5.3
5.7
6.7
5.7
6.0
5.0
5.3
5.3
5.0
5.0
5.7
6.0
5.0
5.3
5.3
5.0
5.0
5.0
5.0
5.0
4.3
5.0
4.7
4.7

4.8
4.8
4.8
4.8
4.8
4.8
4.8
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
4.6
4.6
4.6
4.6
4.6
4.6
4.6
4.6
4.6
4.6
4.6
4.5
4.5
4.5
4.5
4.4
4.4
4.4
4.4

LSD 0.05

1.5

1.3

1.8

1.5

1.7

1.4

0.8

Quality based on a scale of 9 to 1I; 9 = best quality, 6 = acceptable quality
and 1 = poorest quality.

11

Cedar Rapids High'Maintenance Kentucky Bluegrass Trials
M. A. Loan, P. A. Petersen, N. E. Christians, and M. L. Agnew

With the cooperation of Iowa State University, the first Kentucky bluegrass
trial was established in August 1985 at the turf farm of Blue Grass Enterprises
located northwest of Cedar Rapids, Iowa, on Blairs Ferry Road.
When Iowa State University received the 1980 USDA Regional Kentucky bluegrass
cultivar trials it was short two cultivars, SH-2 (Somerset) and Barblue, that
were replaced with Gnome and Georgetown.
In August 1985, with the help of Dr.
Michael Agnew, Iowa State University extension turfgrass specialist and Patty
Petersen, extension horticulture associate, Linn County, the 84 cultivars were
seeded into individual plots measuring 4 feet by 6 feet and replicated twice.
A starter fertilizer had been applied at 2 lb P^O^/IOOO ft (7-28-28) prior to
seeding and after seeding the plots were irrigated twice a day for three weeks.
An application of 1 lb N/1000 ft (20-10 10) was made in September.
After eight days, Kenblue and Cello had germinated in both replications. Others
to germinate quickly were Merit, Plush, Vantage, Welcome, Bayside, Vanessa,
Mona, Mystic, and Georgetown.
The plots made it through the 1985 winter just fine and the growing season ig
1986 was fairly normal.
The plots were maintained with 4 lb N/1000 ft
(20-10-10), mowed at 2 inches, and irrigated as needed.
One application of
broadleaf weed control was used in the spring to eliminate the winter annuals
established at the time of seeding.
During 1986, the turfgrass quality was
average to good with the highest in July and September, that was expected the
first full year after seeding.
There were no major disease or insect problems
in 1986.
The values listed under each month are the averages of the ratings on the two
replicated plots (Table 3). Yearly means of all the months in which data were
collected are listed in the last column.

Table 3.

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.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.

The 1986 quality ratings for the high-maintenance regional Kentucky
b l u e g r a s s t r i a l s established at Blue Grass Enterprises in Cedar
Rapids, Iowa, in the fall of 1985.

Cultivar

Apr

June

July

Aug

Sept

Enmundi
Plush
Bristol
Classic/225
WW Ag 463
K3-178
K3-179
Vanessa
Baron
A-20
239
Midnight
Wabash
PSU-150
Trenton
MLM-18011
Touchdown
Cello
PSU-190
Sydsport
Georgetown
WW Ag 480
Mosa
Birka
Majestic
K 1— 152
Victa
Parade
Geronimo
Gnome
RAM-1
America
Shasta
Bayside
Adelphi
Glade
Admiral
Harmony
Mona
Bono
H-7
K3-162
Welcome
BA-61-91
Columbia
Escort
Bonnieblue
NJ 735

5.5
6.0
4.5
6.0
6.0
5.5
5.5
5.0
5.0
5.5
6.0
4.5
4.5
5.5
5.5
4.5
5.0
6.0
5.5
4.5
5.5
4.0
5.3
5.0
5.0
5.0
4.0
5.0
5.0
4.5
4.0
3.5
4.0
4.5
4.0
3.5
4.5
5.0
4.8
5.0
5.0
5.0
5.5
3.5
4.5
4.5
5.0
4.5

7.2
6.4
6.6
6.3
6.7
6.7
6.4
6.5
6.9
6.3
5.8
6.6
6.4
6.8
6.1
6.5
6.0
6.7
6.0
6.5
5.6
6.2
6.3
7.0
5.2
6.5
6.8
6.2
6.2
6.1
6.3
6.1
6.0
6.3
5.9
6.4
6.1
6.3
6.1
6.8
5.3
6.6
6.0
5.9
4.8
5.5
5.4
5.9

8.8
7.8
8.5
8.3
7.8
7.8
8.0
8.5
8.0
8.0
7.8
8.5
8.8
7.5
7.3
7.8
8.3
8.3
8.3
7.8
8.0
7.5
8.3
8.0
7.5
7.8
8.3
7.5
7.8
8.0
7.5
8.0
7.8
7.8
7.8
8.3
7.3
8.0
7.7
7.8
7.3
7.5
8.0
7.8
7.3
6.8
7.8
7.8

7.5
7.3
7.0
6.8
6.8
6.8
6.8
6.8
6.5
6.3
6.8
6.5
7.3
6.5
6.0
6.5
6.5
6.0
6.8
6.8
6.5
7.3
5.8
6.3
6.8
6.0
6.3
6.0
6.5
6.3
6.5
6.5
6.3
6.5
6.8
6.3
6.8
6.3
6.3
6.3
6.3
6.0
5.8
6.5
7.0
5.5
5.5
6.0

8.3
8.3
9.0
8.0
7.8
8.3
8.3
8.0
8.3
8.5
8.0
8.3
7.3
7.8
9.0
8.5
8.0
6.8
7.0
8.0
8.0
8.5
7.8
7.0
8.8
8.0
7.8
8.3
7.5
8.0
8.3
8.5
8.5
7.5
8.0
8.0
7.8
6.8
7.5
6.3
8.0
6.8
6.5
8.0
8.0
8.3
7.8
7.3

13

Mean
7.5
7.2
7.1
7.1
7.0
7.0
7.0
7.0
6.9
6.9
6.9
6.9
6.9
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
6.6
6.6
6.6
6.6
6.5
6.5
6.5
6.5
6.5
6.5
6.5
6.5
6.5
6.4
6.4
6.4
6.4
6.3
6.3
6.1
6.3
6.3

Table 3-

49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.
63.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
75.
76
77.
78.
79.
80.
81.
82.
83.
84.

The 1986 quality ratings for the high-maintenance regional Kentucky
b l u e g r a s s t r i a l s established at Blue Grass Enterprises in Cedar
Rapids, Iowa, in the fall of 1985.
(continued)

Cultivar

Apr

June

July

Aug

Sept

Mean

Cheri
Rugby
WW Ag 478
Challenger/N535
A-34
Mystic/P-141
Holiday
A-20-6A
A-20-6
Eclipse
Kimono
Escort
Banff
Vantage
Merit
PSU-173
Mer pp 300
S-21
Nassau/243
Argyle
Enoble
Monoply
Apart
FyIking
Dormie
Aspen
Kenblue
SV-01617
CEB VB 3965
Piedmont
Lovegreen
Nugget
Merion
Mer pp 43
Charlotte
SD Cert

3.5
3.5
5.0
5.0
4.5
5.0
4.0
4.0
4.0
3.5
4.5
4.5
3.5
5.5
3.5
3.5
3.5
4.5
2.5
4.0
5.0
4.0
4.0
3.5
4.0
5.0
5.5
3.0
3.5
4.0
4.5
2.5
4.0
4.0
3.5
3.5

6.2
6.2
4.0
4.5
5.8
5.9
6.4
6.1
5.8
6.1
5.0
5.5
5.4
5.8
5.9
6.3
6.2
6.2
6.4
4.8
5.3
6.2
5.7
4.5
5.7
5.3
5.4
5.2
5.1
5.4
5.8
5.1
4.4
4.8
4.0
5.8

7.5
7.8
8.5
7.3
7.5
8.3
7.8
7.8
8.3
8.0
7.5
7.5
7.5
7.5
7.5
7.5
7.0
7.3
6.8
8.0
7.3
6.8
7.0
7.3
7.8
6.0
6.8
6.8
7.3
7.5
6.8
7.3
7.3
7.5
6.5
7.0

6.3
6.0
5.8
6.5
5.8
6.0
6.0
6.0
5.5
6.0
6.0
6.0
6.5
4.8
5.5
5.8
5.5
5.0
6.0
5.8
5.3
6.0
5.5
6.5
6.0
5.8
5.3
5.5
5.3
5.5
4.3
5.8
6.0
5.3
5.0
4.3

7.8
7.8
8.0
7.8
7.5
5.8
6.8
7.0
7.0
7.0
7.5
7.0
7.5
6.8
7.8
7.0
7.8
6.8
7.8
6.8
6.5
6.3
7.0
7.3
5.5
6.8
5.5
7.5
6.8
5.5
6.3
7.0
5.8
5.0
7.5
5.5

6.3
6.3
6.3
6.2
6.2
6.2
6.2
6.2
6.1
6.1
6.1
6.1
6.1
6.1
6.0
6.0
6.0
6.0
5.9
5.9
5.9
5.9
5.8
5.8
5.8
5.8
5.7
5.6
5.6
5.6
5.5
5.5
5.5
5.3
5.3
5.2

LSD 0.05

1.8

1.7

1.4

1.5

1.9

1.4

Quality based on a scale of 9 to 1; 9 = best quality, 6 = acceptable quality
and 1 = poorest quality.

14

Regional Perennial Ryegrass Cultivar Evaluation
K. L. Diesburg and N. E. Christians

This is the fourth year of data from the trial established in the fall of 1982
in conjunction with several identical trials across the country coordinated by
the USDA.
The purpose of the trial is to identify regional adaptation of the
48 perennial ryegrass cultivars.
Cultivars are evaluated each month of the
growing season for turf quality and disease.
p
The trial is maintained at a 2-inch mowing height with 3-4 lb N/1000 ft
through the growing season and is irrigated when needed to prevent drought.
Preemergence herbicide is applied once in the spring and broadleaf herbicide
is applied once in September to control weeds.
The summer of 1986 was cooler than normal. It is possible the usual ranking of
cultivars shifted against those that tolerate heat (Table 4).
The 48 cultivars can be divided into nine groups in decreasing level of turf
quality:
1.

Excellent throughout the growing season:
LP 702
SWRC-1

2.

Prelude

Yorktown II
Fiesta

M382

Excellent in spring to fair in fall:
Ranger
Blazer

5.

Tara

Good throughout the growing season:
Diplomat
Birdie

4.

Palmer

Slow spring green-up and excellent thereafter:
Manhattan II
Repelí

3.

HE 168
Citation II

Pennant

WWE 19

Fair in spring to excellent in fall:
Gator

HE 178

15

Elka

6.

Fair in spring to good in fall:
Premier
Cigil

7.

HR 1

Good in spring to fair in fall:
All Star
Omega

8.

Manhattan
Pennfine

LP 792

Fair throughout the growing season:
Citation
Delray
Cupido
Birdie II
Regal
NK79309

Cockade
Cowbow
Dasher
LP 210
NK 79307

Acclaim
Barry
NK80389
Ovation
Derby

9.

Crown

Poor throughout the growing season:
Pippin

Linn

Table 4 . Turf quality3 of perennial ryegrass cultivars in 1986.

Cultivar

Apr

May

Jun

Ratings3
Aug
Jul

Sep

Oct

Mean

LP702
SWRC-1
HE 168
Palmer
Citation II
(282)
Ranger
Blazer
Manhattan II
Repell (GT-II)
Pennant
Tara (BT-1)
Diplomat
Prelude
Yorktown II
HE 178
Fiesta
WWE 19
Gator
Birdie
Premier

5.3
4.3
5.7
4.3

7.0
7.3
7.7
7.3

8.3
8.7
8.3
8.0

9.0
9.0
8.3
8.3

9.0
8.7
8.3
8.7

9.0
9.0
9.0
8.3

8.3
8.0
7.3
8.7

8.0
7.9
7.8
7.7

5.0
5.7
5.3
4.0
3.7
4.7
3.7
5.7
3.7
4.7
3.7
4.0
5.7
4.3
4.3
4.3

7.3
7.7
7.3
6.7
6.3
7.3
6.0
7.3
5.7
7.0
6.3
7.0
7.7
5.7
6.7
6.3

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

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

8.7
7.3
8.0
8.0
8.3
8.3
8.3
7.3
8.0
8.0
7.3
7.0
7.0
7.3
7.3
7.3

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

7.0
6.7
6.7
7.7
8.0
6.7
7.7
7.3
7.3
7.0
7.3
6.7
6.7
7.7
6.7
7.0

7.7
7.5
7.5
7.5
7.5
7.4
7.3
7.2
7.0
7.0
7.0
7.0
7.0
7.0
7.0
6.9

16

Table 4.

Turf quality3 of perennial ryegrass cultivars in 1986.

(continued)

Cultivar

Apr

May

Jun

Ratings3
Jul
Aug

Sep

Oct

Mean

M 382
All Star
(IA 728)
Elka
Cigil
Omega
HR-1
Acclaim
Manhattan
Barry
Crown
LP 792
Pennfine
Ovation
(LP 736)
NK80389
Cockade
Cowboy (2EE)1
Derby
Dasher
LP 210
Citation
Birdie II
(2 Ed)
Delray
NK79307
Cupido
NK79309
Regal
Pippin
Linn

3.7

6.7

8.0

7.7

7.3

7.7

7.3

6.9

3.7
4.0
4.7
4.7
3.3
4.3
5.0
3.3
3.7
4.7
4.0

6.7
6.3
5.7
6.7
6.3
6.3
8.0
6.3
6.7
6.7
6.7

8.0
7.7
7.3
7.0
7.3
7.3
7.3
7.7
7.3
7.0
7.7

8.3
6.7
7.0
8.0
8.0
7.3
6.7
7.3
7.0
6.3
8.0

7.0
7.0
7.3
6.7
7.7
6.7
6.0
7.0
6.7
7.0
7.0

8.0
8.7
8.3
7.7
8.0
7.7
7.3
8.3
8.0
8.0
7.0

6.3
7.7
7.3
6.7
6.7
7.0
6.3
6.3
7.0
6.3
6.0

6.9
6.9
6.9
6.8
6.8
6.7
6.7
6.6
6.6
6.6
6.6

4.0
4.0
4.3
3.7
3.7
3.7
4.0
3.7

6.3
6.3
6.3
6.0
6.3
5.3
6.3
6.3

7.3
7.7
6.7
7.3
7.3
7.3
6.7
7.0

7.0
6.7
6.3
7.7
7.0
7.7
7.0
6.3

6.3
5.7
6.7
6.3
6.7
7.0
6.3
6.3

7.7
7.7
8.0
7.3
7.0
7.7
7.3
6.0

7.0
7.3
6.3
6.3
7.0
5.7
6.0
6.7

6.5
6.5
6.4
6.4
6.4
6.3
6.2
6.0

2.7
3.7
4.3
3.7
4.0
4.0
2.7
3.0

5.0
6.0
6.0
5.3
5.3
5.3
3.7
3.0

7.0
7.3
7.3
7.3
7.3
7.0
6.0
4.7

7.7
6.7
6.7
7.3
7.0
6.7
5.3
4.3

6.3
6.0
5.0
5.0
6.3
5.0
4.0
3.3

7.0
6.7
6.7
6.3
5.7
6.3
6.0
4.0

6.3
5.7
6.3
6.7
5.0
6.0
5.3
4.0

6.0
6.0
6.0
6.0
5.8
5.8
4.7
3.8

Experiment
Mean

4.2

6.4

7.5

7.5

7.0

7.7

6.8

6.7

LSD

1.7

2.1

1.1

1.5

1.6

1.2

1.1

1.0

a

0.05

Quality based on a scale of 9 to
quality, and 1 = poorest quality.

