Record

Volume 34, Number 4 

July/August 1996

The Ups 
and Downs 
of Rolling

A PUBLICATION ON TURFGRASS MANAGEMENT

BY THE UNITED STATES GOLF ASSOCIATION®

1894

JULY/AUGUST1996 
Volume 34, Number 4

Cover Photo: 
Rolling can improve 
green speed and 
smoothness.

USGA® GREEN SECTION “■

Record

The Ups and Downs of Rolling Putting Greens 
A practical guide for developing a rolling program. 
By Chris Hartwiger

Water Quality Monitoring at Queenstown Harbor 
The results of five years of groundwater monitoring on a 
golf course located in an environmentally sensitive area. 
By Frank Wm. “Bill” Shirk

Optimizing the Turfgrass Canopy 
Environment with Fans
Fans can help overcome poor growing environments. 
By Patrick M. O’Brien

13

Physiological Management of Bipolaris sorokiniana 
Leaf Spot Symptom Expression by Kentucky Bluegrass 
A unique approach to disease management that involves 
suppression of visual symptoms. 
By Dr. Clinton E Hodges
17
Hand Watering Greens 
There is a correct way. 
By Pat Gross 

18 
Thirsty Turf
A short course in water conservation.
By Ron Dodson
21
News Notes
24
Sensible Choices
Making better choices of new bentgrass varieties.
By Paul Vermeulen
26
Turf "Busters

Oscillating fans are a popular new tool 
used in golf course maintenance 
programs. See page 9.

Weather stations located on the golf 
course provide valuable information 
that is used in irrigation programs. 
See page 18.

Rolling during golf tournaments is a common practice to maximize green speed and improve putting quality.

The Ups and Downs 
of Rolling Putting Greens

A practical guide for developing a rolling program.

by CHRIS HARTWIGER

HISTORY has an uncanny ability 

to repeat itself. Nowhere is this 
more apparent than in the turf­
grass management practice of rolling 

putting greens. Once an important tool 
in a superintendent’s management pro­
gram in the early 1900s, the practice of 
rolling has endured periods of popu­
larity and disdain. Nevertheless, rolling 
putting greens has received consider­
able attention during the early 1990s, 
and its merits are being debated at 
many golf courses.

The attitudes toward rolling vary 
widely today. Some golf course super-

intendents view rolling as a means of 
improving putting quality, while others 
believe rolling is just another stress 
that makes putting green management 
just that much more difficult. While the 
debate over rolling continues, a large 
portion of the golf course management 
industry is interested in revisiting this 
old maintenance practice and learning 
about its potential for use today.

This article will serve as a guide to 
developing an agronomically appro­
priate greens rolling program through 
careful consideration of several factors. 
To accomplish this, a brief history of 

rolling and the advantages and disad­
vantages associated with greens rolling 
will be reviewed. Next, research results 
on the effects of rolling putting greens 
will be presented in order to under­
stand appropriate frequencies of rolling 
putting greens. Finally, the different 
types of rollers available today will be 
reviewed, and methods to compare 
different rollers will be offered.

Rolling History

Historically, superintendents used 
rolling as a supplement to mowing to 
improve the smoothness of putting 

JULY/AUGUST 1996

1

greens. The mowing equipment, turf­
grass varieties, and cultural practices 
for putting greens during the early 
1900s were much less sophisticated 
than those available today, and the 
practice of rolling provided an imme­
diate improvement in putting con­
ditions. As golf course management 
evolved, the attitudes about rolling 
changed too. New bentgrass varieties 
and improved mowers allowed super­
intendents to make major improve­
ments in putting quality. Also, turfgrass 
scientists discovered the negative 
effects of compaction on turfgrass 
growth and development. Needless to 
say, many rollers were relegated to the 
back comer of the equipment storage 
facility.

Several events have occurred during 
the last 20 to 30 years that have made 
superintendents reconsider the prac­
tice of rolling putting greens. The first 
is the proliferation of high-sand-con- 
tent putting greens, which are less 
susceptible to compaction. Also, many 
equipment manufacturers have 
introduced new lightweight rollers 
designed specifically to provide an 
efficient and reliable means of rolling 
greens. A final consideration is the 
increasing pressure being placed on 
superintendents to provide faster and 
smoother putting surfaces.

Rolling Perceptions

With the renewed interest in roll­
ing, is is important to understand the 
potential advantages and disadvan­
tages associated with an appropriate 
putting green rolling program. Under 
reasonable mowing heights, rolling 
will increase green speed. Accompany­
ing the benefit of green speed is an 
improvement in smoothness and 
uniformity. After rolling, improved 
smoothness is readily apparent, 
especially to golfers. Some superin­
tendents roll greens in conjunction 
with mowing, while others roll as a 
substitute for mowing. This approach 
reduces the stress associated with 
mowing and can smooth spike marks, 
remove dew, and provide an immediate 
improvement in smoothness.

While golf’s Scottish ancestors con­
sidered inconsistent greens a challenge, 
the demands of today’s players dictate 
a consistent surface from the first green 
through the 18th green. Rolling all 18 
greens can improve the uniformity and 
consistency of speed among greens.

Aerification is a practice that’s essen­
tial for high-quality putting greens, but 
unfortunately golfers have a poor

2

USGA GREEN SECTION RECORD

Historically, golf course superintendents used rolling as a mowing supplement in 
turfgrass management programs.

understanding of this practice. Some 
superintendents are using rolling as a 
way to minimize the surface disruption 
caused by aerification and improve 
post-aerification putting quality for 
golfers.

Equipment used to maintain turf­
grass has limitations, and rollers are 
no different. Over the years, several 
areas of concern with rolling have 
arisen. Turf scientists have demon­
strated that compaction hinders turf­
grass growth, and some fear that rolling 
increases compaction. Along with this 
change, some believe that rolling may 
cause a decrease in the infiltration rate 
that could hinder oxygen and water 
availability to the roots. Also, there is a 
concern that rolling may result in wear 
injury or bruising of the turfgrass on 
the putting green.

Until recently, researchers had not 
investigated these concerns, and the re­
sult was a cautious approach to rolling 
by superintendents. For example, some 
use rollers prior to a tournament or 
special event and use it sparingly at 
other times. Two major forces are 
driving this conservative approach. 
The first is a lack of research on the 
effects of rolling. Additionally, superin­
tendents do not want to raise golfers’ 
expectations without knowing more 
about the negative effects of rolling.

The Effects of Rolling

If the practice of rolling is to find its 
place in the future of putting green 
management programs, several impor­
tant issues need to be resolved. First, 

the practice of rolling appears to 
increase green speed, but both the 
immediate effects on green speed and 
the residual effects on green speed are 
not understood completely. Also, turf 
managers are aware of the negative 
effects associated with compaction, 
but no one has determined if the new 
lightweight rollers compact putting 
green soils. Finally, examples of rollers 
injuring turf through abrasion have 
been observed, but little is known 
about what conditions and frequencies 
of rolling can cause this injury.

In 1992,1 identified these questions 
and initiated a research project at 
North Carolina State University under 
the guidance of Drs. Joe DiPaola, 
Charles Peacock, Leon Lucas, and Bill 
Cassel. The goal of this project was to 
evaluate the effects of lightweight roll­
ing on green speed, compaction, and 
turf quality. This experiment was con­
ducted on bentgrass greens constructed 
with a USGA specification rootzone 
and a native soil rootzone. The initial 
study was conducted for 10 weeks in 
the summer of 1993 and was repeated 
in the summer of 1994. Rolling fre­
quencies on the bentgrass test plots 
were either 0,1,4, or 7 times per week.
Outlined below is a brief summary of 

the results of this research.

Green Speed — The experiments 
performed on green speed revealed two 
important points. First, green speed 
measurements taken one to two hours 
after rolling were 10 to 15 percent faster 
than an untreated area. Also, a residual 
effect was observed. Approximately 48 

hours after rolling, the plots receiving 
the rolling treatment had green speeds 
approximately 2 to 4 percent faster 
than untreated plots.

Bulk Density — Bulk density mea­
surements were used to assess the level 
of compaction of both the USGA and 
native soil rootzones. On the USGA 
specification green, no change in com­
paction was detected in either of the 
treatment years for any of the rolling 
frequencies. In essence, rolling as much 
as seven times per week for ten weeks 
did not produce a measurable change 
in bulk density.

On the native soil green, mixed re­
sults were observed. In the 1993 experi­
ment, rolling frequencies of four or 
seven times per week produced an 
increase in bulk density. No change in 
bulk density was noted for the plots 
receiving zero or one rolling treatment 
per week. In the second year, no 
change in bulk density was detected 
regardless of rolling frequency.