17

1;

9 = best quality,

6 = acceptable

Perennial Ryegrass Cultivar Evaluations
N. E. Christians

The 22 perennial ryegrass cultivars in this trial were among the first plots to
be established after the renovation of the field research area in 1979.
The
study has been maintained siqpe that time at a 2-inch mowing height and is
fertilized with 4 lb N/1000 ft /yr. The area receives no fungicide or insecti­
cide applications.
Belle, Fiesta, and Derby received the highest overall quality ratings in 1986.
The first 12 cultivars received satisfactory ratings (Table 5).
NK-100 and
Linn received the lowest ratings in 1985.

Table 5.

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.

The 1986 quality ratings for 22 perennial ryegrass cultivars estab­
lished in 1979.

Cultivar

May

June

Quality Ratings
July
Aug
Sept

Oct

Mean

Belle
Fiesta
Derby
Elka
Yorktown
Blyes
Loretta
Diplomat
K5-88
Manhattan
Delray
Caravelle
Citation
K5-94
Pennfine
Med. North
Regal
J 186 R24D
Goalie
NK-200
NK-100
Linn

8.3
6.7
7.0
7.3
6.7
6.3
6.3
6.0
6.3
6.3
6.0
6.3
5.3
5.3
6.3
5.0
5.7
5.0
5.3
5.7
5.0
4.3

7.7
7.0
8.0
6.0
7.7
7.0
7.3
7.3
6.0
6.0
6.7
7.3
5.7
6.3
7.7
7.3
6.0
6.3
5.3
5.3
5.0
3.7

8.3
8.0
7.7
7.7
7.3
7.7
5.3
7.3
6.3
6.7
5.7
5.0
6.0
5.3
5.3
6.0
5.3
5.0
4.7
4.7
4.0
3.7

6.3
6.7
7.0
8.0
6.3
6.0
7.7
5.7
7.3
7.0
6.0
5.3
6.7
6.0
5.3
4.3
4.0
5.0
4.7
4.7
4.0
3.0

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

7.0
7.0
5.7
6.3
7.0
6.7
7.3
7.3
6.0
6.3
5.7
5.3
5.3
5.3
4.7
5.7
4.7
5.0
5.0
4.7
4.0
4.7

7.5
7.1
7.0
6.9
6.9
6.8
6.8
6.8
6.6
6.6
6.2
6.0
5.9
5.9
5.9
5.7
5.3
5.2
5.2
5.1
4.6
4.1

LSD

1.6

1.5

2.0

2.1

1.3

1.4

1.0

0.05

Quality based on a scale of 9 to 1 ; 9 = best quality, 6 = acceptable quality
and 1 = poorest quality.

18

Fine Fescue Cultivar Trial
K. L. Diesburg and N. E. Christians

This is the fourth year of data from the trial established in the fall of 1982.
The purpose of the trial is to identify regional adaptation of the 32 fine
fescue cultivars and blends tested.
Cultivars are evaluated each month of the
growing season for turf quality and disease.
2
The trial is maintained at a 2-inch mowing height with 3-1! lb N/1000 ft
through the growing season and is irrigated when needed to prevent drought.
Preemergence herbicide is applied once in the spring and broadleaf herbicide
is applied once in September to control weeds.
Disease is usually a problem at this site during the summer. At that time, the
necessary conditions of hot days, warm nights, high humidity, and moist soil
from irrigation combine, allowing pathogens to thrive. The summer of 1986 was
moist and cool allowing pathogens to persist but not kill any turf. The ratings
of most cultivars were, therefore, lower than usual throughout the season due
to a brown understory in their canopy.
This is reflected in the experiment
mean for each month in table 6, that is lower in almost every case compared to
1985 when neither disease nor drought was a problem.
The performance of the
cultivars as a group was consistent across months except in April and October
when they were close to winter dormancy.
Many of the cultivars have allowed the encroachment of Kentucky bluegrass since
1982.
Waldina, Tournament, Pennlawn, NK79190, NK79191, 1^803*15, NK80347,
1^803*18, and Duar had 20-100 percent Kentucky bluegrass in two or three of
their replications. This implies either lack of competitiveness to or compati­
bility with Kentucky bluegrass.
The general effect of the bluegrass presence
is improved turf quality.
The 32 cultivars can be divided into eight groups in decreasing level of turf
quality:
1.

Excellent throughout the growing season:
Jamestown

2.

Good in spring to excellent in fall:
FOF-WC

Scaldis

Waldina

Excellent in spring to good in fall:
Shadow

nksos^

Checker

19

Aurora

4

Good throughout the growing season:
Dawson

5.

Atlanta

NK79190

NK80348

Fair throughout the growing season:
Banner
Dawson/Pennlawn
Banner/Checker

8.

Tournament

Ensylva

Good in spring to fair in fall:
NK79189

7.

Scaldis/Atlanta

Sensitive to environmental fluctuations:
Biljart

6.

Barfalla

Agram
Fortress
Wintergreen

Pennlawn
Koket

NK80346
NK79191

Fair to poor throughout the growing season:
NK80347

Ruby

Duar

20

Highlight

Table 6. Turf quality ratings of fine fescue cultivars and blends.

BlueGrass

Turf quality3
Apr

May

Jun

Jul

Aug

Sep

Oct

Mean

6.3
7.3
6.3
6.0
7.0
6.0
5.7
6.3
5.0
5.7
5.7
7.3
6.7
6.0
5.7
7.0
5.3
4.7
5.3
5.0
4.7
5.7
6.0
5.0
6.3
6.0
5.0
6.3
4.3
5.7
6.3
2.7

8.3
7.7
7.0
8.3
7.7
8.7
8.7
8.3
8.0
8.0
7.7
7.7
8.0
8.3
8.3
7.0
7.0
7.0
7.0
7.7
7.7
7.3
7.0
7.0
7.3
8.0
7.7
8.0
7.0
7.3
4.0
6.0

8.3
7.0
8.3
8.0
7.3
8.0
8.0
7.0
8.3
8.3
7.7
7.3
8.3
8.0
7.3
7.7
6.7
8.7
6.7
7.7
6.7
7.3
6.0
6.0
6.7
7.3
6.3
6.7
7.7
7.3
7.3
6.3

8.0
8.0
7.7
7.7
8.0
8.3
8.0
8.0
7.7
8.0
7.0
7.3
8.0
7.0
7.3
7.3
7.3
6.3
7.0
7.0
6.7
7.0
6.3
7.0
7.0
7.0
7.0
6.7
6.0
5.0
6.7
6.3

8.3
8.3
9.0
8.0
8.3
7.7
7.7
7.0
7.3
7.0
8.3
7.0
8.0
6.7
7.3
6.0
7.0
7.0
7.0
6.0
6.3
7.0
6.7
7.3
7.0
6.0
6.0
5.0
5.7
5.7
7.0
7.0

8.3
8.7
8.3
8.3
7.7
7.7
8.0
8.0
8.3
7.3
8.3
8.0
7.0
8.0
7.0
6.0
7.0
7.3
7.0
7.3
7.3
7.0
7.0
7.0
6.0
5.0
6.7
6.0
5.7
7.0
6.0
5.3

6.7
6.7
7.0
7.7
7.0
6.3
5.7
6.7
6.7
7.0
5.0
6.0
3.7
4.7
6.0
7.0
6.3
5.7
5.3
4.3
5.7
3.7
5.0
4.7
4.0
4.3
5.0
4.0
6.0
4.0
3.7
3.3

7.8
7.7
7.7
7.7
7.6
7.5
7.4
7.3
7.3
7.3
7.1
7.1
7.1
7.0
7.0
6.9
6.7
6.7
6.5
6.4
6.4
6.4
6.3
6.3
6.3
6.2
6.2
6.1
6.0
6.0
5.9
5.3

30.0
43.3
34.7
35.0
35.0
6.7
2.3
0.3
0.0
23.3
30.0
0.7
96.7
21.7
3.7
63.3
3.3
23.3
5.0
6.7
13.3
16.0
31.7
50.0
40.0
61.7
0.0
40.0
26.7
61.7
70.0
13.3

Experiment Mean

5.7

7.5

7.4

7.2

7.1

7.2

5.5

6.8

27.8

LSD =0.05

1.7

0.9

1.5

1.5

1.2

1.3

1.5

0.7

47.9

Cultivar
Jamestown
Waldina
Aurora
FOF-WC
Scaldis
Shadow
Checker
Atlanta
Dawson
Biljart
Ensylva
Barfalla
NK80345
NK79189
Scaldis/Atlanta
Tournament
Banner
Dawson/Pennlawn
Koket
Wintergreen
Agram
NK80346
Fortress
Pennlawn
NK79191
NK80348
Banner/Checker
NK79190
Highlight
NK80347
Duar
Ruby

k

Cb
HF
HF
SF
HF
C
c
C
CR
HF
CR
C
CR
CR
HF
CF
C
C
C
CR
CR
CR
CR
CR
CR
C
CR
HF
CR

%

Quality based on a scale of 9 to 1: 9 = best quality, 6 = acceptable
quality, and 1 = poorest quality.
Chewings (C), creeping red (CR), sheep (S), or hard (H) fescue.

21

Fine Fescue Management Study
N. E. Christians

The fine fescue management study includes the following cultivars:
1.
2.
3.
5.

6.
7.
8.
9.
10.

Pennlawn Red Fescue
Scaldis Hard Fescue
Ruby Red Fescue
Atlanta Chewings Fescue
K5-29 Red Fescue

Dawson Red Fescue
Reliant Hard Fescue
Ensylva Red Fescue
Highlight Chewings Fescue
Jamestown Chewings Fescue

Each cultivar is maintained at two mowing heights: 1 and 2 inche^.
Each plot
is divided into two fertilizer treatments: 1 and 3 lb N/1000 ft , applied as
IBDU. Each plot is irrigated as needed.
The study was established on Septem­
ber 8, 1979.
The quality ratings in table 7 are the means of monthly ratings taken on repli­
cated plots from May to October.
As in 1985, Reliant and Scaldis Hard Fescue
were the only grasses of the 10 in this study to maintain a satisfactory
overall quality mean for the entire season.
At the 2-inch mowing height, only Reliant maintained a satisfactory quality
rating of 6 or better at the 1 lb N/1000 ft /yr fertility t^ate.
Scaldis was
very close to an acceptable rating.
At the 3 lb N/1000 ft /yr rate Reliant,
Scaldis, and Atlanta maintained a satisfactory quality.
At the 1-inch mowing height* none of the grasses maintained a satisfactory
quality at the 1 lb N/1000 ft /yr rate. Reliant, Scaldis, and Atlanta were the
best cultivars at the 3 lb N/1000 ft /yr rate. This study has been in progress
for seven seasons.
The fact that any of these grasses have maintained an
acceptable cover at a 1-inch mowing height for that length of time is
surprising.
The cultivars listed as acceptable have consistently performed well during the
study.
There is a large difference between poorly rated cultivars and accept­
able cultivars.
The choice of fine fescue cultivars for this region should be
made carefully, as many are not well adapted to Iowa conditions.

22

Table 7.

The effects of mowing height and nitrogen fertilizer on the quality
of 10 fine fescues.
Mowing Height
2 inch
1 inch
N Rate
N Rate
1 lb
3 lb
1 lba
3 lb

Overall
Mean

1.

Pennlawn Red Fescue

4.1b ,c

5.6

4.1

5.7

4.9

2.

Scaldis Hard Fescue

5.5

7.2

5.8

7.3

6.5

3.

Ruby Red Fescue

3.1

4.1

3.3

4.5

3.8

4.

Atlanta Chewings Fescue

5.5

7.2

5.3

6.7

6.2

5.

K5-29 Red Fescue

3.5

4.8

3.5

4.6

4.1

6.

Dawson Red Fescue

3.5

4.9

3.9

5.0

4.3

7.

Reliant Hard Fescue

5.8

7.7

6.2

7.5

6.8

8.

Ensylva Red Fescue

3.9

4.9

3.5

5.3

4.4

9.

Highlight Chewings Fescue

2.9

3.5

3.0

3.5

3.2

10.

Jamestown Chewings Fescue

4.3

6.1

4.4

5.9

5.2

a

N rates are in lb N/1000 ft^/yr.. The N source is IBDU.
Values are the means of monthly observations from May to October.
Quality based on a scale of 9 to
quality; and 1 = poorest quality.

23

1; 9 = best

quality,

6 = acceptable

Tall Fescue Management Study
K. L. Diesburg and N. E. Christians

This is a report of the third year of data from the experiment. It is designed
to compare the response of Falcon, Houndog, Kentucky 31, Mustang, and Rebel
tall fescue at 0, 2, and 4 lb N/1000 ftk /vr and cutting heights of 2 and 3
inches. One poundof N was applied once during each month of May and September
for the 2-lb treatment and during April, May, August, and September for the
4-lb treatment.
In the strip-split plot arrangement all six combinations of
the two management factors are placed in a 2 feet by 3 feet block within each
cultivar with the five cultivars replicated three times.
A single application
each of DCPA in the spring and a phenoxy herbicide in the fall is sufficient to
control weeds.
The 2-inch cut resulted in higher quality turf with all cultivars except
Kentucky 31 where turf quality was similar between its two cutting managements
(Table 8). The two increments in applied N, 0-2 lb and 2-4 lb, caused similar
increases in turf quality for all cultivars except Houndog which responded less
to the 0-2 lb increment.
Cultivar means and averages show that the four turf-type cultivars were similar
to each other and superior to Kentucky 31 over all managements.
There were
four occasions in the high cut management, however, when Kentucky 31 had turf
quality comparable to the others; April and September at all fertility levels,
July at the low fertility level, and August at the high fertility level.
Improvement of turf quality at higher fertility levels for all cultivars was
due primarily to better color resulting from higher chlorophyll content and
less yellowing from disease. In addition, the turf-type cultivars showed finer
leaf texture and higher leaf density at the 2-inch cutting height. Kentucky 31
responded with finer leaves, but leaf density decreased with a net smaller
improvement of turf quality.
A 3- to 3 1/2-inch cutting height is traditionally recommended for Kentucky 31
tall fescue turf.
This cultivar was released in 1943 for forage and land
reclamation purposes.
It is not as well adapted for turf as are the turf-type
cultivars.
The initial response of all perennial grasses to lower clipping
height is more diminutive growth giving a finer texture. Only those adapted to
the stress of close clipping will persist over many years.
Data from future
years will allow assessment of the persistence level of each cultivar.

24

Table 8.