Turf Quality — Results of the study 
indicated that, depending on the roll­
ing frequency, turfgrass thinning and 
decreased turf quality can result from 
rolling. At a frequency of rolling one 
time per week, no decrease in turf 
quality was evident when compared 
to an untreated plot. However, rolling 
frequencies of four or seven times per 
week did result in turfgrass thinning 
after approximately three to four weeks

of rolling treatments. When thinning 
did appear, it began in isolated areas 
and increased as treatments continued. 
Rolling four or seven times per week 
did reduce turf quality, but only if 
practiced for several consecutive 
weeks. Therefore, superintendents can 
roll at low frequencies for extended 
periods of time and at high frequencies 
for short durations.

Types of Rollers

There are three primary types of 
rollers available for putting greens. The 
drum roller is the oldest type of roller 
in use today. Drum rollers have been 
used for many years and they vary in 
size, shape, and weight. Typically, these 
units were constructed by a creative 
golf course mechanic. During opera­
tion, drum rollers are pulled behind a 
utility vehicle.

The second type of roller is called a 
triplex attachment. These rollers are 
attachments substituted for the reels on 
a triplex mower. The actual operation 
of these units is virtually identical to 
mowing a green with a triplex mower. 
As a result, little operator training is 
needed for effective use. A difference 
between these units and the other two 
categories is that tires of the triplex, 
and not the rollers themselves, are the 
last part of the unit to impact the turf.

Dedicated lightweight rollers are the 
third category of roller available today. 

Research at North Carolina State University demonstrated that rolling 
once a week did not decrease turf quality. Turf quality declined after rolling 
the turf four or seven times per week after a period of three to five weeks.

Turf Quality: Native Green 1993

Turf Quality, 
1-9(9 = Best) 

These units have been receiving the 
majority of the publicity surrounding 
the renewed interest in rolling. 
Designed only to roll putting greens, 
these models come in a variety of sizes, 
shapes, and weights. The major differ­
ences between various models of dedi­
cated lightweight rollers are the number 
and size of actual rollers on the unit, 
the presence or absence of hydraulics, 
and the weight of the unit. A dedicated 
lightweight roller usually has two or 
three rollers underneath the unit. The 
presence of hydraulics, which is a 
source of concern to superintendents 
who worry about hydraulic leaks, is 
found on some of the models, while 
others have a belt-only drive system 
with no hydraulics.

Comparing Rollers

Choosing the type of roller for your 
golf course is an important decision 
that involves several factors. The cost 
of the roller is a key consideration. 
Typically, drum rollers are least expen­
sive, followed by triplex attachments 
and dedicated lightweight rollers. The 
need for operator training must be 
examined closely. Triplex attachment 
rollers require the least amount of 
operator skill, while dedicated light­
weight rollers are the most difficult to 
operate. The terrain of the greens and 
surrounds can dictate the level of 
operator skill needed. The more un­
dulations or steep slopes present, the 
greater the need for operator skill and 
the capability of a roller to handle these 
conditions.

The amount of force per unit area 
that a roller imparts on the green is 
another important consideration. His­
torically, measures such as pounds per 
square inch (PSI) or pounds per lateral 
inch (PLI) have been used to determine 
the force applied to a green by a piece 
of turf equipment. Unfortunately, both 
PSI and PLI are difficult to apply to 
rollers. PSI and PLI will be reviewed 
to understand their limitations, and a 
formula called the Roll Factor will 
be presented as a means to compare 
the compaction potential of different 
rollers.

In simple terms, PSI can be calcu­
lated by dividing the weight of the roller 
by the area of surface contact. Often, 
the technical specifications for the 
roller will contain the weight, but not 
the areas of surface contact. On a 
concrete floor, the surface area is easy 
to determine. Unfortunately, rollers are 
used on a putting green and not on 
concrete. When a roller is placed on a

JULY/AUGUST 1996

3

other turf equipment used on the golf 
course.

The “Do’s and Don’ts” of Rolling

Now that we have reviewed the 
effects of rolling on the putting surface, 
the types of rollers available, and a 
method to compare rollers, some final 
thoughts on developing a rolling pro­
gram are in order.

Realize that a roller is a tool and not 
a quick fix or a substitute for a good 
agronomic program. As demonstrated 
through research, proper frequencies of 
rolling can improve the smoothness 
and speed of a green. Generally, low 
rates of rolling, such as once or twice 
a week during non-stress periods, can 
be practiced without detriment to the 
turf. Higher rates of rolling can be 
practiced for short durations only. 
When injury occurs, it is gradual and 
does not happen overnight. However, 
high frequencies of rolling, such as 
four or seven times per week for an 
extended period, may result in dimin­
ished turf quality.

Rolling does not always have to be 
used as a means to improve existing 
green speed. During the off-season, 
when clipping production is minimal, 
rolling greens is an excellent means to 
remove dew and provide a putting sur­
face comparable to a freshly mowed 
green. Rolling also can be used after 
aerification as a way to minimize the 
surface disruption associated with this 
practice.

The education of golfers and course 
officials is essential to any rolling pro­
gram. Spoiling golfers with continual 
rolling may help create a standard that 
no one can sustain. It is important to 
make a distinction between the proper 
and improper use of a roller. There are 
times when rolling can be practiced 
and time when rolling is not advised. 
The more these groups understand the 
principles of a proper rolling program, 
the more successful the superintendent 
will be.

It is not known whether the practice 
of rolling will continue to follow a 
roller coaster of popularity. What is 
known is that superintendents now 
have more information about the 
effects of rolling and a wider choice of 
rolling equipment. This information 
can be used to develop an agro- 
nomically appropriate greens rolling 
program that will benefit those who 
enjoy golf.

CHRIS HARTWIGER is an agronomist in 
the USGA Green Section’s Southeastern 
and Florida Regions.

Compaction potential of various roller units can be compared by calculating the roll 
factor, which includes the unit weight, length of the rollers, and the diameter of the 
rollers in the equation.

putting green, there is some amount 
of depression into the putting surface, 
which changes the area of contact. To 
complicate matters, the area of contact 
is not linear but circular, and the weight 
of the unit is not distributed equally 
at all surface points. The amount of 
depression into a green can vary with 
thatch levels, mowing height, soil 
moisture, rootzone construction, and 
other factors. As a result, PSI can be 
extremely variable and difficult to 
determine. In determining PSI, it is 
unlikely that each manufacturer has 
used the same assumptions, leaving 
the superintendent to try and compare 
apples to oranges.

Another popular method of com­
paring rollers is to measure pounds per 
lateral inch. The PLI equation is cal­
culated by dividing the weight of a unit 
by the lateral inches of all the rollers on 
the unit. For example, a roller weigh­
ing 525 pounds with three rollers of 36 
inches each would have the following 
PLI measurement: 525 + (36 x 3) = 8 PLI. 
While this method is certainly easy to 
compute, it does not take into account 
the diameter of the rollers. Theo­
retically, two different models each 
could weigh 525 pounds with three 
rollers 36 inches long, but with different 
roller diameters. In theory, the model 
with the larger roller diameter would 
have a larger area of surface contact 
and would affect the turf differently. By 
not taking roller diameter into account, 
the PLI equation is limited and is not 
a good method to compare rollers.

Introducing the Roll Factor

While neither of the two methods 
above appears to be effective in com­

4

USGA GREEN SECTION RECORD

paring rollers, all hope should not be 
lost. There is a formula called the roll 
factor that can be used effectively to 
compare different pieces of turf equip­
ment, including putting green rollers. 
As we have noted above, the important 
factors to consider when evaluating 
rollers are the weight of the unit, the 
length of the rollers, and the diameter 
of the rollers. The formula for the roll 
factor takes all of these factors into 
account as noted in the following 
formula: Roll Factor = Weight of Unit 
+ (Diameter of Rollers x Length of 
Rollers).

To illustrate how this formula works, 

consider the following example:

Specification

Roller Weight

Number of 
Rollers
Length of 
Rollers
Diameter of 
Rollers
Roll Factor
Formula
Roll Factor 
Value

Roller A

525 lbs.

3

Roller B

750 lbs.

3

36 in.

36 in.

5 in.

8 in.

525
5 x (36 x 3)

750
8 x (36 x 3)

0.97

0.87

In the example, Roller B has a roll 
factor value of 0.87, while Roller A has 
a roll factor value of 0.97. Based on the 
higher roll factor value, Roller A has a 
greater potential for compaction than 
Roller B. Remember that the roll factor 
does not offer a measure of force per 
unit area, but is a method to rank the 
relative potential for compaction of two 
or more rollers. This formula is easy 
to use and all the information needed 
is readily available. By using the roll 
factor, a superintendent has an excel­
lent means to compare rollers and 

WATER QUALITY MONITORING 
AT QUEENSTOWN HARBOR

The results of five years of groundwater monitoring on a golf course 
located in an environmentally sensitive area.

by FRANK WM. “BILL” SHIRK

Bill Shirk, CGCS, takes care of Queenstown Harbor Golf Links, which is located in a critical area, defined as being within 1,000 feet 
of the Chesapeake Bay and its tributaries.

THE CONSTRUCTION of new 

golf courses today requires that 
a maze of environmental regu­
lations be addressed. In areas where the 

quality monitoring often is required. 
Following is the story of the monitoring 
program at the Queenstown Harbor 
Golf Links.

construction and maintenance of golf 
courses potentially could affect surface 
waters or groundwater resources, water 

The story of Queenstown Harbor 
starts at its location. The course is 
situated at the mouth of the Chester 

River and the Little Queenstown 
Creek, less than a mile from the 
Chesapeake Bay. As such, it is desig­
nated as being in a Critical Area of 
Maryland’s tidewater region. A Critical 
Area can be defined as a site that is 
within 1,000 feet of the Chesapeake

JULY/AUGUST 1996

5

TABLEI
Nitrate-Nitrogen Sampling Results at Queenstown Harbor Golf Links (results in mg/1)

B-7

B-8

B-9

B-10

B-12

B-13

B-14

B-15

B-16

All Wells 
Average

Date

11/15/90

03/20/91

05/20/91

09/30/91
04/06/92

06/23/92
10/05/92

01/12/93
03/31/93
06/23/93

10/06/93

01/17/94
04/05/94

06/20/94
10/06/94

Average

B-l

0.02

0.03

0.03
0.02

0.33
0.23
0.35
0.03
0.15

0.08

0.07

0.05
0.10

0.30
0.40

0.15

B-2

0.13

1.60

2.90

0.02

1.80
2.90
1.70

1.40
2.10

2.00

1.70

1.40
1.60

2.10
1.40

1.65

B-4

6.10

8.51
7.90
no sample
7.60

8.10
7.70
11.00
1.90

3.40

5.00

4.30

3.50
4.50

4.90

6.03

B-6

0.02

0.04

0.04
0.05

0.05
0.03

0.01
0.13
0.09

0.05

0.86

0.05

0.10
0.40

0.20

14.00

8.18

7.50
8.62

4.20
8.40
7.70

9.60
5.30

7.90

7.30

3.30
1.90

2.90
2.00

19.00

17.40

15.00

19.00

10.00
23.00
21.00

21.00
18.30

12.70

8.30

16.40
12.50

11.20
14.90

0.14

6.59

15.98

2.60

4.36
6.50

4.81
8.30

8.30
7.10
10.20

6.30
3.50

2.40

1.90
1.30

1.20
0.70

4.63

0.83

8.24
8.90

1.83
11.00

16.00
3.00

9.20
12.10

23.00

4.00

12.50

5.20

5.40
6.10

8.49

no sample
no sample
6.80

0.41
0.40

0.15
0.10

0.51
0.20

0.05

0.05

0.19
no sample
0.40
0.30

no sample
0.05

0.52

0.08
0.05

0.06
0.03
0.02
0.30

1.80

1.30

2.10
0.80

0.80
1.30

6.50
18.30

10.70
6.60

0.80

0.66

10.53

10.00

9.50

7.20
4.40

7.78

1.50

4.00

3.20
2.40

2.78

5.34
5.38

5.61
3.87

4.37

6.72
4.87

6.31
4.67

5.45

3.10

4.63
4.90

3.87
3.51

4.84

Bay and its tributaries. The concern is 
that improper management of Critical 
Area sites could impact the overall 
quality of the Bay waters. Thus, there 
was great concern about the develop­
ment of a golf course near the environ­
mentally sensitive Chesapeake Bay.

The property was owned and 
operated as a working farm for 25 
years by Washington Brick and Terra 
Cotta Company. Prior to breaking 
ground on the construction of a 27- 
hole, upscale, public golf course, the 
approval process consisted of T/i years 
of permitting and 43 public hearings. 
These hearings seemed to be forums for 
change regarding environmental laws 
and, more specifically, the interpreta­
tion of how to define and best preserve 
a wetland. Eventually, the Critical Area 
Commission and the Washington Brick 
and Terra Cotta Company agreed to the 
installation of groundwater monitoring 
stations throughout the property.

Thirteen monitoring wells were in­
stalled using a drilling rig with hollow­
stem augers in July 1990. Installing the 
wells prior to construction provided a 
basis for data comparison. Concentra­
tion data were collected on nitrates, 
phosphates, and other materials within 
the water supply prior to converting 
the land to a golf course.

Finally, Washington Brick and Terra 
Cotta Company broke ground for their 
project on August 1, 1990. The golf 
course lies on a 750-acre tract of land 
that had been used primarily as farm­

6

USGA GREEN SECTION RECORD

land. Hardwood forest, non-tidal wet­
lands, and tidal wetlands present on the 
site were incorporated into the course 
layout. The course was opened for play 
in July 1991. An additional nine holes 
were built in 1994 to complete Queens­
town Harbor Golf Links as a 36-hole, 
upscale, public access golf course.

Environmental Monitoring

The monitoring sites were a critical 
aspect of the golf course development 
project, and their locations were care­
fully determined according to sub­
surface water flow. The quality of 
subsurface water that enters the Chesa­
peake Bay has been and continues to 
be a major concern to people who in­
habit the areas around the Bay. More 
specifically, the potential for nutrient 
loading has been a high-priority issue 
of many environmental groups and 
governmental agencies in this region of 
the country. With the implementation 
of the monitoring program, valuable 
documentation about the effects of 
turfgrass management practices on the 
environment could be collected and 
analyzed. Needless to say, there were 
many questions and a great deal of 
apprehension regarding the conversion 
of agricultural land to a golf course 
facility.

Analysis of the groundwater samples 
is performed by Apogee Research Inc. 
(an independent lab) of Bethesda, 
Maryland, four times per year. Steve 
Roy is in charge of this project. Their 

reports are used to help me better 
manage and adjust our integrated pest 
management (IPM) program. For 
example, adjustments to fertilizer pro­
grams are facilitated by the monitoring 
results.

The agreement specified that the re­
sults of each sampling would be sent to 
the Critical Area Commission, Queen 
Anne’s County Planning Department, 
Washington Brick and Terra Cotta 
Company, in addition to my office. 
The Critical Area Commission has re­
ceived the monitoring data with the 
hope that it will help them decide 
about the future of golf course develop­
ment in Critical Area zones of the 
Chesapeake Bay and its tributaries. For 
that matter, it is hoped that our experi­
ences can help others in the develop­
ment and proper management of a golf 
course in an environmentally sensitive 
area of the country.

On November 15, 1990, nine wells 
were tested for the first time. We now 
have nearly five years of data from 
the original monitoring wells. During 
construction, additional wells were 
installed. The first report and the last 
report will be highlighted in this 
discussion.

November 1990 Test Results

The Federal Drinking Water Purity 
Standard for nitrate-nitrogen is 10 mg/ 
liter (10 ppm). Of the wells sampled, 
two samples (well B-7 and well B-8) 
revealed elevated nitrate levels of 14

mg/1 and 19 mg/1, respectively, (see 
Table 1) on the first sampling date. 
These two wells are located at a 
groundwater discharge point to the 
Chester River and demonstrated the 
significant impact from the previous 
agricultural land use operations. Well 
B-4, located in what is now the practice 
fairway, exhibited a slightly higher 
nitrate level (6.1 mg/1) than the other 
monitoring wells. This specific area was 
also exposed to intense agricultural 
operations prior to conversion to golf 
course turf.

The average concentration of nitrate­
nitrogen from the first sampling date for 
all the wells was 5.34 mg/1. Although 
average concentrations may not tell 
the complete story, the data provided a 
reference point. Well B-l (.02 mg/1) 
represented what is considered to be 
background disturbance as water 
moves onto the site. Phosphorus levels 
for this well (.88 mg/1 total phosphorus 
and 4.10 mg/1 orthophosphate) were 
quite high. Again, these levels may be 
indicative of how agricultural land use 
can affect groundwater.

During the initial testing prior to any 
applications to the golf course, three 
wells (B-l, B-7, and B-10) showed con­
tamination. The pesticides included: 
carbofuran (Furadan) and carbaryl 
(Sevin), commonly used agricultural in­
secticides; pendimethalin and atrazine, 
commonly used herbicides (pre-emer- 
gent); and the fungicides chlorothalonil 
and iprodione. All samples provided re­
sults below analytical detection levels. 
Nevertheless, trace activity was ob­
served, which provided important 
reference data regarding the trends of

Wetlands and environmentally sensitive habitat areas are designated as protected 
areas throughout the entire golf course property.

Areas between the golf course and the Chesapeake Bay water were established as low-maintenance and naturalized buffer areas.

the water quality prior to and during 
construction, and after grassing the golf 
course (Table 2).