Cultivar

Turf quality of tall fescue
three fertility levels.
Clip
Hgt
inch

cultivars at

N lb/
Apr

May

Jun

two clipping heights and

a
Ratings'
Jul
Aug

Sep

Oct

Mean

Mustang

2
0
2
2
4
2
0
3
2
3
4
3
Average

4.3
4.0
7.0
3.3
4.0
6.3
4.8

5.0
4.3
7.3
3.7
5.0
7.7
5.5

4.3
7.3
8.7
4.0
7.0
8.3
6.1

5.0
7.3
7.7
3.7
5.7
7.0
6.1

5.0
6.0
8.3
4.7
5.0
6.3
5.6

5.7
6.3
7.7
4.3
5.0
6.0
5.8

6.3
6.7
8.3
5.3
5.7
7.7
7.2

5.1
6.0
7.9
4.1
5.3
7.0
5.9

Houndog

0
2
2
2
2
4
0
3
2
3
4
3
Average

5.0
5.7
6.3
3.7
5.3
5.3
5.2

4.7
5.7
7.0
4.0
5.3
6.7
5.6

4.7
7.0
7.7
3.7
6.0
7.3
6.1

4.7
7.3
7.7
3.7
6.0
7.0
6.1

5.0
6.0
8.0
3.7
5.0
6.0
5.6

5.7
6.7
8.0
4.3
5.0
6.0
5.9

7.0
7.0
8.3
6.0
5.7
7.3
6.9

5.2
6.5
7.6
4.1
5.5
6.5
5.9

Rebel

2
0
2
2
4
2
0
3
2
3
4
3
Average

5.3
5.0
6.3
4.7
3.7
5.7
5.1

5.0
5.0
7.3
4.7
4.7
6.7
5.6

3.7
7.0
8.3
3.7
6.3
7.3
6.1

5.0
6.7
8.0
4.0
6.0
7.0
6.1

4.7
5.3
8.0
4.3
5.0
6.0
5.6

5.3
6.3
7.7
4.3
5.0
6.0
5.8

7.0
7.0
9.0
6.0
6.0
8.0
7.2

5.1
6.0
7.8
4.5
5.2
6.7
5.9

Falcon

0
2
2
2
4
2
0
3
2
3
4
3 ■
Average

4.3
4.7
5.7
4.3
5.0
6.7
5.1

4.3
4.7
7.3
4.3
4.7
7.3
5.4

4.0
6.7
8.3
4.0
6.3
7.7
6.2

5.0
6.3
7.7
4.0
5.7
6.7
5.9

4.7
6.0
8.0
4.3
5.0
6.3
5.7

5.7
6.3
7.7
4.7
5.0
6.0
5.9

6.3
7.0
8.7
5.3
5.7
8.0
6.8

4.9
6.0
7.6
4.4
5.3
7.0
5.9

Kentucky
31

2
0
2
2
4
2
0
3
2
3
4
3
Average

4.0
4.3
6.3
3.0
5.0
7.0
4.9

3.0
3.7
6.0
2.7
4.0
6.3
4.3

3.3
5.0
6.3
3.3
5.0
6.3
4.9

4.3
6.0
'6.7
4.0
5.0
6.3
5.4

3.7
4.7
6.7
3.3
4.0
6.0
4.7

4.0
5.0
5.7
4.0
4.7
5.7
4.8

5.3
5.7
7.7
4.3
5.0
7.0
5.8

4.0
4.9
6.5
3.5
4.7
6.4
5.0

0.6
1.3

0.6
0.9

0.9
0.7

0.5
0.7

0.8
0.7

0.3
0.6

0.7
0.6

0.4
0.4

LSD cultivar averages
LSD managements
a

Quality based on a scale of 9 to 1 ; 9 = best quality, 6 = acceptable quality
and 1 = poorest quality.

25

Bentgrass Management Study— 1986
N. E. Christians

The bentgrass management study was established
includes the following species and cultivars:
Species
1.
2.
3.
4.
5.
6.

Agrostis
Agrostis
Agrostis
Agrostis
Agrostis
Agrostis

in the

fall of

1980.

It

Cultivar

stolonifera Creeping Bentgrass
canina Velvet Bentgrass
stolonifera Creeping Bentgrass
stolonifera Creeping Bentgrass
stolonifera Creeping Bentgrass
stolonifera Creeping Bentgrass

Emerald
Kingstown
Penncross
Penneagle
Prominent
Seaside

Each cultivar^ planting is split into three fertility levels: 0.5, 0.8, and 1.2
lb N/1000 ft /growing month,
¿’his results in a total N application rate of
3.5, 5.6, and 8.4 lb N/1000 ft /year.
The area was managed as a golf course
green, with a 3/32-inch mowing height and with applications of insecticides and
fungicides as needed. Each cultivar is replicated four times.
Penncross ranked first in the trials, as it has the past several years (Table
9), with Emerald ranking second and Penneagle third.
Penneagle dropped in
ranking relative to Penncross in a comparison of 1985 and 1986 data.
It is
uncertain whether this is the result of a deterioration of the Penneagle area
with time, or due to unusually wet conditions in 1986.
Kingstown ranked fourth, but this is due to the fact that much of the Kingstown
velvet bentgrass died and surrounding bentgrasses began to take over the plots.
Prominent and Seaside have survived the past six seasons, both performing
poorly.
In 1985, the quality of bentgrass increased with each increment of applied
nitrogen.
In 1986, this improvement in quality with N level was not observed
(Table 10). Both Penncross and Penneagle had numerically lower ratings at the
higher rates although these differences were not statistically significant.

26

Table 9.

The 1986 q u a l i t y ratings3 for six bentgrass cultivars with
averaged over four replications and three fertility levels.

data

Cultivar

May

June

July

Aug

Sept

Oct

Mean

1.

Penncross

6.7

6.5

7.3

6.1

6.8

6.6

6.7

2.

Emerald

5.6

6.5

6.7

6.3

5.7

6.2

6.2

3*

Penneagle

5.6

6.7

6.5

5.0

6.1

5.3

5.9

4.

Kingstown

5.7

5.9

5.6

6.1

4.8

5.6

5.6

5.

Prominent

4.8

5.3

4.9

6.1

5.5

5.8

5.4

6.

Seaside

4.3

4.8

5.4

6.0

5.1

5.6

5.2

LSD

0.8

1.0

1.0

1.6

1.0

0.8

0.5

3

0.05

Quality based on a scale of 9 to
quality, and 1 = poorest quality.

Table 10. The effects
cultivars.

of

fertility

1; 9 = best quality,

6 = acceptable

level on the quality

of six bentgrass

Cultivar

0.5

lb N/growing season
0.8

1.2

1.

Emerald

6.0

6.0

6.3

2.

Kingstown

5.5

5.7

5.7

3.

penncross

6.9

6.5

6.6

4.

Penneagle

6.2

5.9

5.5

5.

Prominent

5.1

5.8

5.4

6.

Seaside

5.0

5.0

5.5

LSD 0.05 for comparison of fertility levels within cultivar = 1.0.

27

Nitrogen x Potassium Study
K. L, Diesburg and N* E. Christians

This study was initiated to observe the effects of nitrogen (N) and potassium
(K) on turf quality and vegetative growth of Kentucky bluegrass and to evaluate
the interactions between these two nutrients.
The area was seeded with 'Baron' Kentucky^ bluegrass in September 1979. At the
time of establishment, 1 lb P^O^/IOOO ft (triple super phosphate) and 0.5 lb
N/1000 ft
(ammonium nitrate) were applied.
The area is maintained in lawn
condition including 2-inch mowing height, pre- and postemergent weed control,
and irrigation as needed. No insecticides or fungicides have been applied.
The study is arranged in a complete factorial with four levels of N and K each
at 0, 2, 3, and 4 lb/1000 ft /yr. A randomized complete block design is used
with 16 treatments and three replications. Urea is the N source and KC1 is the
source of K. Treatments are split over April, May, late August, and September.
Monthly ratings of turf quality are presented in table 11. Benefit from K was
not as great as from comparable amounts of N.
The beneficial effect from
increasing N application levels was highly significant throughout the season.
Increases occurred between the 0- and 2-lb treatments and the 2- and 3-lb
treatments but not between the 3- and 4-lb treatments.
Higher levels of
applied K, especially between the 2- and 3-lb treatments, caused better turf
quality from June through September.
There was a significant interaction between N and K treatments this year for
the first time since they were begun in 1980. The need for a proper balance of
N and K can be seen in table 11.
Turf quality was actually decreased with
increments of applied K at 4 lb N/1000 ft .
Optimum stimulation of turf
quality from increments of applied K occurred at 0 lb N/1000 ft . Likewise,
optimum improvement of turf quality from increments of applied N occurred at 0and 2-lb K/1000 ft . Turf quality was not affected by increasing the N rate
from 3- to 4- lb/1000 ft at 3- or 4-lb K/1000 ft .

28

Table 11. Turf quality of Kentucky bluegrass in response to N and K treatments.

lb/1000 ft^/year
N
K

_____________________ Ratings3
Apr
Jul
May
Jun
Aug

Sept

Oct

Mean

4
4
4
4

4
3
2
0

5.0
4.7
5.3
6.3

7.0
6.7
7.0
7.3

8.3
7.0
8.0
8.7

8.3
7.7
8.3
9.0

8.3
9.0
8.7
9.0

8.7
8.0
8.3
8.7

6.7
8.0
7.0
7.7

7.5
7.3
7.6
8.1

3
3
3
3

4
3
2
0

5.0
5.7
4.0
5.3

6.0
6.0
6.3
5.7

7.7
8.0
7.7
7.7

8.0
8.0
7.7
7.7

8.7
9.0
8.7
9.0

8.0
7.7
7.7
7.7

9.0
8.7
8.0
7.7

7.5
7.6
7.0
7.2

2
2
2
2

4
3
2
0

4.3
4.7
5.0
4.3

4.7
5.0
5.3
4.7

6.7
7.0
7.3
7.0

7.0
7.7
7.3
6.7

5.7
7.0
6.7
6.0

5.3
6.3
6.3
4.7

8.3
8.0
7.7
8.3

6.0
6.5
6.5
6.0

0
0
0
0

4
3
2
0

4.0
4.7
3.7
3.3

4.0
4.7
3.3
3.3

6.3
4.0
3.0
3.0

6.0
5.7
3.7
4.0

5.3
4.7
3.0
3.0

5.3
5.7
3.3
3.7

5.3
5.3
5.0
5.3

5.2
5.0
3.6
3.7

Experiment Mean

4.7

5.4

6.7

7.0

7.0

6.6

7.3

6.4

LSD

0.8

0.9

0.6

0.7

0.7

0.6

0.6

0.5

0.05

Quality based on a scale of 9 to 1; 9 = best quality
quality, 1 = poorerst quality.

29

, 6 = acceptable

Evaluation of Different Granular Nitrogen
Sources for Fertilization of Kentucky Bluegrass Turf
M. L. Agnew, N. E. Christians, and R. W. Moore

In this study, seven granular nitrogen (N) sources are being evaluated for
maintenance fertilization. The turf, Glade Kentucky bluegrass, was established
in September 1984, and maintained at a cutting height of 2 inches. A randomiz­
ed complete block design with three replications is being used. Plot size is 3
1/2 feet by 7 feet.
2
The treatments include six slow-release N sources applied at 4 lb N/1000 ft /yr
split into two equaj. applications. In addition, one urea treatment was applied
at 4 lb N/1000 ft /yr split into four equal applications.
Treatments were
begun in the spring of 1985.
The dates of fertilizer applications are May 1
and August 15.
The additional urea treatments were applied on June 1 and
September 15. Data taken during the summer of 1986 are listed in table 12.
Urea, Sulfur Coated Urea (SCU)/Anderson, SCU/Lesco, and Plastic Coated Urea
(PCU) treated plots consistently displayed the best visual quality.
The urea
treated plots greened-up earlier, while the PCU treated plots retained a
greener color during the summer months.
In addition, both urea and PCU
retained excellent color through October. Once applied, both SCU treated plots
had very good quality.
An examination of clipping yields demonstrated that
urea, both SCU treatments, methylene urea, and PCU all stimulated more above
ground growth than IBDU and UF.
Treatments will be reapplied and further data will be collected in 1987.

Table 12. Effects
yield.

Nitrogen
Source

of granular

sources

of N on visual

quality

and

clipping

9/12

10/20

Mean

Clipping
Yields
5/30 9/12

3/24

4/19

Visual Quality
5/30 6/25 7/25 8/26

7.0
4.0

8.5
6.2

7.4
6.2

8.0
7.0

7.0
7.2

8.3
6.0

7.0
5.7

9.0
7.0

7.8
6.2

57.9
42.2

74.7
54.6

Urea
IBDU
SCU/
Anderson
SCU/Lesco
Methylene
urea/OMS
UF/Bluechip
PCU/Estech

5.5
4.0

7.1
7.1

7.8
7.9

8.0
7.7

7.8
7.8

9.0
9.0

8.0
7.7

7.7
7.7

7.6
7.4

59.5
60.3

70.8
80.0

4.0
4.0
6.0

6.9
6.1
8.0

6.8
5.5
6.8

7.0
6.5
8.3

7.0
7.3
8.8

8.3
7.3
8.0

7.7
6.0
7.7

7.0
6.7
9.0

6.8
6.2
7.8

57.2
38.2
50.4

77.6
64.0
72.8

LSD

0.5

0.3

0.6

0.2

0.5

0.6

0.8

1.0

0.3

6.9

12.8

0.05

30

Summer Slow-Release Nitrogen Sources Comparison Study
M. L. Agnew, N. E. Christians, R. W. Moore

The purpose of this study was to compare eight slow-release N sources for the
summer application of nitrogen. The turf is Glade Kentucky bluegrass which was
established in September 1984. Treatments were initiated in the spring of 1985
and will continue for several years.
Individual treatment cells measured 5
feet by 5 feet and were randomized in a complete block design with three repli­
cations.
The turf was mowed at 2 inches and water was applied to prevent
drought stress.
Treatments include eight slow-release N sources applied at 2 lb N/1000
ft /season split into two equal applications on May 20 and August 10.
Each
treatment received 2 lb N/1000 ft /season of urea (46-0-0) split into two equal
applications on April 10 and September 20.
One additional treatment, which
included combinations of Powder Blue and urea, was added for comparison (Table
13). Treatment four was Slo-release in 1985 and replaced by N-Sure in 1986.
Visual quality data was collected monthly except for September 1986 (Table 14).
The April data is reflective of the materials applied the previous year. IBDU
and SCU/CIL treatments provided the highest quality. The May data is reflect­
ive of the April urea treatment while the June treatment is reflective of the
May slow release nitrogen sources.
One exception is the N-Sure treatment.
This treatment was not applied until June 6, thus the other N sources had two
weeks to release nitrogen before N-Sure was applied.
The July treatment
demonstrated that SCU/TVA and SCU/CIL released nitrogen at greater rates
during the warm month of July, whereas SCU/TVA, SCU/CIL and Fluf exhibited
greater quality in August.
The final application of urea evened out the
quality of each treatment by October.
Overall, the SCU/CIL and SCU/TVA
treatments exhibited better turfgrass quality.
Clippings were collected from each plot in May and September (Table 14). There
were no differences between any treatments.
Further data will be collected in
1987 and 1988.

31

Table 13.
Treatment
Number

List of treatments.
lbs N per
1000 ft

Date of N
Application

N
Carrier

1

April 10
May 20
August 10
September 20

1
1
1
1

Urea
Powder Blue
Powder Blue
Urea

2

April 10
May 20
August 10
September 20

1
1
1
1

Urea
FLUF
FLUF
Urea

3

April 10
May 20
August 10
September 20

1
1
1
1

Urea
Formolene
Formolene
Urea

4

April 10
May 20
August 10
September 20

1
1
1
1

Urea
N-Sure
N-Sure
Urea

5

April 10
May 20
August 10
September 20

1
1
1
1

Urea
IBDU
IBDU
Urea

6

April 10
May 20
August 10
September 20

1
1
1
1

Urea
SCU - TVA
SCU - TVA
Urea

7

April 10
May 20
August 10
September 20

1
1
1
1

Urea
SCU - CIL
SCU - CIL
Urea

8

April 10
May 20
August 10
September 20

1
1
1
1

Urea
Azolone
Azolone
Urea

9

April 10
May 20
August 10
September 20

1/4 - 3/4
1/2 - 1/2
1/2
3/4 - 3/4

Powder
Powder
Powder
Powder

32

Blue/Urea
Blue/Urea
Blue
Blue/Urea

Table 14.

Comparison of slow-release nitrogen sources in summer fertilization.