October 1994 Test Results

After nearly five years of testing, 
nitrate-nitrogen concentrations are the 
primary area of concern. Data collected 
on all other nutrients and pesticides 
have produced results that are classified 
as analytically undetectable. The fact 
that nutrient and pesticide concentra­
tions in the groundwater supplies have 
dropped from their pre-golf course 
levels demonstrates that a well-man- 
aged golf course can protect and even 
enhance water quality compared to 
other common land uses. Groundwater 
samples continue to be analyzed for 
nitrate-nitrogen, primarily for two 
reasons:

1. to continue to monitor potential 
nutrient loading of the Chesapeake 
Bay, in particular nitrogen, and

2. to determine the usefulness of 
nitrate-nitrogen as an indicator of 
groundwater quality conditions and 
to study its movement.

The average nitrate-nitrogen concen­
tration of all the wells has fallen since 
the testing program was implemented. 

The average concentration from all 
wells decreased from the 5.34 mg/1 
determined in November 1990. This 
decrease represents a 35% drop in the 
average nitrate concentrations within 
the water across all the wells. Despite 
minor fluctuations that have occurred 
over time, the phosphate levels con­
tinue to drop, and one well, B-8, has 
had elevated nitrate-nitrogen concen­
trations above the drinking water 
standard (Table 1). This well is located 
next to an active farm. We speculate 
that since the implementation of the 
well water testing program, com, soy­
beans, and wheat crops have been 
grown and harvested from the adjacent 
parcel, perhaps contributing to the 
elevated nitrate levels.

Wells that had previously been above 
10 mg/1 (B-7, B-14, B-15) have shown 
steady improvement, all dropping 
below the water purity standard. The 
testing at well sites B-14, B-15, and 
B-16 began in 1994. The land was 
aggressively farmed until the fall of 
1993. This area was developed into 
an additional nine golf holes, and we 
believe the test results for these wells 
will show a decline in the nitrate levels 
similar to the other monitoring sites.

In August 1995, members of the 
Maryland Senate Economic and En­
vironmental Affairs Committee toured 
Queenstown Harbor Golf Links. The 
tour provided an opportunity to demon­
strate the technology being used to 
manage our golf course turf. Important 
information was provided for legislators 
that will help them make future de­
cisions about golf course issues. More 
importantly, the legislators learned that 
integrated pest management programs 
that contain best management prac­
tices can be used to operate a golf 
course located in a critical area in a 
responsible manner.

It took a lot of effort and expense to 
get us to this point. The staff at the 
Queenstown Harbor Golf Links be­
lieve our efforts have contributed to a 
better understanding that properly 
maintained turfgrass can have a posi­
tive impact on the environment. Golf­
ers, non-golfers, and the area’s wildlife 
are co-existing nicely with the Chesa­
peake Bay and its tributaries.

BILL SHIRK, CGCS, is the golf course 
superintendent at Queenstown Harbor Golf 
Links, located in Queenstown, Maryland.

TABLE 2
Queenstown Harbor Golf Links — Water Quality Laboratory Report (Sampling Date: 11/15/90)

Sample ID

Chemical 
(mg/1)

Nitrate 
Nitrogen

Ammonia 
Nitrogen

Kjeldahl 
Nitrogen

Phosphorus 
(total)

Orthophosphate 
Phosphorus

Carbofuran 
(PPb)

Carbaryl 
(PPb)

Prowl 
(PPb)

Chlorothalonil 
(PPb)

Iprodione 
(PPb)

Atrazine 
(PPb)

<2.00 <2.00 <2.00 <0.05

<0.10 <2.00

<2.00 <2.00 <2.00 <0.05

<0.10 <2.00

<2.00 <2.00 <2.00 <0.05

<0.10 <2.00

B-l
B-2

B-4
B-7
B-6

B-8

B-9
B-10

0.02
0.90
0.13
1.10
6.10
0.20
14.00
0.60
0.02 <0.10
19.00 <0.10
2.60
0.83

0.10
<0.10

9.80
12.00
18.00

0.60
<0.10

9.10

3.70
1.80

0.88
0.05

0.24
0.52

0.20
0.05
0.02

0.02

LQC-1 (Little Queenstown Creek)
CR-B-7 (Chester River)

0.46

0.39

Feet:

B-l

B-2

B-4

B-6
B-7

B-8

B-9
B-10
B-12

Depth to
Bottom

17.00

16.50

16.00
14.00

16.00
20.00
20.00
22.00
16.50

Tape to Water level
Water

on Tape

Depth to
Water

Top Casing

7.00

11.50

13.00

12.20
9.00

14.50
10.50
16.00
11.00

1.09

0.99

0.94

1.54
1.38
0.95
0.45
0.96
0.58

5.91

10.51
12.06

10.66
7.62

13.55
10.05

15.04
10.42

17.28

21.41
20.30

19.90
8.69

19.94
21.53
24.31
22.85

8

USGA GREEN SECTION RECORD

4.10
< 0.01
<0.01
<0.01
<0.01

<0.01
<0.01

<0.01

Water
Level

11.37

10.90

8.24

9.24
1.07

6.39
11.48
9.27

12.43

Optimizing The Turf grass 
Canopy Environment With Fans

Fans can help overcome poor growing environments.

by PATRICK M. O’BRIEN

ALTHOUGH most people in the 
ZJk turf industry have seen electric 
Z X or gas-powered fans used on 
the golf course, the rationale for 
their use often is misunderstood. As 
an agronomist for the USGA Green 
Section, I am frequently asked ques­
tions about the use of fans. To help 
those involved with this issue, a dis­
cussion of the benefits and liabilities of 
the use of fans is presented.

Affect on the Health of 
Bentgrass Putting Greens

Years of experience have shown that 
golf superintendents have the most 
trouble growing bentgrass or Poa 
annua greens during the summer at a 
site surrounded by trees or other bar­
riers that allow almost no air move­
ment. A USGA-type green provides a 
very effective base for growing putting 
green turf, but it cannot compensate for 
the lack of air circulation. In this envi­
ronment, disease and higher rootzone 
moisture associated with these areas 
cause turfgrass plants to decline. Fans 
help improve air flow across greens, 
and the survival of bentgrass has been 
shown by Taylor to improve at sites 
with the increased air movement pro­
vided by fans.1 The positive effects of 
fans drying out the soil and increasing 
evapotranspiration are the two major 
benefits influencing the bentgrass. Fans 
offer little cooling benefit to the turf­
grass, which is contrary to most 
popular opinion.

Fans are sometimes 
mounted in trees 
instead of using poles.

$ < w

Gas-powered fans can be used as a last resort in sites not located in close proximity to 
an electrical source, but they require intensive labor to operate.

Which Greens Need Fans?

Fans should be specifically used to 
help improve turf quality at problem 
green sites. By far the most popular use 
of fans is at boxed or pocketed sites 
surrounded by trees or other features 
that restrict air movement. In the past, 
these sites have been more prone to 
summer decline caused by disease, 
excess moisture, and surface algae. 
Green sites with wet rootzones also 
benefit from a fan program. Even small 
problem areas at open sites can benefit 
from the use of fans directed to the 
specific problem area.

Placement of the Fans

Most superintendents place two 
stationary fans at the 10 and 2 o’clock 
positions at the rear of the green, 
approximately 15 to 30 feet from the 
edge of the green. Fan height above the 
green surface normally is 10 feet or less 
with these stationary fans. Most fan 
companies sell poles that are usually 
seven feet tall, since OSHA requires 

10 USGA GREEN SECTION RECORD

finger guards on any fans positioned 
at lower heights. Finger guards can 
restrict air flow distance by up to 12%. 
Hand guards, which restrict air flow 
less than finger guards, are required for 
fans on poles taller than 7 feet. Trees 
are sometimes used instead of a poles, 
if available.

The key is to position the fan as 
close to a green and as low to the 
ground as possible to generate maxi­
mum air flow across the green surface. 
The main goal is to achieve a 3- to 
4-mph wind speed over the turfgrass 
canopy. If fans are too far away or 
elevated too high, wind speed power 
will be lost by deflection off the grass 
itself, or by natural friction loss. A 
Turbometer, which costs about $120, 
is an effective instrument to help 
determine fan placement at each site. 
The Turbometer should be set on the 
green surface during measurements, 
and with the fans running, check 
various areas around the green for 
the 3- to 4-mph wind speed.

Another popular method to help 
determine fan location is the use of 
engineering flags. On a calm morning, 
place engineering flags over the green 
surface at 3- to 5-foot intervals with 
the flag height at approximately 3 
inches above the ground. Clipping the 
metal pole on the engineering flags to 
a 3-inch length will speed this step. 
Turn the fans on and adjust the fan 
position until most of the flags are 
waving. Other superintendents check 
fan position by igniting smoke bombs 
at several sites on a green to detect air 
movement.

When to Operate

Golf superintendents need to pay 
attention to fan schedules, since each 
site may have different requirements. 
Fans usually run 24 hours per day at 
green sites that hold soil moisture and 
at pocketed areas. Running fans from 
early to mid morning to the early eve­
ning is advised at the small problem 
sites on certain greens. Other sites may 

require fan usage only during the early 
morning to mid morning when dew 
and surface moisture are greatest. In 
the Southeastern Region, surface mois­
ture also can come out of the rootzone 
during the daylight hours, even at times 
of very high humidity. Fan use seldom 
will be required at open-air sites on 
sunny days with low humidity.

Fan Types

Nearly all fan types commonly seen 
have done a good job when positioned 
and run properly. Caged, oscillating, or 
turbo fans are the most common types 
observed. Oscillating fans are by far 
the most popular at golf courses. In the 
past, fan oscillating motors have caused 
problems, but today oscillating motors 
have improved power, similar to the 
other fan motors. Fan diameters can 
range from 22 to 48 inches. Because 
most fans are stationary to poles 
elevated above the greens, fan diameter 
size has been increasing with the 
demand for additional air movement 
from these products. Many fans now 
can throw a column of air more than 
200 feet. With the improved power of 
many fans, some air movement can 
occur even at areas where the fan is 
not directed. Stationary fans do have 
the potential to dry the turf, since wind 
speeds can be much higher than 3 to 4 
mph next to the fan. Extra irrigation 
may be needed for the turf in some 
situations when these fans are used.

Portable or floating fans are also 
popular, and most courses have at least 
two available. Most portable fans are 
the 48-inch cage types. A combination 
of both permanent and portable fans 
is a plus at some problem greens. 
Portable fans are used to treat special 
areas that require extra air circulation, 
such as a wet soil condition. Many 
superintendents move these floating 
fans to problem sites late in the evening 
and allow them to run all night. The 
fans can be positioned right next to 
the green during the night to provide an 
extra “blast” of air without affecting 
golfers. The portable fans can be repo­
sitioned and moved further away from 
the green the next morning, especially 
taking into consideration the hole 
location for that day. The additional 
air movement and mixing from this 
fan, especially when combined with the 
prevailing wind and the permanent 
fans, promotes faster drying. Portable 
fans can also be used at the main­
tenance building to help cool the 
mechanic’s working area on hot days.

Tips on Installation

Setting up the electrical system for 
the fans on an existing golf course is 
very difficult, so a certified electrician 
should do all electrical work. Unfor­
tunately, the electrical wire at the 
irrigation control boxes is too small 
for the high current requirements of 
electric fan motors, so alternative 
power supplies are needed. Usually, 
water coolers, irrigation pump houses, 
lift pumps, bathrooms, maintenance 
buildings, and clubhouses are sources 
of electrical power. Often, sites with 
fans are not close to any of these 

sources, and new meter service then 
is the only option. Gas generators are 
a last resort, with the inconvenience of 
refilling the generator with gas, trans­
portation requirements, and the extra 
noise. New golf courses should initially 
install larger wire coming into the irri­
gation control boxes so that if electricity 
is required later for fans, the larger wire 
can handle the additional amperage 
for a fan motor.

Most fans used today have single­
phase motors, although three-phase 
motors are preferred because of their 
higher power efficiency. Smaller wire 

Extension cords and above-ground wiring should be avoided wherever possible.

JULY/AUGUST1996 

11

can be used for three-phase motors, 
resulting in a lower initial installation 
cost. Many water coolers, irrigation 
and lift stations, and clubhouses have 
three-phase power for fans near these 
sites. Sometimes step-down trans­
formers are needed, especially for the 
oscillating motor, which is always 
single-phase power, and luckily these 
transformers usually cost just $30.

All new electrical equipment and 
service must meet the local codes. 
Tables are available to calculate the 
wire size needed based on the distance 
from the power sources to the fan and 
the resistance loss in the wire. Direct 
burial cable wire (usually #4 or #6 
cable) normally is pulled into the 
ground with a vibratory plow on a 
ditch-witch trencher with minimal dis­
turbance to the surface, although occa­
sionally small trenches are made to 
insert the wire. Wire depths vary 
according to the local codes, but most 
installations require an 18- to 24-inch 
depth. Wire is sometimes placed in a 
plastic conduit (depending on the 
local codes) under cart paths and 
service roads and across bridges for 
additional protection. Avoid the use of 
junction boxes whenever possible, as 
they could become sources of prob­
lems later.

At the green installation site, the 
wires, switches, timers, and plugs 
usually are placed in a sealed irrigation 
valve box with drainage. Avoid wiring 
the fan directly, as removing the fan 
later with this type of connection 
system is more difficult. Installing an 
extra plug to power a portable fan that 
may be needed later is always a plus, 
but a larger size wire will be needed 
initially to handle this extra power re­
quirement. Timers also can be installed 
in the valve box to vary the operation 
of the fans. At The Honors Club, 
course superintendent David Stone 
has even connected his fans to the 
irrigation radio controllers. A switch 
to turn the fan off and on is another 
plus. It is always a good idea to install 
a ground fault interrupter at the plug 
to act as circuit breaker to enhance 
the safety of maintenance workers and 
golfers. Circuit breakers at the meter 
also help to avoid electrocution con­
cerns. Afterwards, have an inspector 
check all electrical work to insure that 
all local codes are met.

Costs

The Turbometer is one tool that can be 
used to help determine fan locations 
around a green.

States. Obviously, operation time will 
vary depending on the location of 
the golf course and the weather each 
summer. Most utility companies offer 
seasonal or full-time service for these 
meters. Flexible programs depending 
on the projected power consumption 
and usage are offered by many power 
companies, and consultants can detail 
your options. Most superintendents 
report typical electrical power costs for 
running two fans at a green site average 
between $75 and $100 per month.

Fan Maintenance

Fans have required very little pre­
ventive maintenance so far on golf 
courses. Rust spots and scratches will 
occur over time just from being outside. 
A few fan distributors even offer annual 
maintenance services to wax and paint 
fans, but so far very few customers have 
taken advantage of this service. Most 
superintendents bring the fans inside 
the maintenance building or into a pole 
bam for the winter months. In any 
case, the structure must be tall enough 
so the fans can be stored in an erect 
position so moisture cannot enter the 
fan motor. Pole fans are easily discon­
nected by unscrewing the poles from 
their stands. The outside electrical 
components are protected by capping 
the plastic storage box. Some superin­
tendents prefer to leave the fans at 
their permanent sites, especially if not 
enough storage space is available at 
the maintenance area. Heavy-duty 
fan covers that will not tear or blow 
away are now available from most 
distributors.

home sites near some of their greens 
today, and some residents maybe close 
enough to hear the fan motor noise. 
Educating your neighbors about the 
importance of the fans is essential for 
the superintendent. Letters sent to 
these homeowners each spring dis­
cussing the agronomic value and fan 
operational hours may help reduce 
complaints.

Effects on the Rules of Golf

Fans do have an impact on the 
Rules of Golf, depending on whether 
they are permanently or temporarily 
installed. Any time fans are installed 
in a permanent base, the golfer can 
assume the fan won’t be moved. Perma­
nently positioned fans are considered 
immovable obstructions according to 
the Rules of Golf. If the fan interferes 
with the lie of the golf ball or the 
swing or stance of the golfer, relief is 
provided under Rule 24-2. Sometimes 
the fan may be found between the golf 
ball and the hole location. Under this 
Rule, line-of-sight relief is not provided 
for with permanently installed fans, 
and the ball must be played as it lies.

Fans that have been set up on a 
temporary basis are treated as tempo­
rary immovable obstructions. Interven­
tion on the golfer’s line of play would 
warrant relief.

If a golf ball deflects off a fan, it is 
a rub of the green and the golfer plays 
the ball where it lies. If a fan deflects a 
golf ball out-of-bounds, the golf ball is 
still considered out-of-bounds.

Conclusion

Fans have made a major impact on 
many golf courses by helping the turf 
survive where it previously had died 
each summer. Many golfers also enjoy 
the additional comfort of a cool breeze 
while putting. However, sometimes 
fans are a nuisance to golfers because 
of the extra noise and their impact on 
the Rules of Golf. These negative 
factors must be weighed against the 
gain of improved health and playability 
of putting green turf.

’Gene Rupert Taylor II. 1995. The Effects 
of Mechanically Induced Air Movement on 
the Temperature, Water Potential and Soil 
Moisture Percentage of Creeping Bentgrass 
(Agrostis stolinifera L.) Golf Greens. MS 
Thesis, North Carolina University.