Slow Release
Nitrogen
Source

Clipping Yield3
Sept
May

April

Visual Quality*3
Aug
June
July
May

Oct

Powder Blue
Fluf
Formolene
N-Sure
IBDU
SCU/TVA
SCU/CIL
Azolone
Powder Blue/
Urea

47
46
41
48
47
45
40
46
43

57
63
57
61
60
63
61
61
58

7.3
8.5
6.8
7.8
8.0
7.3
8.0
7.0
7.3

7.7
7.7
8.0
7.0
7.3
7.3
7.8
7.0
6.0

6.8
7.2
7.5
6.2
6.8
8.2
8.5
7.0
7.5

7.0
7.0
7.0
7.0
7.0
7.7
7.7
7.0
7.0

7.3
8.7
8.3
8.3
7.0
9.0
8.7
7.7
7.0

8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0

LSD 0.05

NS

NS

0.7

0.8

0.5

0.5

0.9

NS

2
Clippings collected in September are in grams per 1.63 m .
Quality based on a scale of 9 to 1; 9 = best visual quality, 1 = poorest
visual quality.

33

Evaluation of Liquid Fertilizer Programs
on Three Kentucky Bluegrass Cultivars
R. W. Moore, M. L. Agnew,-and N. E. Christians

This study compares 12 liquid fertilizer programs using four nitrogen sources
on three Kentucky bluegrass cultivars.
The treatments were started in the
spring of 1985 and will continue for several years.
The turf is maintained at
a cutting height of 2 inches and all clippings are removed.
The four fertilizers include Urea, Powder Blue, Fluf, and Formolene. They were
applied using different application schedules ^nd three different application
rates.
Each schedule received 4 lb N/1000 ft /growing season.
The balanced
program received 1 lb N/1000 ft in each of the months of April, May, August,
and September.
The heavy spring program received 1/2 lb N in April, 1 1/2 lb
in May, and 1 lb N each in August and September.
The late fall program
required 1/2 lb N in April, 3/^ lb in May, 3/^ lb in August, 1 lb in September,
and 1 lb in November.
The three cultivars of Kentucky bluegrass are Majestic (high-maintenance
grass), Vantage (medium-maintenance grass), and Park (low-maintenance grass).
Each cultivar was replicated three times, and each of the 12 fertilizer
programs were randomized within each cultivar.
The data taken in 1986 include visual quality, clipping weight, carbohydrate
reserves, and root density.
Thatch development will also be measured as the
study progresses.
The field was seeded in the fall of 19811 and sustained substantial winter
damage.
Therefore, the turfgrasses were not ready for ratings until late
summer and early fall.
In addition, early snows in 1985 prevented ratings in
November.
In comparison of the cultivars (Table 15), the visual quality ratings were
generally equal for Majestic, Vantage, and Park.
However, Majestic produced
only half as much clipping weight as Vantage or Park.
This difference is not
surprising since Majestic is a prostrate-growing cultivar.
In comparison of programs (Table 16), the late fall program had the best visual
quality rating in the spring as did the heavy May program through the summer.
The balanced, heavy May and late fall programs responded similarly in the
fall.
Clipping yields did not seem to be influenced by the programs but by
other variables, such as materials and cultivars.
The individual fertilizer ratings demonstrated urea to green up earlier than
Powder Blue, Formolene, or Fluf.
Powder Blue, Formolene, and Fluf did,
however, persist longer during the summer.
Urea had the best overall visual
quality rating followed by Formolene, Fluf, and Powder Blue (Table 17).
Clipping yield data demonstrated urea to have the highest overall rating
followed by Powder Blue, Formolene, and Fluf, respectively. The visual quality

34

data suggest that the slow release nitrogen of the longer chain methylene ureas
becomes more available during the summer.
In reviewing monthly interactions among the variables of cultivars, programs,
and materials, the following conclusions were reached.
In April, before the
first application, the late fall program with urea demonstrated the best
overall visual quality followed by Powder Blue, Formolene, and Fluf (Table 18).
Cultivars and programs in April suggest that there were no significant differ­
ences in cultivars but that the overall visual quality rating was the best for
the late fall program followed by the heavy spring and balanced programs,
respectively (Table 19).
In May, interactions between cultivars and materials suggest that Majestic and
Vantage retained their visual quality as Park's ratings decreased.
Urea still
maintained its visual quality advantage followed closely by Powder Blue, Formo­
lene, and Fluf (Table 20).
Interaction of programs and materials in May
demonstrated that the balanced and late fall programs had the best visual
quality, and urea continued to maintain a high quality rating.
Powder Blue,
Formolene, and Fluf also retained good visual quality, although ratings were
lower than the April rating.
The retention of good visual quality stems from
the 1 lb N received in April on the balanced program and the carryover from the
late fall application (Table 21).
Cultivar and material interactions in June demonstrated that Majestic had the
best overall visual quality.
Urea had a slightly better visual quality rating
than Formolene, Fluf, and Powder Blue. This suggests that after the May appli­
cation was applied, response from materials was relatively equal.
Majestic
responded more favorably than Vantage or Park to the four fertilizer materials
(Table 22).
September interactions between materials and programs demonstrated heavy spring
and balanced programs have better visual quality than the late fall. However,
the late fall program received less nitrogen to date than the other two
programs.
Urea continued to have a good visual quality rating. Formolene and
Fluf also maintained good visual quality ratings, while Powder Blue continued
to show a lower rating due to its slower release characteristics (Table 23).
October comparisons of cultivars and materials demonstrated Majestic to have
the best visual quality rating among the cultivars, whereas urea had the
best quality rating of the fertilizer source (Table 21)).
The comparison of clipping yield data using interactions of cultivars, pro­
grams, and materials demonstrated Majestic to have the least amount of clip­
pings for most of the season (Table 25).
Vantage and Park had comparable
amounts throughout the season.
Urea produced the most clipping yield during
much of the season; however, Powder Blue produced the most clippings during
July.
This may be due to the fact that nitrogen from Powder Blue is released
by microbial action which would be at a peak in July.
In comparison of programs and materials for the season, the balanced and heavy
May programs demonstrated the best visual quality overall. The late fall appli­
cation did result in good spring response, especially from urea and Powder
Blue.

35

The rooting data collected in July of 1986 suggests no significant difference
among cultivars or fertilizer materials.
However, the late fall program
produced significantly more roots in the 0-5 cm and 5-10 cm depth at the July
1986 testing date (Table 26).
These data show the advantage of late fall
fertilization in establishment of a greater amount of rooting in the following
season.
The objective of this study is to observe the long-term effects of these ferti­
lizer materials and programs on the response of the three cultivars. In future
years, such variables as thatch development and carbohydrate status will be
measured.

36

Table 15.

1986 visual quality and clipping yield for 3 Kentucky bluegrass cultivars.

Cultivar

April

May

Vantage
Park
Majestic

6.7
6.6
6.7

6.8
6.U
6.7

7.2
7.1
7.7

6.3
6.1»
6.6

LSD

NS

NS

NS

NS

a
k

0.05

Visual Quality3
June July Sept

Oct

Mean

May

6.5
6.1»
7.5

7.5
7.2
8.3

6.8
6.7
7.3

153
123
70

0.30

0.23

0.13

Clipping Yield13
June July Sept
36
34
30
3.2

11.5

98
76
32
7.5

75
51»
31
4.3

Oct
88
78
47
4.8

Quality based on a scale of 9 to 1; 9 = best quality, 6 = acceptable quality, and
no live grass.
2
Clipping weights are in grams/1.63 in .

Table 16.

1986 visual quality and clipping yields in 3 liquid fertilizer programs.

Program

April

May

Visual Quality3
June July Sept

Balanced
Heavy
spring
Late fall

6.3

6.8

7.3

6.7

6.5
7.1

6.4
6.7

7.9
6.8

LSD

0.20

0.18 0.16

.

0.05

Clipping Yield13
June July Sept

Oct

Mean

May

7.0

7.6

7.0

117

31

66

55

73

6.9
5.8

7.2
6.3

7.8
7.5

7.1
6.7

110
118

38
30

73
67

57
48

74
65

0.29

0.30

0.23

0.13

11. 5

3.3

7.6

4.3

Oct

4.8

Quality based on a scale of 9 to 1 ; 9 = best quality, 6 = acceptable quality, and
no live grass.
0
Clipping weights are in grams/1 .63 in •

Table 17.

1986 visual quality and clipping yields for 4 liquid fertilizers.

Material

April

May

Visual Quality3
June July Sept

Oct

Mean

May

Urea
Powder
Blue
Fluf
Formolene

7.8

7.1

7.5

6.2

7.7

8.3

7.4

149

42

65

62

86

6.5
6.0
6.3

6.8
6.2
6.4

7.0
7.4
7.4

6.9
6.6
6.0

5.5
7.0
7.1

6.1
8.0
8.2

6.5
6.8
6.9

114
91
107

32
30
29

85
67
57

46
51
54

52
71
75

LSD

0.27

0.20 0.19

0.34

0.34

0.26

0.16

0.05

13 .3

Clipping Yield13
June July Sept

3. 8

8.7

5.0

Oct

5.5

Quality based on a scale of 9 to 1; 9 = best quality, 6 = acceptable quality, and 1
no live grass.
Clipping weights are in grams/1.63 m .

37

Table 18. Interaction of program and material on visual quality during April.

Balanced

Heavy Spring

Late Fall

Mean

Urea
Powder Blue
Fluf
Formolene

7.5
6.3
5.7
5.9

7.4
6.4
6.0
6.1

8.5
6.8
6.2
7.0

7.8
6.6
6.0
6.3

Mean

6.4

6.5

7.1

Material

Table 19.

Interaction of cultivar and program on visual quality in April.
Vantage

Park

Majestic

Mean

Balanced
Heavy spring
Late fall

6.2
6.7
7.2

6.3
6.6
6.9

6.5
6.3
7.2

6.0
6.5
7.1

Mean

6.7

6.6

6.7

Program

Table 20.

Interaction of cultivar and material on visual quality during May.
Vantage

Park

Majestic

Mean

Urea
Powder Blue
Fluf
Formolene

7.0
6.9
6.4
6.8

6.8
6.8
6.1
5.9

7.5
6.7
6.1
6.6

7.1
6.8
6.2
6.4

Mean

6.8

6.4

6.7

Material

Table 21.

Interaction of program and material on visual quality during May.
Balanced

Heavy May

Late Fall

Mean

Urea
Powder Blue
Fluf
Formolene

7.5
6.6
6.2
6.7

6.5
6.7
6.1
6.3

7.2
7.2
6.2
6.3

7.1
6.8
6.2
6.4

Mean

6.8

6.4

6.7

Material

38

Table 22.

Material

Interaction of cultivar and material on visual quality during June.

Park

Vantage

Majestic

Urea
Powder Blue
Fluf
Formolene

7.3
7.1
7.2
7.3

7.1
6.9
7.3
6.9

8.1
7.2
7.6
7.9

Mean

7.2

7.1

7.7

Table 23.

Heavy Spring

Late Fall

Urea
Powder Blue
Fluf
Formolene

8.2
5.3
7.0
7.4

7.9
5.6
7.6
7.6

7.0
5.4
6.4
6.3

Mean

7.0

7.2

6.3

Table 24.

Material

7.5
7.1
7.4
7.4

Interaction of program and material on visual quality during
September.
Balanced

Material

Mean

Mean
7.7
5.4
7.0
7.1

Interaction of cultivar and material on visual quality during
October.
Park

Vantage

Majestic

Urea
Powder Blue
Fluf
Formolene

8.0
6.3
7.7
7.9

8.0
5.3
7.7
7.8

8.8
6.7
8.7
8.9

Mean

7.5

7.2

8.3

39

Mean
8.3
6.1
8.0
8.2

Table 25.

The effects of cultivar,
quality and yield.

Data Collected
Visual Quality3
April
May
June
July
September
October

fertilizer program, and fertilizer material on

Cultivar
Vantage
Programs
Heavy Spring

Balanced

Late Fall

PB

FL

FO

U

PB

FL

FO

U

PB

FL

FO

7.7
7.7
7.0
6.7
8.0
8.0

6.2
6.7
7.2
7.0
5.0
6.3

5.2
6.2
7.2
6.3
6.0
7.7

5.8
7.0
7.3
6.0
7.3
7.7

7.2
6.2
8.0
6.0
7.7
8.0

6.7
6.8
7.2
7.3
5.7
6.3

6.4
6.7
7.7
6.7
7.0
7.7

6.4
7.2
8.0
6.7
7.3
8.0

8.4
7.2
6.8
6.0
6.7
8.0

7.0
7.3
6.8
6.3
5.3
6.3

6.3
6.3
6.7
5.7
6.3
7.7

7.2
6.5
6.7
5.3
5.7
8.0

197
39
100
94
108

140
32
108
64
65

130
28
72
63
83

151
30
82
80
95

150
48
79
73
95

171
42
133
70
72

145
44
100
86
99

163
39
116
86
105

165
35
100
84
101

168
38
134
73
68

124
30
91
61
79

130
32
66
65
86

Uc

Clipping Yieldb
May
June
July
September
October
£

k
C

Quality based on a scale of 9 to 1 ; 9 = best quality
and 1 = dead grass.
2
Clippings collected are in grams per 1.63 m .
U = urea, PB = Powder Blue, FL = Fluf, and FO = Formolene.

Table 25.

6 = acceptable quality,

(continued).

Data Collected

Cultivar
Park
Programs
Heavy Spring

Balanced

Late Fall

PB

FL

F0

__U

PB

FL

F0

__U

PB

FL

~ F0

7.1
7.3
6.8
6.3
7.7
8.0

6.3
6.5
6.7
6.7
5.0
5.0

6.0
6.3
7.3
7.0
7.0
7.7

5.8
6.3
7.0
6.3
6.7
8.0

7.6
6.3
8.0
6.7
7.7
8.0

6.4
6.8
7.2
7.0
5.3
6.0

6.0
5.8
8.0
7.3
7.0
7.7

6.2
5.5
7.7
6.7
7.0
8.0

8.4
6.7
6.3
5.3
6.7
8.0

6.2
7.0
6.8
6.3
5.0
5.0

6.2
6.0
6.7
5.7
6.3
7.7

6.8
6.0
6.2
5.3
6.0
7.3

160
35
65
65
103

117
25
86
41
50

109
33
85
57
85

127
32
60
58
85

129
47
75
68
100

123
38
99
50
61

108
38
91
55
83

98
36
60
64
86

158
33
62
54
86

120
33
90
39
46

112
32
80
46
71

111
23
58
45
76

Visual Quality3

__uc

April
May
June
July
September
October
Clipping Yield5
May
June
July
September
October

40

Table 25.

(continued)

Balanced

Data Collected
Visual Quality3
April
May
June
July
September
October

Cultivar
Majestic
Programs
Heavy Spring

Late Fall

PB

FL

FO

__U

PB

FL

FO

__U

PB

FL

F0

7.8
7.6
8.3
7.0
9.0
9.0

6.3
6.7
7.2
7.0
6.0
6.3

5.8
6.2
7.8
7.3
8.0
9.0

6.0
6.7
8.0
6.7
8.3
9.0

7.6
7.0
8.8
6.7
8.3
8.7

6.1
6.3
7.3
7.7
6.3
7.0

5.7
5.8
8.3
7.7
8.7
9.0

5.8
6.5
8.5
6.7
8.3
9.0

8.7
7.8
7.2
5.3
7.7
8.7

7.2
7.2
7.0
7.0
6.0
6.7

6.0
6.2
6.5
5.7
6.7
8.0

6.9
6.5
7.3
5.0
7.3
8.0

131
47
44
41
61

57
27
39
28
40

32
25
33
34
48

53
24
24
31
55

85
48
29
44
61

41
25
35
23
34

28
25
35
30
51

78
24
24
30
46

164
42
37
34
55

85
28
41
24
34

32
16
20
27
37

51
23
26
27
43

Uc

Clipping Yieldb
May
June
July
September
October

Table 26.

1986 Rooting Data (July).

Program

0-5 cm

Balanced
Heavy Spring
Late Fall

168.0a
160.5
182.3

LSD 0.05
£

.0153

Rooting Depth
5-10 cm
10-15 cm
65.5
68.6
76.6
.0072

Rooting weights are in milligrans per 5-cm depth.

41

15-20 cm

43.1
46.0
50.1

32.1
38.1
33.9

NS

NS

Preemergence Crabgrass Control Study— 1986
Z. Reicher, N. E. Christians, and M. L. Agnew

Number one fairway of Homewood Golf Course in east Ames, Iowa, was the site for
the 1986 preemergenee crabgrass control study.
The area was mowed just under
an inch. The soil on the site is a clay loam with a pH of 8.5, a P level of 45
lb/acre, K level of 190 lb/acre, and organic matter content of 10.8 percent.
Treatments included Balan, Bensulide, Dacthal, Team, EL-107, Prodiamine, Prime
+, Pennant, Regalstar, Ronstar 50 WP and 2 G, Pendimethalin, and Cinch.
The
treatments were applied on April 23, 1986.
Immediately after application, the
Ronstar materials on half of each treated plot were watered in with 1/2 inch of
water.
The phytotoxicity ratings were 9 = no damage, 6 = acceptable turf, and 1 = dead
turf.
Only the Pennant and the Ronstar 50 WP showed phytotoxicity at any of
the dates checked (Table 28).
The half plots of the Ronstar 50 WP that were
watered in immediately showed slightly less burn than those that were not, but
still significant burning took place.
Crabgrass counts were made on July 17, 1986. A second count was taken on Sept­
ember 3, 1986, to check the length of control by the herbicides. All the herb­
icides were very effective in controlling the crabgrass at the July 17 count
with the exception of the EL-107 (Table 27). In the September 3 check, none of
the materials differed significantly in control, but Bensulide, Prodiamine,
Prime + (2.4 lb ai/A), Ronstar 50 WP (1.5 and 2.0 lb ai/A), Pendimethalin (3.0
lb ai/A), and Cinch (1.0 lb ai/A) were still over
effective in controlling
the crabgrass.
This was a very wet year in Ames, and germination back into
treated areas was expected.

Table 27.

1986 Preeraergence Annual Weed Control Study.

Rate
lb ai/A

Treatment

1. Control

July 18
Avg. #
%
Crabgrass Control
Plants

September 1
Avg. #
%
Crabgrass Control
Plants

—

63

0

50

0

2. Balan

2.5 G

2

2

97

12

77

3. Bensulide

4

E

7.5

0

100

1

99

4. Dacthal

75

WP

7.5

5

93

15

70

5. Dacthal

75

WP

10.5

0

100

11

79

6. Team

2

G

2

3

96

6

87

7. Team

2

G

3

1

99

5

89

8. Team

28

DF

2

11

82

19

63

9. Team

28

DF

3

4

95

25

50

10. EL-107

75

DF

0.5

20

69

37

26

11. EL-107

75

DF

1.0

12

82

19

62

12. Prodiamine

65

DWG

0.5

2

97

4

92

13. Prime +

1.2 E

1.2

1

99

5

90

14. Prime +

1.2 E

2.4

0

100

1

98

15. Pennant

5

G

2

5

92

7

85

16. Regalstar

1.5 G

2

2

97

5

90

17. Ronstar

50

WP*

1

0

100

7

85

18. Ronstar

50

WP*

1.5

2

98

2

97

19. Ronstar

50

WP*

2.0

0

100

5

91

20. Ronstar

2

G*

3.0

2

98

5

90

21. Pendimethalin

60

WP

1.5

1

99

9

82

22. Pendimethalin

60

WP

3.0

2

97

2

96

23. Cinch

0.5

G

0.75

3

95

10

79

24. Cinch

0.5

G

1.0

1

99

4

92

23

37

NS

NS

LSD

0.05

*
Half of the plot is to be watered in with 1/2 inch water immediately after
application.

Table 28. 1986 Preemergenee Annual Weed Control Study (Phytotoxicity Readings)

Rate
lb ai/A

Treatment
1. Control

4/29

—

Phytotoxicity Readings
5/16
5/7

9

9

9

2. Balan

2.5 G

2

9

9

9

3. Bensulide

4

E

7.5

9

9

9

4. Dacthal

75

WP

7.5

9

9

9

5. Dacthal

75

WP

10.5

9

9

9

6. Team

2

G

2

9

9

9

7. Team

2

G

3

9

9

9

8. Team

28

DF

2

9

9

9

9. Team

28

DF

3

9

9

9

10. EL-107

75

DF

0.5

9

9

9

11. EL-107

75

DF

1.0

9

9

9

12. Prodiamine

65

DWG

0.5

9

9

9

13* Prime +

1.2 E

1.2

9

9

9

14. Prime +

1.2 E

2.4

9

9

9

15. Pennant

5

G

2

9

4.7

2.3

16. Regalstar

1.5 G

2

9

9

9

17. Ronstar

50

WP*

1

4. 7

5.7*

4.7

5.7*

8.7

8.7*

18. Ronstar

50

WP*

1.5

4

5

*

5

5.7*

8

8

19. Ronstar

50

WP*

2.0

3

4

*

4

5

*

4.7

4.7*

20. Ronstar

2

G*

3.0

9

9

*

9

9

*

9

9

21. Pendimethalin

60

WP

1.5

9

9

9

22. Pendimethalin

60

WP

3.0

9

9

9

23* Cinch

0.5

G

0.75

9

9

9

24. Cinch

0.5

G

1.0

9

9

9

LSD

0.05

.25

.71

*

*

.86

*
Half of the plot is to be watered in with 1/2 inch water immediately after
application.

Postem ergence Annual Grass Control Study— 1986
Z. Reicher, N. E. Christians, and M. L. Agnew

The 1986 postemergence annual grass control study was conducted between the
second and seventh fairways of Homewood Golf Course located on the east side of
Ames, Iowa. This area had a fairly thick stand of bluegrass mowed at 3 inches.
The area had never been treated with preemergence herbicides and the crabgrass
population was very high.
The soil on the site is a clay loam with a pH of
8.05, a P level of 2 lb/A, K level of 190 lb/A, and organic matter content of
10.8 percent.
Treatments included American Hoechst's Acclaim in the 0.5 EW and 1 EC formula­
tions at 0.18 and 0.35 lb ai/A and the 1 EC formulation in combinatin with
Bensulide, Dacthal, Pendimethalin, Bromoxynil and 2,4-D, Turflon D, Riverdale's
Triamine, and XRM-4814, an experimental from Dow. Other treatments were Dow's
Tridiphane alone and with Pendimethalin, and Bensulide.
Another Dow experi­
mental, XRM-689, and two PBI Gordon experimentáis, EH-795 and EH-845, were also
included.
The materials were applied at the 3-leaf to 1-tiller stage of the crabgrass
(June 11) and at the 3-leaf to 4-tiller stage (June 24). The herbicides were
applied to a 5 feet by 5 feet plot with a boom sprayer in the equivalent of 120
gal water/A (treatments 14, 15, 16, and 17 were applied in 60 gal water/A).
Overall, the herbicides were very effective in controlling the crabgrass with
100 percent control very common, while less than 80 percent control was rare
(Table 29).
The Acclaim treatments, both alone and in combinations, showed
good control except when mixed with Triamine.
The 0.5 EW formulation of
Acclaim worked equally well as the 1.0 EC formulation. The Tridephane was also
effective alone and in combinations except with the low rate of XRM-4814. The
PBI Gordon experimentáis did not control the crabgrass effectively.
The phytotoxicity was rated as 9 = no damage, 6 = acceptable damage, and 1 =
dead turf (Table 30).
The phytotoxicity ratings were complicated by the
inadvertent application of 3 pts/A of Turflon D over the experiment site on
June 20.
The first phytotoxicity check made before the Turflon D application showed that
only EH-795 and EH-845 reduced turf quality. After the Turflon D application,
the Acclaim treatments showed some burn along with the EH-795 and EH-845, but
recoverd by the final rating date.
The last rating showed the two Acclaim
formulations applied June 24 caused some phytotoxicity.
Again, most of the
phytotoxicity was probably enhanced if not caused by the Turflon D application.
It is interesting to note that weed control was still in the range of 91-100
percent for the Acclaim and Tridiphane treatments made four days after the
Turflon D application.

45

Table

29.

1986 Postemergence Annual Grass Control Study.

Treatment
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.

Control
Acclaim*
Acc + Ben
Acc + Dac
Acc + Pen
Acc
Acc + Ben
Acc + Dac
Acc + Pen
Acc + Brom +
2,4-D
Acc + Turf D
Acc + Tri**
Acc + XRM-4814

14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.

Acc 0.5 EW
Acc 1 EC
Acc 0.5 EW
Acc 1 EC
Acc 0.5 EW
Acc 1 EC
Acc 0.5 EW
Acc 1 EC
Tridiphane
Tridiphane
Tridi + Pen
Tridi + Ben
EF-689
Tridi + XRM-689
Tridi + XRM-689
Tridiphane
Tridiphane
Tridi + Pen
Tridi + Ben
XRM-689
Tridi + XRM-689
Tridi + XRM-689
EH-795
EH-845
LSD

lb ai/A
_
0.18/
0.18/7.5
0.18/7.5
0.18/1.5
0.12
0.12/7.5
0.12/7.5
0.12/1.5
0.18/0.25/
0.25
0.18/0.375
0.18/0.375
0.18/3.0
(Pts/A)
0.18
0.18
0.35
0.35
0.18
0.18
0.35
0.35
1.5
2.0
1.0/2.0
1.0/5.0
0.5
1.0/0.25
1.5/0.5
1.5
2.0
1.0/2.0
1.0/5.0
0.5
1.0/0.25
1.5/0.5
5 oz/1000
5 oz/1000

Date
Applied
6/11 6/24

July 18
Avg. #
%
Crabgrass Control
Plants

September 1
Avg. it
Crabgrass
55
Plants
Control

X
X
X
X
X
X
X
X

57
2
1
0
0
7
0
1
0

0
98
99
100
100
89
100
99
100

56
3
0
0
0
10
0
1
0

0
95
100
100
100
82
100
98
100

X
X
X

1
2
23

99
96
61

3
6
20

95
90
64

9
1
6
3
1
5
1
5
0
1
0
1
0
12
0
0
0
0
10
2
14
11
4
23
35

84
99
89
95
98
91
98
92
100
98
100
98
100
79
100
100
100
100
84
97
77
81
94
60
40

11
4
7
6
5
9
5
5
3
1
1
1
0
13
3
2
4
3
11
4
18
13
4
25
38

80
93
87
90
91
84
91
91
94
98
99
98
100
78
95
96
92
95
80
92
69
77
93
56
31

21

37

21

37

X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X

0.05

*

Plots measure 5 feet by 5 feet . Acclaim treatments 2 - 14 include the 1 EC formula
tion
##
Includes 16.3% 2,4-D; 16.4% 2,4 -DP; 16.255 MCPP.
Acclaim = Acc; Bensulide = Ben; Bromoxynil = Brom; Dacthal = Dac; Pendimethalin = Pen
Triamine = Tri; Tridiphane = Tridi; Turflon = Turf; Starane = Star.

46

Table 30.

1986 Phytotoxicity Annual Grass Control Study.

Treatment

11.
12.
13.

Control
Acclaim**
Acc + Ben
Acc + Dac
Acc + Pen
Acc
Acc + Ben
Acc + Dac
Acc + Pen
Acc + Brom +
2,4-D
Acc + Turf D
Acc + Tri***
Acc + XRM-4814

14.
15.
16.
17.
18.
29.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.

Acc 0.5 EW
Acc 1 EC
Acc 0.5 EW
Acc 1 EC
Acc 0.5 EW
Acc 1 EC
Acc 0.5 EW
Acc 1 EC
Tridiphane
Tridiphane
Tridi + Pen
Tridi + Ben
EF-689
Tridi + XRM-689
Tridi + XRM-689
Tridiphane
Tridiphane
Tridi + Pen
Tridi + Ben
XRM-689
Tridi + XRM-689
Tridi + XRM-689
EH-795
EH-845

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.

LSD
*
**

0.05

lb ai/A
_____
0.18/
0.18/7.5
0.18/7.5
0.18/1.5
0.12
0.12/7.5
0.12/7.5
0.12/1.5
0.18/0.25/
0.25
0.18/0.375
0.18/0.375
0.18/3.0
(Pts/A)
0.18
0.18
0.35
0.35
0.18
0.18
0.35
0.35
1.5
2.0
1.0/2.0
1.0/5.0
0.5
1.0/0.25
1.5/0.5
1.5
2.0
1.0/2.0
1.0/5.0
0.5
1.0/0.25
1.5/0.5
5 oz/1000
5 oz/1000

Date Applied
6/11 6/24

Phytotoxicity Readings
6/18
6/27*
7/8*

X
X
X
X
X
X
X
X

9.0
9.0
9.0
8.0
8.0
9.0
9.0
9.0
9.0

9.0
7.3
7.3
6.3
5.3
9.0
9.0
9.0
8.7

9 .0
8.7
9 .0
8.7
9.0
9 .0
9.0
9 .0
9 .0

X
X
X

9.0
8.0
9.0

7.3
7.3
9.0

9.0
8.7
9 .0

9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
6.3
7.0

9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
9.0
8.0
9.0
9.0
9.0
9.0
9.0
8.7
9.0
9.0
9.0
7.0
8.0

9.0
7.7
7.7
6.3
5.7
7.0
8.3
7.0
5.0
9 .0
9.0
9 .0
9 .0
9 .0
9 .0
9 .0
9 .0
9 .0
9 .0
9.0
9 .0
9.0
9 .0
8.3
9 .0

X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X

1.2

1.4

1.0

Three pts/A Turflan D, applied June 20.
Acclaim treatments 2 - 14 include the 1
Plots measure 5 feet by 5 feet.
EC formulation.
*** Includes 16.355 i?,4 —D ; 16.455 2 ,4-DP; 16.255 MCPP •
Acclaim = Acc; Bensulide = Ben; Bromoxynil = Brom; Dacthal = Dac; Pendimethalin
= Pen; Triamine = Tri; Tridiphane = Tridi; Turflon = Turf; Starane = Star.

Broadleaf Weed Control Study— 1986
Z. Reicher, N. E. Christians, and M. L. Agnew

The 1986 broadleaf control
west of Ames.
The chosen
was heavily infested with
(Plantago major), common
(Trifolium repens).

study took place at the Iowa Arboretum, twenty miles
area was not previously treated with herbicides and
dandelion (Taraxacum officinale), broadleaf plantain
ragweed (Ambrosia artemisfolia), and white clover

Treatments included EH-680, EH-791, EH-737, and Super Trimec from PBI Gordon; a
Ciba Giegy experimental, CGA—52463i Riverdale's Triamine and Triester; and
Dow's Turflon D and XRM—4814.
Treatments were applied on June 18, 1986, a
clear day with no wind.
The temperature was 82°F and relative humidity was
above 60 percent.
There was no precipitation for 24 hours after application.
Herbicide effects were evident by July 1 and final weed counts were taken on
July 16.
All materials were effective in controlling the plantain, dandelion, and white
clover except the CGA-52463.
The ragweed populations were not consistent
enough over the study to get accurate readings.
The experimentáis from PBI Grodon proved to be effective broadleaf control
along with the XRM-4814.
Turflon D, Super Trimec, Triamine, and Triester also
proved to be very effective.

48

Table 31.