Fans are used most during the 
months of May through September in 
the southern portion of the United

Noise

The auditory effects of fans are also 
a consideration. Most courses have 

PATRICK O’BRIEN is director of the 
USGA Green Section’s Southeastern 
Region.

12 USGA GREEN SECTION RECORD

A USGA-SPONSORED RESEARCH PROJECT

Physiological Management of 
Bipolaris sorokiniana Leaf Spot Symptom 
Expression by Kentucky Bluegrass

A unique approach to disease management that 
involves suppression of visual symptoms.

by DR. CLINTON F. HODGES

Bipolaris sorokiniana in­

fects grasses throughout the 
1 temperate regions of the world. 
Among the grass species used for turf, 

B. sorokiniana is best known for 
causing a leaf spot of Kentucky blue­
grass (7, 24). It also can damage creep­
ing bentgrass, perennial rye, and red 
fescue. In addition to causing leaf spot, 
B. sorokiniana can infect crowns, 
rhizomes, stolons, roots, and inflores­
cences of turfgrass plants.

The leaf spot disease caused by B. 
sorokiniana is often referred to as 
spring leaf spot in turf disease text­
books (24). Leaf spot is commonly 
observed in the spring, but damage to 
leaves can be more extensive in the 
fall, especially with wet, moderately 
cool, overcast conditions (19, 20, 21, 
23). The spots produced on the leaves 
of Kentucky bluegrass are initially dark 
brown, to deep purple, to almost black 
in coloration. Spots occur individually 
or are scattered over the surface of in­
fected leaf blades. As the individual 
spots enlarge, their centers typically 
become tan-colored and they often 
are surrounded by a chlorotic halo. If 
large numbers of spots occur on a 
single leaf, they often coalesce and 
cause rapid blighting of the leaf. Fewer 
spots on a leaf results in a progressive 
yellowing of the entire leaf blade. Yel­
lowing of infected leaves occurs in the 
early spring, but it is the dominant 
symptom in fall and early winter.

Control of leaf spot (and the other 
diseases caused by this pathogen) can 
be difficult. The resistance shown by 
Kentucky bluegrass cultivars is not 
very reliable and generally breaks down 
under cultural and environmental 
stresses (12,23, 24). Several fungicides 
are effective against B. sorokiniana 
(24), but to be most effective they must 
be on or in the plants before infections 
are initiated. Once leaf spot has been 
initiated (and other organs of the plant 
also are infected), chemical control 
often is ineffective due to the inaccessi­
bility of the fungicides to infected 
crowns, rhizomes, and roots (23). 
Hence, when Kentucky bluegrass is 
severely leaf-spotted, very large areas of 
turf become yellowed and the quality 
of the grass becomes aesthetically un­
acceptable. If the condition persists 
throughout the growing season, or 
from season to season, the turf will 
progressively thin and large areas can 
be completely lost.

Developmental Physiology 
of Leaf Spot

Control of leaf spot by means of 
cultural practices, host plant resistance, 
and fungicides is difficult and expensive 
under the best of circumstances. Be­
cause of the difficulty of controlling leaf 
spot and the prevalence of the disease 
in the north central states, studies on 
the developmental physiology of leaf 
spot of Kentucky bluegrass have been 

an ongoing part of the turf disease 
program at Iowa State University for a 
number of years. The ultimate purpose 
of this research has been to determine 
the physiology of disease development 
and to develop new approaches to the 
control and/or management of the 
disease.

The most damaging developmental 
characteristic of leaf spot is the yellow­
ing of infected leaves that decreases the 
aesthetic value of the turf. Research 
conducted in our laboratory has shown 
that the yellowing of infected leaves is 
related to light, senescence processes, 
hormone action, and a phytotoxin pro­
duced by the pathogen. The yellowing 
of infected leaves can also be enhanced 
by postemergence herbicides.

Light and Senescence: The severity 
of yellowing by leaf-spot infected leaves 
typically increases with the aging of the 
individual leaves. This developmental 
characteristic of leaf spot is substan­
tially influenced by photoperiod. As 
daylength increases from 10 to 14 
hours, the size of the leaf spots and 
the yellowing of infected leaves de­
creases (18, 21). Infected leaves sub­
jected to continuous dark for 96 hours 
will have up to 70% of the leaf tissue 
turn yellow; infected leaves subjected 
to continuous light show yellowing of 
only 9% of the leaf tissue. These obser­
vations explain in part why leaf spot 
becomes less severe from spring to 
summer as daylength increases. It also 

JULY/AUGUST1996 

13

provides part of the evidence for why 
this disease is potentially more impor­
tant in the fall (with progressively 
shorter daylengths) than in the spring.
Daylength also interacts with the 
natural senescence processes of leaves 
to further enhance yellowing of in­
fected leaves. When progressively older 
infected leaves are subjected to a 
natural light spectrum with a daylength 
of 14 hours, there is little difference in 
the yellowing of leaves of different ages. 
When the infected leaves of different 
ages are subjected to 10- or 14-hour 
daylengths, yellowing of the two 
youngest leaves does not differ, but the 
two oldest infected leaves subjected to 
the 10-hour daylength show substantial 
yellowing (20). These responses imply 
an interaction between photoperiod 
and leaf senescence that influences 
severity of leaf spot development and 
subsequent yellowing of infected 
leaves. Long daylengths (14 hours or 
more) delay senescence and the yel­
lowing of infected leaves. Short day­
lengths (10 hours or less) promote leaf 
senescence, especially among older 
leaves, and this condition is exploited 
by the pathogen to increase the severity 
of yellowing.

This light phenomenon is further 
illustrated by increasing the amount 
of far-red light in the light spectrum. 
Far-red light is known to promote 
senescence processes, and it will in­
crease the severity of yellowing by in­
fected leaves irrespective of daylength 
(20). The older leaves of the shoot that 
are beginning to senesce are especially 
sensitive to far-red light. As light passes 
through the upper, younger leaves of 
the shoot, the proportion of far-red 
light striking older undercover leaves 
increases and further enhances the 
yellowing associated with infected 
leaves. The effect of far-red light com­
bined with the senescence-promoting 
effect of short daylength in the fall 
further predisposes infected leaves to 
accelerated yellowing.

Hormones: The interaction between 
photoperiod, light quality, and senes­
cence implies that hormones are 
involved in the yellowing of infected 
leaves. The first evidence of this came 
from studies on the effect of postemer­
gence herbicides on leaf spot develop­
ment. Applications of 2,4-D, MCPP, or 
dicamba to Kentucky bluegrass were 
found to substantially increase the 
yellowing of leaf-spot-infected leaves 
(8). It was further observed that the 
herbicides increased the severity of 
yellowing on each older infected leaf 

14 USGA GREEN SECTION RECORD

(9, 10). These postemergence herbi­
cides are auxin-type growth regulators. 
One of the side effects of auxin-type 
herbicides in perennial grasses and 
other plant species is that they elicit the 
production of the hormone ethylene by 
the plant, and the increase in ethylene 
can enhance the rate of senescence in 
mature tissues (1). This enhanced 
senescence caused by the herbicide­
generated ethylene is exploited by the 
pathogen, and the yellowing of older 
infected leaves is further enhanced.

The potential involvement of ethylene 
in the yellowing of leaf-spot-infected 
leaves of Kentucky bluegrass provided 
the first critical information on the 
physiology of the disease that could 
be tested experimentally. During the 
infection of Kentucky bluegrass leaves 
by B. sorokiniana, studies revealed 
that substantial quantities of ethylene 
were produced in the leaves and that 
the increase in ethylene was correlated 
with the yellowing of infected leaves 
(15, 18). Natural levels of ethylene in 
leaves of Kentucky bluegrass range 
from about 250 to 350 ppb. The 
ethylene content of leaves infected by 
B. sorokiniana increases to 2,400 ppb 
or higher within 48 to 72 hours after 
infection and then progressively de­
clines as the disease progresses. Visible 
yellowing of infected leaves can be 
seen within 24 hours of peak ethylene 
production. The severity of the yellow­
ing increases on each older infected 
leaf, illustrating the link between the 
ethylene surge and leaf senescence 
(11).

Although a good cause-and-effect 
correlation was developed between the 
rise in ethylene and the subsequent 
yellowing of infected leaves, proof that 
the ethylene was responsible for the 
yellowing of infected leaves was still 
needed. Ethylene, as a plant hormone, 
is unique because it is a gaseous sub­
stance. This characteristic permits the 
ethylene to be evacuated from the leaf 
tissue during the infection process by 
placing the leaves of intact plants under 
a vacuum. When ethylene is evacuated 
from infected leaves, the leaf spots 
develop normally, but about 80% of the 
chlorophyll is retained by the infected 
leaves and they remain visibly green 
(15). In other studies in which plants 
were treated with norbornadiene 
(NBD), a substance known to block 
the mode of action of ethylene, infected 
leaves retained over 90% of their 
chlorophyll while the leaf spots devel­
oped normally (11). These studies 
clearly established ethylene as the pri-

Development of Bipolaris sorokiniana 
on Kentucky bluegrass leaves results in 
yellowing 96 hours after inoculation.

mary cause of yellowing of leaf-spot- 
infected leaves.

Phytotoxins: When ethylene is 
evacuated from infected leaves, or its 
mode of action is interrupted by NBD, 
there is still a 10% to 20% loss of 
chlorophyll from the leaves. This loss 
seems to be associated with the 
chlorotic halo surrounding individual 
leaf spots on the leaves. Development 
of chlorotic halos is not prevented by 
the control of ethylene action. It is 
believed that the halos are the result 
of direct injury by a nonspecific phyto­
toxin (helminthosporal or prehel- 
minthosporol) produced by B. soro­
kiniana during the infection process 
(4,25,26). The phytotoxin functions by 
disruption of cell membranes.

The Potential for Management 
of Symptom Expression

The establishment of ethylene as a 
primary cause of yellowing of leaf-spot- 
infected leaves provided an opportunity 
to develop a new approach to the 
management of this disease. The tradi­
tional approaches to disease control are 
development of plant resistance and/or 
prevention of infection by means of 
fungicides. Both approaches have sub­
stantial limitations for the control of

sary to return to ethylene and its bio­
synthesis during the infection process.

Potential for Chemical Management 
of Symptom Expression

Studies were initiated in 1991 to 
determine if ethylene biosynthesis 
could be reduced or prevented in leaves 
infected by B. sorokiniana, and there­
by prevent a substantial portion of the 
yellowing of infected leaves. The 
ethylene generated during infection is 
produced primarily by the host plant 
in response to the infection (22), with 
relatively small amounts coming from 
the pathogen (5,6). The biosynthesis of 
ethylene in infected leaves is as follows: 
methionine (Met) S-adenosyl-L- 
methionine (AdoMet) 1-amino- 
cyclopropane-l-carboxylic acid (ACC) 
ethylene (27). The conversion of 
AdoMet to ACC is mediated by the 
enzyme ACC synthase (2). This enzyme 
can be inhibited by a number of com­
pounds that prevent the biosynthesis 
of ethylene (3, 17), but prior to our 
studies, none of the substances had 
been evaluated for their ability to 
prevent ethylene biosynthesis in a host­
pathogen interaction.

Our initial studies evaluated two 
known enzyme inhibitors (aminooxy)- 
acetic acid (AOA) and canaline (CAN) 
by applying them to the soil in which 
Kentucky bluegrass plants were grow­
ing (13). Infection of leaves on treated 
and nontreated plants did not differ, 
but infected leaves of nontreated plants 
produced 1,476 ppb ethylene within 48 
hours. The leaves of plants treated with 
AOA or CAN produced 700 and 950 
ppb of ethylene in response to infec­
tion, respectively. The infected leaves of 
AOA-treated plants retained 80% of 
their chlorophyll and the CAN-treated 
plants 74%. These values represent 
substantial increases in chlorophyll re­
tention (and prevention of yellowing) 
compared to the 43% chlorophyll re­
tention in the nontreated, infected 
leaves.

More recent studies with CAN applied 
directly to the leaves of Kentucky blue­
grass held the ethylene surge to about 
850 ppb without interfering with in­
fection, and the infected leaves retained 
90% of their chlorophyll (14). A 90% 
retention of chlorophyll during disease 
development keeps the infected leaves 
green with only the brown lesions 
present. These studies demonstrated 
that the yellowing of leaf-spotted leaves 
could be physiologically managed 
without preventing infection and leaf­
spot development on the leaves.

Several questions still remain unan­
swered relative to management of the 
yellowing of leaf-spotted leaves. It is 
still unclear as to how effective chemi­
cal treatments will be on senescing 
leaves. Studies are in progress to 
determine the ability of CAN (and 
other substances) to slow or prevent 
yellowing on the oldest infected leaves 
of the shoot. Also, the compounds 
worked with to date (CAN, AOA) 
would not be effective for field use 
because of toxicological problems, but 
other substances and treatment tech­
niques are still under study. Develop­
ment of a practical field control tech­
nology is not out of the realm of 
possibility. Overall, the control of 
yellowing of leaf-spot-infected leaves 
with CAN and AOA has been effective 
and suggests that physiological man­
agement of the yellowing symptom is 
possible.

Management of ethylene biosyn­
thesis might also have some unforeseen 
benefits in addition to controlling the 
yellowing of leaf-spotted leaves. Since 
ethylene is a known promoter of 
senescence, reducing the levels of 
ethylene in the plant might prolong 
the life of aging leaves. By slowing the 
aging of leaves, the yellowing of in­
fected leaves might be further reduced 
and infection by secondary pathogens 
and saprophytes also decreased. Con­
trolling symptom expression, as op­
posed to infection, might also slow the 
natural selection processes of the 
pathogen. If the pathogen is permitted 
to infect and develop normally, the 
need for it to change genetically in 
order to overcome a fungicide or plant 
resistance would be greatly diminished.

Potential for Genetic Management 
of Symptom Expression

Blockage of ethylene biosynthesis 
by means of exogenous application of 
chemical inhibitors to leaf-spot-in­
fected leaves of Kentucky bluegrass can 
substantially decrease the yellowing of 
infected leaves. Continued research on 
this approach could result in a practi­
cal chemical treatment for control of 
symptom expression; however, devel­
opment of a safe chemical treatment 
system could be a long process. A non­
chemical solution to the control of 
symptom expression would be environ­
mentally more acceptable and is within 
the realm of possibility.

Discovery of the gene for the enzyme 
ACC deaminase (16), which regulates 
the availability of ACC for ethylene 
biosynthesis, may provide the most 

JULY/AUGUST1996 

15

Leaves treated with canaline (CAN) to 
prevent the biosynthesis of ethylene by 
the plant during infection affects the 
development of Bipolaris sorokiniana.

diseases induced by B. sorokiniana. 
However, with increasing knowledge 
of the physiology of leaf spot develop­
ment, it may be possible to prevent the 
yellowing of infected leaves without 
preventing infection. If the yellowing 
of leaf-spot-infected leaves could be 
prevented, the presence of small leaf 
spots would be of little consequence to 
the aesthetic value of the turf, and the 
diseased leaves would be periodically 
mowed off. Development of a system 
for management of symptom expres­
sion (specifically the yellowing of in­
fected leaves) could provide a new ap­
proach to leaf spot management that 
could compliment, or replace, present 
systems that rely solely on prevention 
of infection.

There are two possible approaches 
to how management of symptom ex­
pression by leaf-spot-infected leaves 
might be accomplished. One approach 
involves the chemical inhibition of 
ethylene biosynthesis, or its mode of 
action, during the infection of the 
leaves. The second approach involves 
the regulation of ethylene biosynthesis 
during infection by means of genetic 
modification of the plant. To under­
stand the work we have conducted to 
date on these approaches, it is neces­

expedient approach to genetic control 
of ethylene biosynthesis by infected 
leaves. The enzyme degrades ACC and 
prevents it from forming ethylene. The 
by-products of ACC degradation are 
metabolized to amino acids commonly 
found in higher plants. The ACC 
deaminase gene has been introduced 
into tomatoes, where it effectively de­
creases ethylene biosynthesis, but the 
gene has not been established in a 
perennial grass.

Research is in progress to determine 
whether the deaminase gene can be 
established in Kentucky bluegrass. The 
process of establishing the gene in 
Kentucky bluegrass first necessitates 
establishing cells of the plant in callus 
culture. This process has been achieved 
and whole plants have been success­
fully regenerated from the callus. It now 
remains to be determined if the ACC 
deaminase gene, which originates from 
a Pseudomonas bacterium, can be 
established in the Kentucky bluegrass 
callus, and if the gene will be incorpo­
rated into the cells of plants regener­
ated from the callus cells. Lastly, if the 
gene is incorporated into the regener­
ated plants, will it control the ethylene 
surge during infection and decrease the 
yellowing of the leaves?