1986 Postemergence Broadleaf Weed Control Study.

Material

lb ai/A

Plantain
Mean
%
///plot Cont

Dandelion
Mean
%
///plot Cont

Ragweed
Mean
%
///plot Cont

Clover
Mean
%
///plot Cont

1. Control

—

78

0

14

0

18

0

30

0

2. EH 680

1.69

15

81

2

90

0

100

1

99

3. EH 791

1.45

2

97

0

100

0

100

0

100

4. EH 737

1.69

21

74

0

100

0

100

0

100

5. CGA-52463

0.80

105

0

11

24

12

31

25

15

6. CGA-52463

1.07

116

0

4

71

21

0

17

43

7. CGA-52463

1.78

122

0

13

12

4

80

4

86

8. Triamine

1.50

22

73

0

100

1

98

4

89

9. Triamine

1.96

4

95

2

88

0

100

6

80

10. Triester

2 pt/A

24

70

0

100

9

48

4

89

11. Triester

3 pt/A

7

91

1

95

0

100

1

98

12. XRM-4814

1.24

4

95

1

93

1

94

0

100

13. XRM 4814

1.52

6

91

2

90

0

100

1

98

14. XRM 4814

1.76

3

97

7

52

0

100

4

89

15. TurfIon D

1.12

2

98

9

36

0

100

2

94

16. TurfIon D

1.50

9

86

0

98

0

100

1

98

17. Super Trimec

1.13

11

86

1

97

0

100

0

100

84

NS

8

56

NS

NS

14

46

LSD

0.05

49

Preemergence Herbicide Timing Studies— 1986
M. L. Agnew and N. E. Christians

The purpose of this study was to investigate the effectiveness of five preemer­
gence herbicides when applied on six dates ranging from late fall of 1985 to
late spring of 1986. The herbicides used were Benefin, Bensulide, Bensulide/Devrinol, Dacthal, and Pendimethalin.
The herbicides were applied at rates of
2 lb ai/A (Benefin), 7.5 lb ai/A (Bensulide), 7.5 lb ai/A/1.5 lb ai/A (Bensulide/Devrinol) , 10.5 lb ai/A (Dacthal), and 1.5 lb ai/A (Pendimethalin).
Application dates included November 8, 1985, March 6, March 20, April 4, April
18, and May 6, 1986.
On November 8, an additional treatment of Pendimethalin
at a rate of 3.0 lb ai/A was added.
The area chosen for the study was a nonirrigated Kentucky bluegrass rough at
Homewood Golf Course in Ames, Iowa. Individual plots measured 5 feet by 5 feet
and each was replicated three times. The soil on the site is a clay loam with
a pH of 8.5, P level of 2 lb/acre, K level of 190 lb/acre, and organic matter
content of 10.8 percent.
The environmental conditions in 1986 can be classified as wet, warm, and humid.
Perfect conditions for crabgrass germination were present by May 1, 1986.
On July 16 and September 2, 1986, the number of crabgrass plants per plot were
recorded (Table 32). All treatments significantly reduced the number of crab­
grass plants when compared with the nontreated control.
However, the presence
of 5 or more crabgrass plants per plot is considered unacceptable.
The only
treatments that provided adequate control were: Bensulide/Devrinol on March 20
and April 4; Dacthal on April H, April 18, and May 6; and Pendimethalin on May
6.
None of the materials provided satisfactory control when applied in the
first week of March.
In addition to crabgrass counts on September 2, the number of prostrate spurge
plants were also counted.
The distribution of prostrate spurge throughout the
plots and between replications were inconsistent.
This is exemplified by the
low number of spurge plants in the control and the relatively high number of
spurge plants in other plots. None of the herbicides gave complete control of
spurge although Betasan/Devrinol seems to have some potential.
No spurge
plants were found on plots treated with Dacthal on April it, but they were
present in plots treated on April 18.
The study will be repeated in the fall of 1986 and spring of 1987. The spring
and summer of 1986 were very wet and it is possible that in a drier year,
better control can be obtained with fall and early spring applications.

50

Table 32. Weed control
study.

Herbicide

in the

1986 preemergence annual grass timing control

Rate
Ib ai/acre

Date of
Application

2
2
2
2
2
2
7.5
7.5
7.5
7.5
7.5
7.5
7.5/1.5
7.5/1.5
7.5/1.5
7.5/1.5
7.5/1.5
7.5/1.5
10.5
10.5
10.5
10.5
10.5
10.5
1.5
1.5
1.5
1.5
1.5
1.5
3.0

11- 8-85
3- 6-86
3-20-86
4- 4-86
4-18-86
5- 6-86
11- 8-85
3- 6-86
3-20-86
4- 4-86
4-18-86
5- 6-86
11- 8-85
3- 6-86
3-20-86
4- 4-86
4-18-86
5- 6-86
11- 8-85
3- 6-86
3-20-86
4- 4-86
4-18-86
5- 6-86
11- 8-85
3- 6-86
3-20-86
4- 4-86
4-18-86
5- 6-86
11- 8-85

Crabgrass Count
July 16
Sept 2

Spurge Count
Sept 2

9.3
12.3
20.3
23.7
18.7
24.7
1.7
8.3
1.3
0.3
0.0
0.7
8.0
8.7
1.0
2.0
33.0
9.0
8.0
18.3
11.3
4.0
4.0
3.3
14.0
24.3
18.0
7.0
12.7
4.7
6.0

10.7
13.0
20.3
26.3
18.7
25.7
4.0
11.0
1.3
0.3
0.3
3.0
8.0
8.7
1.0
2.0
33.0
9.0
8.7
18.3
11.7
5.7
4.0
3.7
14.0
24.3
23.7
8.7
14.3
4.7
7.0

1.7
1.7
5.3
3.0
1.7
0.0
4.7
2.3
9.0
3.7
0.3
0.3
2.7
0.0
0.0
0.0
9.0
3.7
1.7
0.7
1.0
0.0
2.0
0.7
1.0
2.3
1.3
0.0
2.3
1.3
1.3

Control

65.3

65.3

2.7

LSD

12.8

12.6

' 5 *3

Balan
Balan
Balan
Balan
Balan
Balan
Bensulide
Bensulide
Bensulide
Bensulide
Bensulide
Bensulide
Ben/Dev*
Ben/Dev
Ben/Dev
Ben/Dev
Ben/Dev
Ben/Dev
Dacthal
Dacthal
Dacthal
Dacthal
Dacthal
Dacthal
Pendimethalin
Pendimethalin
Pendimethalin
Pendimethalin
Pendimethalin
Pendimethalin
Pendimethalin

*

0.05
Ben/Dev = Bensulide/Devrinol.

51

Effects of Preemergence Herbicides on
Rooting of Kentucky Bluegrass— 1986
Z. J. Reicher and N. E. Christians

The objective of this study was to investigate the effects of preemergence
herbicides on rooting of Kentucky bluegrass. The herbicide treatments (express
-ed as lbs a.i.) were Bensulide at 7.5 and 14.0 lb/A, Dacthal at 10.5 and 15.0
lb/A, Balan at 1.6 and 2.4 lb/A, Ronstar at 2.0 and 4.0 lb/A, Pendimethalin at
1.5 and 3.0 lb/A, and Prodiamine at 0.5 and 1.0 lb/A.
An experimental post­
emergence crabgrass control, Acclaim 1EC, was also included at 0.12 lb/A.
The experiment was divided into high-maintenance and low-maintenance regimes.
The high-maintenance study took place on a 3-year-old stand of Midnight
Kentucky bluegrass that received 4 lb N/yr and supplemental irrigation. The
low-maintenance study was located on a 5-year-old Parade Kentucky bluegrass
stand that received only 1 lb N/yr and no irrigation.
Due to the relatively
mild and wet summer, there was little difference between the two regimes. Both
areas were mowed at 2 1/2 inches.
Chemicals were applied on April 25, 1986, and watered in with 2 1/2 inches of
rain that evening.
A core sampler was used to take rooting samples in late
May, late June, and late July. Eight 6-inch deep samples were taken from each
plot and divided into two segments by depth, 1-3 inches and 3-6 inches.
This
was done to check any rooting variability by depth due to the chemicals.
The
samples were washed through a series of screens to remove the sand and soil
particles. Dry weights were taken after the samples were dried at 100°C for 24
hours and weighed. Total organic content of the roots was found by subtracting
the ash weights from the oven dry weights.
The sand and soil particles that
could not be removed by washing were accounted for by measuring the total
organic matter of the roots.
There were no significant reductions in rooting due to the herbicides either by
depth or in total root weight on any of the three sampling dates (Tables 33 and
34).
This could be due to the lack of heat and drought stress on the plants
because of the mild summer.
It has been established that herbicides cause
more damage to the perennial grasses when they are under stress.
This was the second
tion to the field
currently under way
rooting of Kentucky

year of the study that will be repeated in 1987. In addi­
studies, a number of greenhouse and in vitro studies are
to further explore the effect of preemergence herbicides on
bluegrass.

\

52

Table 33.

Average total weight in milligrams of eight root samples/plot in
high-maintenance study.
Rate
lb ai/A

Treatment
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.

Control
Dacthal 75WP
Dacthal 75WP
Ronstar 2G
Ronstar 2G
Bensulide 4E
Bensulide 4E
Balan 2.5G
Balan 2.5G
Pendimethalin 65WP
Pendimethalin 65WP
Prodiamine 65WP
Prodiamine 65WP
Acclaim 1EC
LSD

Table

34.

______
10.5
15.0
2.0
4.0
7.5
14.0
2.0
3.0
1.5
3.0
0.5
1.0
0.12

0.05

Total Root Weight
June 30
July 31

587
621
599
607
597
524
580
608
647
614
634
706
695
593

661
641
719
572
766
530
608
644
574
548
557
655
680
589

554
552
494
512
541
430
524
514
538
536
505
560
647
543

NS

NS

NS

Average total weight in milligrams of eight root samples/plot in
low-maintenance study.

Treatment
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.

May 28

Control
Dacthal 75WP
Dacthal 75WP
Ronstar 2G
Ronstar 2G
Bensulide 4E
Bensulide 4E
Balan 2.5G
Balan 2.5G
Pendimethalin 65WP
Pendimethalin 65WP
Prodiamine 65WP
Prodiamine 65WP
Acclaim 1EC

Rate
lb ai/A

May 28

_____
10.5
15.0
2.0
4.0
7.5
14.0
2.0
3.0
1.5
3.0
0.5
1.0
0.12

LSD 0.05

53

Total Root Weight
June 30
July 31

661
587
647
655
631
598
638
619
627
612
612
617
570
662

792
860
782
825
764
841
929
811
720
759
759
911
818
725

501
518
463
444 *
475
525
447
477
484
423
418
568
503
508

NS

NS

NS

Sod Rooting Study— 1986
Z. J. Reicher and N. E. Christians

For controlling annual grasses in sod re-establishment, there are basically two
alternatives; the first is to use preemergence herbicides immediately after
laying to stop germination and the second is to use the postemergent selective
herbicides to kill the crabgrass after it emerges. One postemergence herbicide
is Acclaim by American Hoescht.
The registration for Acclaim is still pending
with the EPA but it is available under an experimental use permit.
Acclaim
will be labeled for use on grassy weeds such as crabgrass, goosegrass, and
barnyard grass in several established turf species.
The objective of this study was to determine the effects of preemergence herb­
icide applications and timing of Acclaim applications on root growth of freshly
laid sod. There was no crabgrass pressure on this site so weed control was not
observed.
The study took place on an established Kentucky bluegrass sod blend of 25
percent each of the cultivars Adelphi, Glade, Parade, and Rugby.
Herbicides
tested were Acclaim 1 EC at .18 and .36 lb ai/A, Bensulide at 7.5 lb ai/A,
Dacthal at 10.5 lb ai/A, and Pendimethalin at 1.5 lb ai/A.
The Acclaim was
applied at two and four weeks prior to sod cut and two and four weeks after sod
laying. The preemerges were applied over the top of the freshly laid sod. The
sod was cut on July 29 and moved to a prepared sod bed which was rototilled to
a depth of 8 inches and raked level.
The rooting was measured with a technique modified from Beard (Agronomy Journal
61,497-499, 1975).
Sod pieces were transplanted into wooden frames with 18
mesh fiberglass screen bottoms at the time of laying.
The frames were con­
structed of 1 in x 2 in pine boards with inside dimensions of 12 in x 12 in.
At each of the four corners, hook screws were placed for use as the point of
attachment for the hydraulic lift apparatus.
The pump apparatus consisted of a hydraulic jack mounted on a steel plate.
A
bar mounted to a hinge on a pedestal at one side of the plate, attached to the
pump cylinder at the center, and with an eye bolt on the other end being the
attachment point for two woven steel cords. The ends of the cords were attach­
ed to the hook screws on the frames. The eye bolt was centered over the frame
to insure a direct vertical lift.
A gauge measuring hydraulic pressure in
pounds per square inch (PSI) was attached to the pump to facilitate measurement
of force at the point of root breakage from the soil.
After the screens were lifted, a visual measurement of rooting was also taken
on a scale from 9 to 1, with 9 = visible roots through the entire screen, 5 =
roots through 50 percent of the screen area, and 1 = no roots.
Screens were pulled on August 28 and September 26, four and eight weeks after
sod laying, respectively.
Note that the last treatments of Acclaim were not
applied before the first sampling. In the first pulling, there was much
variation among the treatments as seen in table 35, but there were no statis­
tically significant differences in either pump readings or visual ratings. The
54

second sampling revealed that the high rate of Acclaim at both the August 14
and August 29 applications, produced significantly lower rooting according to
the pump readings.
Acclaim at .36 lb ai/A caused some shoot burn on all application dates.
The
phytotoxicity resulting from the July 2 and July 16 applications was probably
enhanced by billbug activity in the plots.
The August 14 and August 29
applications caused significantly more burning than the first two dates.
In summary, Acclaim at .18 lb ai/A compared favorably to the control and to the
preemergence herbicides in root growth and burn potential.
But caution should
be used when applying Acclaim at .36 lb ai/A to freshly laid sod.

Table 35. Results from the 1986 Sod Rooting Study.

lb ai/A

Treatment

Timing

August 29
PSI
Visual

September 26
PSI
Visual

4.4

179

! CO

7/ 2

83

4.7

212

7.3

.36

7/ 2

171

5.3

125

6.3

Acclaim

.18

7/16

146

5.0

210

8.0

5.

Acclaim

.36

7/16

178

4.3

185

7.7

6.

Bensulide

7.5

7/29

150

4.7

130

7.0

7.

Dacthal

10.5

7/29

86

4.7

237

8.7

8.

Pendimethalin

1.5

7/29

107

4.7

187

7.7

9.

Acclaim

.18

8/14

108

4.0

166

8.0

10.

Acclaim

.36

8/14

62

3.0

100

7.0

11.

Acclaim

.18

8/29

—

—

194

7.3

12.

Acclaim

.36

8/29

—

—

92

5.0

NS

NS

67

NS

Control

2.

Acclaim

.18

3.

Acclaim

4.

LSD

—

0.05

55

O

115

1.

Evaluation of Fungicides for Control of
Dollar Spot in Penncross Bentgrass— 1986
M. L. Gleason
Trials were conducted on the Turfgrass Research Plots at the Horticulture
Research Station of Iowa State University near Ames, Iowa.
Fungicides were
applied to Penncross bentgrass maintained at 5/32-inch cutting height ^with a
modified bicycle sprayer at 30 psi and a dilution rate of 5 gal/1000 ft . The
experimental design was a randomized block plan with four replications.
The
plots measured 4 feet by 5 feet.
Fungicides were applied in a 14-, 21-, or
28-day schedule (Table 36). Applications began on June 3 and continued through
September 10.
Plots were evaluated for percent diseased turf on July 24 and
August 29.
Disease ratings for dollar spot were made by counting the number of dollar spot
infection centers per plot. Disease development was very slight throughout the
season, although it gradually increased as the season advanced (Table 36). All
chemically treated plots had significantly less disease than the check, but
none .differed significantly from the others. Most treatments had no disease
throughout the season.
PP523/surfactant at all three rates caused a marked
greening of plots, particularly during late July.
There were no symptoms of
phytotoxicity with other materials.
Table 36. Evaluation
bentgrass.

of fungicides

Treatment

Rate/1000 ft2

for control of dollar
Timing
(Days)

— - Check
SN596 25DF
0.50 oz
SN596 25DF
1.00 oz
H.50 oz
Prochloraz 1»0EC
0.50 oz/1.5 oz
SN596 & Prochloraz
SN596 & Prochloraz
1.00 oz/3.0 oz
1.50 oz
Chipco 26019
2.00 oz
Chipco 26019
U .0
PP523 5
%G/surfactant
g a.i.
6.0
PP523
5%G/surfactant
g a.i.
8.0
PP523
5%G/surfactant
g a.i.
Banner EC
1.00 oz
Bayleton 25 DF
0.25 oz a.i.
0.06 oz a.i.
HWG 1608 25$ WP
HWG 1608 25$ WP
0.12 oz a.i.
HWG 1608 25% WP
0.25 oz a.i.
0.20 oz a.i.
Rubigan AS
2.00 oz
Vorlan
Duosan
3.00 oz
1.00 oz
Fungo

—

21
21
21
21
21
21
21
14
11»
1H
11»
28
21
21
21
21
14
11»
14

spot

in Penncross

Disease Ratings5
July 24
August 29
2.75
0.50
0
0
0.25
0
0.25
0.25
0
0
0
0
0
0.25
0
0
0.75
0
0
0

a
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b

8.50
0.25
1.00
0
0.50
0
0.75
0.25
0
0
0
0
0
0.75
0
0
0
0
0
0

a
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b
b

Average of ratings from four replicated plots.
Based on number of dollar
spot infection centers per plot.
Means in a column followed by the same letter do not differ significantly
(DMRT, P = 0.05).
56

Evaluation of Fungicides for Control of
Leaf Spot on Park Bluegrass— 1986
M. L. Gleason
Trials were conducted on the Turfgrass Reasearch Plots at the Horticulture
Research Station of Iowa State University near Ames, Iowa.
Fungicides were
applied to Park bluegrass maintained at a 1 1/2-inch cutting height
h a
modified bicycle sprayer at 30 psi and a dilution rate of 5 gal/1000 ft . The
experimental design was a randomized block plan with four replications. Plots
measured 4 feet x 5 feet. Fungicides were applied on a 14- or 21-day schedule
(Table 37)Applications began on June 3 and continued through September 10.
Plots were evaluated for percent diseased turf on July 24 and August 29.
Incidence of leaf spot was light until mid-season (July) and decreased in
August.
In the July 24 ratings, Prochloraz EC at a 4.5-oz rate gave the best
control. With one exception, all the other treatments reduced disease severity
significantly in comparison with the check. Disease pressure on August 24 was
so low that differences among ratings on that date are probably meaningless.
No plots showed phytotoxicity symptoms.
Table 37. Evaluation of fungicides for control of Bipolaris leaf spot in Park
bluegrass.
Treatment

Rate/1000 ft2

Check
Prochloraz 40EC
Actidione TGF
Prochloraz & Actidione TGF
Prochloraz & Actidione TGF
Prochloraz & Chlorothalonil
Banner EC
Dyrene 4F
HWG 1608
25% W
P
HWG 1608 25% WP
HWG 1608 25% WP
Vorlan
Duosan
PP523 5% G/surfactant
PP523 5% G/surfactant
PP523
5 % G&
chlorothalonil/surfactant
PP523
5 % G&
chlorothalonil/surfactant
PP523
5%G & Manxate/
surfactant
PP523 5/5 G & Manzate/
surfactant

4.5
0.34
1.5
3.0
6.9
2.0
2.0
0.06
0.12
0.25
2.0
3.0
6.0
8.0
6.0
85.0
6.0
56.6
6.0
95.0
6.0
60.5

a

Timing
(Days)

—

oz

/0.34

oz

oz/0.34 oz
OZ

oz
oz
oz
oz
oz
oz
oz
g
g
g
g
g
g
g
g
g
g

a.i.
a. i.
a.i.
a.i.

a.i.
a.i.
a.i./
a.i.
a.i./
a.i.
a.i./
a.i.
a.i./
a.i.

a
d
cd
cd
cd
cd
cd
cd
be
be
ab
cd
cd
be
be

1.00
0.75
1.00
0.50
1.00
0.25
0.25
0.75
1.00
2.00
1.50
0.75
1.00
1.25
1.00

be
bed
be
cd
be
d
cd
bed
be
a
b
bed
be
b
b

14
14
14
14
14
14
14
21
21
21
14
14
14
14

2.75
0.25
1.00
1.00
1.00
1.00
1.00
1.00
1.50
1.75
2.00
1.00
1.00
1.75
1.50

14

1.25 be

1.00 be

14

1.75 be

1.24 b

14

1.75 be

1.00 be

14

1.00 cd

1.25 b

—

oz
oz

Disease Ratings01
July 24
August 29

Rating represents mean disease severity. 1=trace, 2=light disease symptoms,
3=moderate disease symptoms.
Means in a column adjacent to the same letter do not differ significantly
(DMRT, P = 0.05).

57

Influence of Endophyte Infection of Perennial
Ryegrass on Tolerance to Drought Stress
M. L. Gleason, N. E. Christians, and M. L. Agnew

Several cultivars of perennial ryegrass (Lolium perenne) having a high inci­
dence of infection by a seedborne endophytic fungus (Acremonium loliae) have
recently been released commercially.
A limited amount of evidence suggests
that endophyte-infected perennial ryegrass grows better than endophyte-free
plants under 'stress conditions'.
This possible attribute is mentioned in
advertisements promoting high-endophyte cultivars.
What constitutes 'stress
conditions' is not yet clearly defined. However, some preliminary, unpublished
evidence from Rutgers University suggests that endophyte infection results in
better growth under drought stress.
For this reason, a project was initiated
in 1986 at Iowa State University to assess the role of endophyte infection in
drought stress tolerance.
A grant from the Iowa Turfgrass Institute supported
this research.
In comparing growth of endophyte-infected and endophyte-free plants, it is
important to reduce other sources of variability as much as possible.
A
major source of this extraneous variability is genetic differences among
individual grass plants.
This study compared infected and uninfected plants
derived from the same clones. To obtain endophyte-infected and endophyte-free
plants from the same clone, tillers from the same mother plant were potted
separately.
Half of the tillers were treated for eight weeks with Benomyl
(as a drench) to eliminate the fungus.
This method produced 'same-clonal'
plants with and without endophyte.
Plants originally derived from four mother plants were then potted in sandy
loam soil to which 5 g/1 Osmocote 1ÍJ-1¿1-1IJ had been added. Watering treatments
encompassed a range of water availability to the plants: 0.2 bar (wet), 1 bar
(moist), and 10 bars.
Each pot was watered to saturation when daily weighing
showed that the pot had dried to a weight corresponding to the bar value for
the relevant treatment.
The experimental period was 7 1/2 weeks.
At the end of that time, number of
tillers, dry weight of roots, and dry weight of live and dead blades was
measured for all plants.
The experiment was conducted twice: in fall 1986,
using the cultivar Repelí; and in spring 1987, using the cultivar Manhattan
II. Statistical analysis of data is not yet completed.

58

Sum m er Dormancy Study o f Kentucky Bluegrass Cultivar
M. G. Burt and N. E. Christians
Kentucky bluegrass (Poa pratensis L.) cultivars are known to vary in their
response to environmental conditions and cultural practices. At the Iowa State
University Horticulture Research Station, three trials of the United States
Department of Agriculture (USDA) Kentucky bluegrass cultivar evaluations have
been established.
Each trial consists of 8^ cultivars, with each cultivar
replicated over three 4 feet x 6 feet plots.
The first was established in
September 1980. It is a -Low-maintenance study that receives a September appli­
cation of 1 lb N/1000 ft /yr and is not irrigated. The high-maintenance study
was established in August 1981 and each plot within this trial receives 4 lb
N/1000 ft /yr and supplemental irrigation as needed. The most recent trial was
established in August 1985.
It is a high-fertility, non-irrigated cultivar
trial that receives no supplemental irrigation and 4 lb N/1000 ft /yr.
The
first data will be taken on the high-fertility, non-irrigated study during the
1987 growing season.
Data have been taken on the low- and high-maintenance
trials for the past several growing seasons.
This data is summarized in the
annual Iowa Turfgrass Research Report.
Data from the low-maintenance study were used to develop a summer dormancy
investigation to study the mechanisms of summer-stress survival.
Kentucky
bluegrass cultivars were chosen based on their ratings in the low-maintenance
cultivar trial. The final ranking of each cultivar was considered with special
emphasis on the cultivar's performance during periods of heat and drought
stress.
Five cultivars were picked that consistently have been rated near the
top, or best performing, in the low-maintenance study.
These are K3-162,
Kenblue, Vantage, S. D. Common, and S-21.
Conversely, 5 cultivars were picked
that consistently have been rated near the bottom in the Kentucky bluegrass
low-maintenance trial.
These are Bonnieblue, A-20, Columbia, Lovegreen, and
1-13Seed of these ten cultivars was acquired from the USDA National Turf­
grass Evaluation program.
The 10 cultivars were seeded into separate 12 in x
22 in wooden flats and these are currently being maintained in the Horticulture
Department turfgrass greenhouse.
Grasses develop morphological and physiological adaptations that allow them to
survive periods of summer heat and drought stress.
The literature points to
reasons that may help to explain the Kentucky bluegrass cultivar variability in
the response to, and recovery from these stresses.
Based on the literature,
the following objectives were developed for this research.
Objectives are to
investigate: morphological differences concerning the number of post summerdormancy active lateral buds or reproductive tillers for each cultivar; rooting
depth differences among cultivars; carbohydrate reserve content of the stem
bases and rhizomes of the cultivars; and geographic origin and purpose for the
development and selection of each of the cultivars used in this study.
Information is currently being gathered on the geographic origin and purpose
for the selection and development of each cultivar.
The rooting depth study
will be a greenhouse experiment using a polyethylene tube in PVC pipe. Drought
stressed plants of the 10 cultivars will be harvested during the summer from
the ISU Horticulture Research Station low-maintenance turfgrass plots to be
utilized in the morphological and carbohydrate reserve laboratory analysis.
59

Com parison o f Com paction Alleviation Products— 1986
M. L. Agnew

A study was conducted in 1986 to compare the effectiveness of seven products
and core cultivation, on their ability to alleviate soil compaction and to
study the effects of compaction on plant growth. The study area was a one-year
old stand of Midnight Kentucky bluegrass.
The area was mowed at 2 inches and
irrigated to prevent moisture stress. The area received 4 lb N/1000 ft /yr as
sulfur-coated urea. The list of treatments is given in table 38.
Soil compaction was applied by a smooth power roller that exerted a static
pressure of 2.5 kg cm-2 (35.5 lb in"-).
Compaction was applied twice in 1936,
on May 16 and June 2.
Measurements taken in 1986 included visual quality, shoot density (number of
shoots per 2(1 cm2), verdure (total green shoot dry weight below clipping level
for a 20 cm2 area), bulk density (gm cm-'5), total porosity (percent), and
air-filled porosity (percent).
After much review of the data and statistics, hone of the data taken in 1986
(Table 39) showed any significant difference.
This is both surprising and
difficult to understand.
The only two possible reasons for these results
would be:
(1)

(2)

Undecomposed roots in the samples that were left in the area prior
to establishing the turf. Thé area was once a nursery for ornamental
shrubs.
The thatch layer was measured at 3/4 to 1 1/2 inches thick in places
prior to compaction application.
This could have cushioned the
roller sufficiently to prevent the compaction from occurring.

The results are at best a disappointment for the amount of time and effort that
was exerted on this study.
Careful consideration of extraneous factors, such
as thatch depth, buried debris, and soil texture, should be made before repeat­
ing this study.

60

Table 38. List of treatments
products.
Treatment
Number

Product
Name

for

1986 comparison of compaction alleviation

Rates (per 1000 ft^)

Application
Dates

1
2

Nutra-aide
Nutra-aide

12.8 oz/12.8 oz
12.8 oz/12.8 oz/12.8 oz/12.8 oz

5 '22, 7 '22
5/22, 6/22, 7/22,
8/22

3
1»

Relief
Relief

12.8 oz/12.8 oz
12.8 oz/12.8 oz/12.8 oz/12.8 oz

5/22, 7/22
5/22, 6/22, 7/22,
8/22

5
6

Aqua-gro
Aqua-gro

8.0 oz/8.0 oz
4.0 oz/4.0 oz/4.0 oz/4.0 oz

5/22, 7/22
5/22, 6/22, 7/22,
8/22

7
8

Lesco-wet
Lesco-wet

8.0 oz/8.0 oz
8.0 oz/4.0 oz/4.0 oz/4.0 oz

5/22, 7/22
5/22, 6/22, 7/22,
8/22

9

10

Lesco-wet III
Lesco-wet III

8.0 oz/8.0 oz
8.0 oz/4.0 oz/4.0 oz/4/0 oz

5/22, 7/22
5/22, 6/22, 7/22,
8/22

11
12

Gypsum
Gypsum

50 lbs/50 lbs
25 lbs/25 lbs/25 lbs/25 lbs

5/22, 7/22
5/22, 6/22, 7/22,
8/22

13
14

Core aerator
Core aerator

2 passes/2 passes
1 pass/1 pass/1 pass/1 pass

5/22, 7/22
5/22, 6/22, 7/22,
8/22

15
16

Turftech
Control

.36 OZ/.36 oz

6/22, 8/22

61

Table 39.

Plant and soil responses to chemical and cultivation treatments.

Chemical

Compaction

Shoot
Density

Nutra-aide
(2 apps)

No
Yes

29
28

.35
.40

1.35
1.36

48.1
47.4

17.8
17.0

Nutra-aide
(4 apps)

No
Yes

28
26

.40
.29

1.33
1.36

47.0
46.4

18.0
16.3

Relief
(2 apps)

No
Yes

25
30

.33
.38

1.36
1.38

48.9
46.3

18.5
16.0

Relief
(4 apps)

No
Yes

27
22

.36
.26

1.36
1.45

47.3
47.0

18.7
16.4

Aqua-gro
(2 apps)

No
Yes

23
29

•36
.33

1.39
1.36

46.1
45.8

16.7
16.0

Aqua-gro
(4 apps)

No
Yes

29
30

.32
.33

1.39
1.39

46.3
48.4

15.2
16.7

Lesco-wet
(2 apps)

No
Yes

26
28

.37
.36

1.36
1.38

44.9
46.2

15.0
15.1

Lesco-wet
(^ apps)

No
Yes

32
32

.41
.40

1.35
1.37

48.7
47.1

17.7
15.5

Lesco-wet III
(2 apps)

No
Yes

26
23

.31
.30

1.37
1.37

46.8
47.1

17.1
16.2

Lesco-wet III
(4 apps)

No
Yes

35
24

.44
.28

1.36
1.33

45.2
50.0

15.5
19.0

Gypsum
(2 apps)

No
Yes

37
31

.40
.41

1.36
1.45

46.3
47.7

15.8
16.2

Gypsum
(4 apps)

No
Yes

32
32

.40
.39

1.40
1.38

46.2
46.1

14.9
14.5

Core aeration
(2 passes)

No
Yes

26
24

.31
.31

1.42
1.33

47.3
48.5

15.9
16.4

Core aeration
(4 passes)

No
Yes

25
30

.33
.40

1.33
1.39

47.6
48.1

17.6
16.8

Turftech
(2 apps)

No
Yes

30
21

.43
.29

1.34
1.32

47.4
46.5

17.1
16.9

Control

No
Yes

32
30

.37
.33

1.35
1.38

47.8
46.5

17.8
16.1

NS

NS

NS

NS

NS

LSD 0.05

Verdure

62

Bulk
Density

Total
Porosity

Air-filled
Porosity

Cultivation Equipment Comparison Study
M. L. Agnew, N. E. Christians, and R. W. Moore

In the fall of 1985, a cultivation study was initiated on an area that contain­
ed between 1 and 1 1/2 inches of thatch.
The purpose of this study was to
compare four core aerators and one vertical mower in their capabilities to
remove excessive thatch from a bluegrass stand.
The characteristics of each
machine are listed in table 40. The turf is a Northrup King Premium Sod Blend,
which was established in the fall of 1981.
It is maintained at a cutting
height of 2 inches.
The treatments include five machines and three levels of intensity of applica­
tion.
The three levels of intensity are no passes = OX, 1 pass = 1X , and 2
passes = 2X. When there were no passes made over an area, this is referred to
as a control.
The cultivation was done in September of 1985 and the thatch
depth was measured on September 5, 1986.
The initial thatch depth and the amount of thatch removed after one year is
listed in table 41.
The only treatment not to reduce thatch was the control
for the Ryan Ride-aire.
All other treatments, which include controls for
other machines, decreased thatch.
There were no differences when comparing thatch removal by machine (Table 42).
However, there was a trend that the Ryan Ren-O-Thin and Classen Turf Plugger
demonstrated greater thatch removal.
The Ryan Ren-O-Thin would physically
remove the thatch, whereas the Classen Turf Plugger made 5/8 inch holes that
could potentially help decrease thatch.
When comparing the number of passes made by the total of all machines (Table
43), there was no difference between 1X and 2X. However, the use of cultiva­
tion equipment did decrease the thatch layer over the OX treatment.
This
indicates that 1 or 2 passes with any of the tested machines provided acceler­
ated deterioration of the thatch layer.
This study is being terminated due to difficulties in obtaining all pieces of
equipment.
However, an intensity study was initiated in 1986 to look into the
effect of timing and number of treatments per year of a core aerator and a
verticutter and their ability to decrease thatch.

63

Table 40.

Characteristics of five different pieces of cultivation equipment.

Equipment Name

Equipment Description

Ryan Ryan Ride-aire

Hollow tine, 3 1/2 inches center to center spacing,
1/2 inch tine diameter

Ryan Lawn-aire III

inches
Spoon tine, 3 3 / 4 x 7
spacing, 1/2 inch tine diameter

center

to center

Ryan Lawn-aire IV

inches center
Hollow tine,, 3 3 / 4 x 7
spacing, 1/2 inch tine diameter

to center

Classen Turf Plugger

Hollow tine, 7 x 7 inches center to center spacing,
5/8 inch tine diameter

Ryan Ren-O-Thin

Flail knives,
thickness

Table 41.

1 inch

spacing,

The effect of cultivation equipment
removal on September 5, 1986 •

Equipment
Name

Number of
Passes
Over Area

Initial
Thatch
Depth (cm)a

and

1/8

intensity

OX
1X
2X

2.67
2.67
2.67

-0.17b
0.33
0.67

Ryan Lawn-aire III
Ryan Lawn-aire III
Ryan Lawn-aire III

OX
1X
2X

3.50
3.50
3.50

1.00
1.40
1.50

Ryan Lawn-aire IV
Ryan Lawn-aire IV
Ryan Lawn-aire IV

OX
1X
2X

2.57
2.57
2.57

0.13
0.50
0.70

Classen Turf Plugger
Classen Turf Plugger
Classen Turf Plugger

OX
1X
2X

2.67
2.67
2.67

0.07
0.73
1.00

Ryan Ren-0-Thin
Ryan Ren-0-Thin
Ryan Ren-O-Thin

OX
1X
2X

3.17
3.17
3.17

0.83
1.50
2.00

1 inch = 2.54 cm
A negative number indicates an increase in thatch depth.
64

blade

on thatch

Amount of Thatch
Removed (cm)

Ryan Ride-aire
Ryan Ride-aire
Ryan Ride-aire

a
b

inch

Table 42.

The effect of cultivation on thatch removed on September 5, 1986.

Equipment
Name

Amount of Thatch removed (cm)
without control

Ryan Ride-aire

0.67

Ryan Lawn-aire III

0.45

Ryan Lawn-aire IV

0.47

Classen Turf Plugger

0.81

Ryan Ren-O-Thin

0.92

Table 43.

The effect of cultivation intensity on thatch removal on September
5, 1986.
.Amount of Thatch
Removed (cm)

Number of Passes
over area

OX

0.37

1X

0.89

2X

1.17
0.44

LSD 0.05

65

Comparative Effectiveness of Insecticides
Against Annual White Grubs— 1986
D. L. Lewis and N. E. Christians

Damage to turfgrass by annual white grubs (Cyclocephala spp.) is a common, but
spotty and locally severe problem in Iowa.
Amount of damage varies greatly
from place to place and from year to year, depending on several factors such
as grass variety, cultural maintenance practices, irrigation, and weather.
Root feeding by these masked chafer larvae characteristically causes grass to
wilt, turn tan, and finally die, usually in late August or early September.
Several granular and emulsifiable concentrate insecticide products are regis­
tered for white grub control.
Timing of insecticide application is very
important in achieving effective control of white grubs before damage becomes
severe.
The objective of this study was to evaluate and compare the efficacy of sever­
al registered and experimental insecticides against annual white grubs infest­
ing turfgrass.
The study was conducted on fairway and rough areas of the Hyperion Golf and
Country Club located in Johnston, Iowa (Polk County).
Two separate tests of
the same design were conducted.
In the first test the insecticide treatments
were applied on August 5, 1986, and grub population counts were taken August
20, 1986.
The second test treatments were applied on September 3, 1986, and
the efficacy data collected on September 25. 1986.
The experimental design consisted of 15 treatment plots and one untreated
check plot, randomly assignee^ in each of three replications.
Each plot
consisted of a 5 feet by 5 feet area.
All insecticides were applied at the
rate specified on the manufacturer’s label or product guidelines.
Liquid
insecticides were applied with a compressed gas, back-pack sprayer, connected
to a hand-held, three-nozzle boom.
The boom covered a 5 feet wide area, and
diluted insecticide spray was applied to the test plots with alternating
perpendicular passes over the treatment plot.
The amount of water applied to
each plot was the equivalent of 175 gal/acre.
Granular insecticides were
premeasured into round, cardboard containers and applied uniformly over the
plot by shaking through a perforated lid. In the first study, the insecticides
were watered into the turfgrass immediately after application with approximate­
ly 1/2 inch of irrigation. In the second test, irrigation was not necessary as
application was made late in the day just prior to an evening shower in excess
of one inch.
Annual white grub population counts were made approximately three weeks after
treatment by randomly selecting sample sites within each plot, removing the
sod, and counting all live white grubs found.
The sod was lifted from the cut
area, and the root mass carefully cut apart and examined for living grubs. The
soil beneath the cut sod was scratched loose to a depth of two inches and
similarly examined.
The total number of white grubs found in each sample was
recorded.

66

For the first study, three samples were taken in each plot.
Each sample
consisted of a plug cut with a standard 4-inch diameter golf green cup cutter.
In the second study, four samples were taken in each plot.
The samples were
6-inch squares of turfgrass cut loose with a long, sharp knife.
Population
counts in the samples were converted to number of white grubs per square foot
for analysis and reporting.
The insecticides used in this project, the formulation, rate of application,
and mean number of white grubs per square foot are given in table 44, Signifi­
cant differences among treatments and between treatments and the untreated
check are difficult to determine from these data, especially in the first test.
Conclusions are difficult to draw because of low numbers of white grubs and
large variation in population density among replications and among plots within
replications.
However, nonrestricted least significant difference (LSD) test
values indicate there were significant reductions in white grub numbers in the
treatment plots compared to the check plots.
In the first study, all treatments except the 2 lb rate of CGA-73102 apparently
reduced white grub numbers compared to the control plots.
The fact that
CGA-73102 at the lower rate (1 lb ai/A) did show significant reduction further
indicates that the white grub population was highly variable in the test area.
This experimental product provided control at both the high- and low-rate in
the second study.
The second study was initiated on an area that was heavily infested with white
grubs prior to insecticide application.
We consider the results in this test
to be more reliable.
In the second study, CGA-12223 was the only product to
provide complete white grub control.
Dursban 50W at the .5 lb rate was not
effective in controlling white grubs although the 1 lb rate gave very good
control (91 percent reduction).
Dursban 4E and Dursban ME were effective at
both tested rates.
Mocap provided very good control at the low- and highrate, whereas diazinon 4E yielded inconsistent results.
Turcam 76WP was not
effective in controlling white grubs in this test. This is surprising in light
of other experiences with this product where excellent control has been
achieved.

67

Table 44.

Effects of commercially available and experimental insecticides on
annual white grubs infesting turfgrass, Polk County, Iowa, 1986.

Insecticide /
Formulation
Control
CGA-73102 5G
CGA-73102 5G
CGA-12223 2G
Oftanol 2E
Dursban 50W
Dursban 50W
Dursban 4E
Dursban 4E
Dursban ME
Dursban ME
Mocap 10G
Mocap 10G
Diazinon 4E
Diazinon 4E
Turcam 76WP
LSD**
*

Mean number white grubs
per square f o o t __
Second
First
Study*
Study*

Rate
lb ai/A

12
1
8
0
3
0
4
0
1
0
0
0
0
0
1
3

1.0
2.0
2.0
2.0
0.5
1.0
0.5
1.0
0.5
1.0
5.0
10.0
2.7
5.4
2.1

8.0

0.05

11
2
2
0
3
6
1
2
3
2
2
1
1
3
5
6
7.3

Treatment data/population count date:
First Study - August 5 / August
20. Second Study - September 3 / September 25
nonrestricted LSD; model not significant at the 0.05 level.

68

Iowa State University Personnel
Affiliateci with the
Turfgrass Research Program

1

DR. MICHAEL AGNEW

Assistant Professor, Extension Turfgrass Specialist.
Horticulture Department.

^
^

MR. MICHAEL BURT

Turfgrass Graduate Student and Research Associate.
Horticulture Department M.S. (Christians).

%
4

DR. NICK CHRISTIANS

Associate Professor, Turfgrass Science.
Research and Teaching. Horticulture Department.

§

MR. KEN DIESBURG

Turfgrass Graduate Student and Research Associate.
Horticulture Department Ph.D. (Christians).

|
|

DR. MARK GLEASON

Assistant Professor, Extension Plant Pathologist.
Plant Pathology Department.

t

MR. ROBERT HARTZLER

Extension Weed Associate, Weed Science Department.

DR. CLINTON HODGES

Professor, Turfgrass Science.
Research and Teaching. Horticulture Department.

MR. YOUNG JOO

Turfgrass Graduate Student and Research Associate.
Horticulture Department Ph.D. (Christians).

DR. DONALD LEWIS

Associate Professor, Extension Entomologist.
Entomology Department.

MR. RICHARD MOORE

Turfgrass Graduate Student and Research Associate.
Horticulture Department M.S. (Christians/Agnew).

MR. ZACHARY REICHER

Turfgrass Graduate Student and Research Associate.
Horticulture Department M.S. (Christians).

69

1

Companies and Organizations That Made Donations to the
Iowa State University Turfgrass Research Program
Special thanks is expressed to the Big Bear Turf Equipment Company and Cushman
Turf for providing a Cushman Truckster for use at the research area in 1986, to
Tri-State Turf and Irrigation for providing a Greensmaster III Triplex Greensmower for use on the research green this year, and to the Toro Company and
Tri-State Turf and Irrigation for providing a Toro 8*1 Triplex mower for use in

1986.

American Hoechst Corporation
Agricultural Chemicals Department
Route 1 - Box 7
Brownsdale, Minnesota 55918

Cushman Turf
5232 Cushman
Lincoln, Nebraska

W. A. Cleary Corporation
1049 Somerset Street
Somerset, New Jersey 08873

The Andersons
Post Office Box 119
Maumee, Ohio 1*3537

D & K Turf Products
8121 Parkview Drive
Urbandale, Iowa 50322

Aquatrols Corporation of America
1432 Union Avenue
Pennsauken, New Jersey 08110
Arcadian Corporation
310 Clapp Farms Road
Greensboro, North Carolina

68501

Dow Chemical
10890 Benson - Suite 160
Shawnee Mission, Kansas 66210
27406
Dupont Incorporated
1007 Market Street
Wilmington, Delaware

Big Bear Turf Equipment Company
1840 Fuller Road
West Des Moines, Iowa 50265

19898

Britt Tech Corporation
Post Office Box 216
Britt, Iowa 50423

Elanco Products Company
5600 South 42nd Street
Post Office Box 3008
Omaha, Nebraska 68103

Chesebrough-Pond's, Inc.
Research Laboratories
Trumbull Industrial Park
Trumbull, Connecticut 06611

Fermenta Plant Protection Company
Post Office Box 348
7528 Auburn Road
Painesville, Ohio 44077

CIBA-Geigy Corporation
Agriculture Division
Greensboro, North Carolina

GrassRoots Turf
6143 Southwest 63rd
Des Moines, Iowa 50321

27049

Hawkeye Chemical Company
Post Office Box 899
Clinton, Iowa 52732

Classen Manufacturing
1403 Rouch Street
Norfolk, Nebraska 68701

70

Regal Chemical Company
Post Office Box 900
Alpharetta, Georgia 30201

International Seeds
820 First Street
Post Office Box 168
Halsey, Oregon 97348

Rhone-Poulenc Chemical Company
Black Horse Lane
Post Office Box 125
Monmouth Junction, New Jersey

Iowa Golf Course Superintendents
Association

08852

Iowa Professional Lawn Care
Association

Riverdale Chemical Company
220 East 17th Street
Chicago, Illinois 60411

Iowa Turf Producers and
Contractors

0. M. Scott and Sons
Marysville, Ohio 53040

Iowa Turfgrass Institute
Lebanon Chemical Corporation
Country Club Fertilizer Division
Post Office Box 180
Lebanon, Pennsylvania 17042

Spraying Systems Company
N Avenue at Schmale Road
Wheaton, Illinois 60187

LESCO Incorporated
300 South Abbe Road
Elyria, Ohio 44035

Stauffer Chemical Company
10250 Regency Circle
Omaha, Nebraska 68114

Loft-Kellogg Seed
322 East Florida Street
Post Office Box 684
Milwaukee, Wisconsin 53201

Par Ex
Swift Agricultural Products Corp.
518 Pauline Drive
Buffalo Grove, Illinois 60090

M & A Enterprises
4346 South 90th
Omaha, Nebraska 68127

Terra Chemical Corporation
Box 218
Quimby, Iowa 51049

Monsanto Company
Agricultural Products Division
800 North Lindbergh Boulevard
St. Louis, Missouri 6 3 167

The Toro Company
Irrigation Division
Riverside, California

92500

Tri State Turf & Irrigation Co.
6125 Valley Drive
Bettendorf, Iowa 52722

Nor-Am Chemical Company
3509 Silverside Road
Post Office Box 7495
Wilmington, Delaware 19803

Union Carbide
Agricultural Products
Ambler, Pennsylvania 19002

PBI/Gordon Corporation
1217 West 12th Street
Post Office Box 4090
Kansas City, Missouri 64101-9984
Pickseed West Incorporated
Post Office Box 888
Tangent, Oregon 97389

71

In the rush to prepare this information for the field day report, some
companies may have inadvertently been missed.
If your company has
provided financial or material support for the research program, and is
not mentioned above, please contact me so your company name can be
added in future reports.
Nick E. Christians

72

4i±- and justice for all

The Iowa Cooperative Extension Service’s programs and
policies are consistent with pertinent federal and state laws
and regulations on non-discrimination regarding race, color,
national origin, religion, sex, age, and handicap.

Cooperative Extension Service, Iowa State University of
Science and Technology and the United States Department of
Agriculture cooperating. Robert L. Crom, director, Ames, Iowa.
Distributed in furtherance of the Acts of Congress of May 8
and June 30, 1914.