The outlook for sucessfully estab­
lishing the ACC deaminase gene in 
Kentucky bluegrass is guardedly opti­
mistic. It has been determined that like 
infected leaves, Kentucky bluegrass 
callus cultures inoculated with B. 
sorokiniana generate ethylene. If the 
gene can be incorporated into the 
callus cells, a callus bioassay system 
could be developed for determining 
the effectiveness of the gene for control­
ling ethylene prior to regenerating 
whole plants. Work is presently in 
progress for introducing the ACC 
deaminase gene into Kentucky blue­
grass callus. A DNA vector is being 
constructed that will include the ACC 
deaminase gene, and the vector will 
be attached to another gene that is 
specific for expression in grasses. The 
vector will then be introduced to the 
callus cells by means of a particle gun.
The research conducted over many 
years on the physiology of leaf spot 
symptom expression by Kentucky 
bluegrass has provided information 
that will be effectively used in develop­
ment of new disease management 
strategies. The knowledge gained rela­
tive to photoperiod, light quality, hor­
mones, phytotoxins, and postemer­
gence herbicides has provided the 
foundation for exploration of radically 

16 

USGA GREEN SECTION RECORD

different approaches to the manage­
ment of B. sorokiniana leaf spot 
(and perhaps some other leaf-infecting 
pathogens). Prevention of ethylene bio­
synthesis and yellowing of Kentucky 
bluegrass leaves in response to infec­
tion by B. sorokiniana by means of 
chemical treatment or genetic altera­
tion is feasible. Whether this approach 
succeeds or fails, the knowledge gained 
on how the symptoms are produced 
has opened the door to an unlimited 
number of possibilities that will ulti­
mately alter how we approach the 
management of many turfgrass 
diseases.

Acknowledgement

I wish to thank the United States 
Golf Association Green Section for 
providing a grant in support of portions 
of the research presented in this article.

DR. CLINT HODGES is a professor in the 
Department of Horticulture at Iowa State 
University, Ames, Iowa.

References

1. Abeles, E B. 1968. Herbicide-induced ethylene 
production: role of the gas in sublethal doses of 
2,4-D. Weed Sci. 16:498-500.

2. Adams, D. O., and Yang, S. F. 1979. Ethylene 
biosynthesis: Identification of 1-aminocyclopro- 
pane-l-carboxylic acid as an intermediate in the 
conversion of methionine to ethylene. Proc. Natl. 
Acad. Sci. U.S.A. 76:170-174.

3. Amrhein, N., and Wenker, D. 1979. Novel 
inhibitors of ethylene production in higher 
plants. Plant and Cell Physiol. 20:1635-1642.

4. Carlson, H., Nilsson, P., Jansson, H. -B., and 
Odham, G. 1991. Characterization and determi­
nation of Prehelminthosporal, a toxin from the 
plant pathogenic fungus Bipolaris sorokiniana, 
using liquid chromatography/mass spectrometry. 
J. Microbiol. Meth. 13:259-269.

5. Coleman, L. W, and Hodges, C. F. 1986. The 
effect of methionine on ethylene and 1-amino- 
cyclopropane-l-carboxylic acid production by 
Bipolaris sorokiniana. Phytopathology 76:851- 
855.

6. Coleman, L. W, and Hodges, C. F. 1987. 
Ethylene biosynthesis in Poa pratensis leaves in 
response to injury or infection by Bipolaris 
sorokiniana. Phytopathology 77:1280-1283.

7. Couch, H. B. 1973. Diseases of Turfgrasses. 2nd 
edition. Robert E. Krieger Pub. Co., New York.

8. Hodges, C. F. 1978. Postemergent herbicides 
and the biology of Drechslera sorokiniana: 
Influence on severity of leaf spot on Poa 
pratensis. Phytopathology 68:1359-1363.

9. Hodges, C. F. 1980. Interaction of sequential 
leaf senescence of Poa pratensis and patho­
genesis by Drechslera sorokiniana as influenced 
by postemergent herbicides. Phytopathology 
70:628-630.

10. Hodges, C. F. 1984. Drechslera sorokiniana 
leaf spot development on sequentially senescent 
leaves of Poa pratensis exposed to postemer­
gence herbicide combinations. Plant Dis. 68:213- 
215.

11. Hodges, C. F. 1990. Endogenous ethylene 
response and chlorophyll loss in sequentially 
older leaves of Poa pratensis infected by 
Bipolaris sorokiniana. J. Plant Physiol. 136:670- 
674.

12. Hodges, C. E, and Blaine, W. M. 1978. 
Increase in Drechslera sorokinana leaf spot on 
maturing cultivars of Poa pratensis. Plant Dis. 
Rep. 62:127-129.

13. Hodges, C. F., and Campbell, D. A. 1993. 
Inhibition of ethylene biosynthesis and the 
endogenous ethylene and chlorophyll content of 
Poa pratensis leaves infected by Bipolaris 
sorokiniana. J. Plant Physiol. 142:699-703.

14. Hodges, C. F., and Campbell, D. A. 1994. 
Inhibition of endogenous ethylene biosynthesis 
by L-canaline in leaves of Poa pratensis infected 
by Bipolaris sorokiniana. Physiol. Mol. Plant 
Pathol, (in press).

15. Hodges, C. E, and Coleman, L. W. 1984. 
Ethylene-induced chlorosis in the pathogenesis 
of Bipolaris sorokiniana leaf spot of Poa 
pratensis. Plant Physiol. 75:462-465.

16. Klee, H. J., Hayford, M. A., Kretzmer, K. A., 
Barry, G. F., and Kishhore, G. M. 1991. Control 
of ethylene synthesis by expression of a bacterial 
enzyme in transgenic tomato plants. Pl. Cell 
3:1187-1193.

17. Murr, D. P., and Yang, S. F. 1975. Inhibition of 
in vivo conversion of methionine to ethylene by 
L-canaline and 2,4-dinitrophenol. Plant Physiol. 
55:79-82.

18. Nilsen, K. N., and Hodges, C. F. 1982. Hypo­
baric control of ethylene induced leaf senescence 
in intact plants of Phaseolus vulgaris L. Plant 
Physiol. 71:96-101.

19. Nilsen, K. N., Madsen, J. P., and Hodges, C. 
F. 1979. Enhanced Drechslera sorokiniana leaf 
spot expression on Poa pratensis in response to 
photoperiod and blue-biased light. Physiol. Plant 
Pathol. 14:57-69.

20. Nilsen, K. N., Hodges, C. F., and Madsen, 
J. P. 1979. Pathogenesis of Drechslera sorokini­
ana leaf spot on progressively older leaves of Poa 
pratensis as influenced by photoperiod and light 
quality. Physiol. Plant Pathol. 15:171-176.

21. Nilsen, K. N., and Hodges, C. F. 1980. Photo- 
morphogenically defined light and resistance of 
Poa pratensis L. to Drechslera sorokiniana. 
Plant Physiol. 65:569-573.

22. Pegg, G. F. 1976. The involvement of ethylene 
in plant pathogenesis. In: Heitefus, R. and P. H. 
Williams (eds.): Physiological Plant Pathology, 
Encyclopedia of Plant Physiology, New Series, 
Vol. 4, Springer-Verlag, New York, pp. 582-591.

23. Shurtleff, M. C., Fermanian, T. W, and 
Randell, R. 1987. Controlling Turfgrass Pests. 
Prentice-Hall, Inc., Englewood Cliffs, NJ.

24. Smith, J. D, Jackson, N., and Woolhouse, 
A. R. 1989. Fungal Diseases of Amenity Turf 
Grasses. E. & F. N. Spon, London.

25. Sommereyns, G., and Closset, J. -L. 1978. 
Preparation of helminthosporal by extraction 
with diethyl ether from culture filtrates of 
Helminthosporium sativum P.K. and B. Phyto­
path. Z. 92:202-210.

26. White, G. A., and Taniguchi, E. 1972. The 
mode of action of helminthosporal: II. Effect on 
the permeability of plant cell membranes. Can J. 
Bot. 50:1415-1420.

27. Yang, S. F., and Hoffman, N. E. 1984. 
Ethylene biosynthesis and its regulation in higher 
plants. Ann. Rev. Plant Physiol. 35:155-189.

HAND 
WATERING 
GREENS

There is a correct way.

by PAT GROSS

Hand watering greens may seem easy, but improper technique may actually cause 
more harm than good.

SUMMER IS HERE, and there is 

nothing an overheated mainte­
nance staff member would rather 
do than hand water greens on a hot 

afternoon. After all, it’s an easy job — 
grab a hose, hook it up to a quick 
coupler, and soak the grass. Right? 
Think again. That employee may be 
doing more harm than good if he or 
she is not familiar with the proper way 
to hand water greens.

A 1992 survey of the Green Section 
staff indicated that over-irrigation of 
greens was one of the top 10 mainte­
nance pitfalls. Over-watering contrib­
utes to disease development and 
inconsistent playing conditions. Even 
the best-designed irrigation system 
cannot produce a green with perfectly 
uniform moisture content throughout. 
Occasional hand watering is necessary, 
therefore, to compensate for localized 
dry spots or to cool the turfgrass 
canopy, and to maintain consistent 
playing conditions.

A couple of basic tools are necessary 
to do the job right — a soil probe and 
a hose-end nozzle that applies water 
in a gentle showering fashion. If regu­
lar soil probes cannot be purchased, 
effective probes can be made by cutting 
down a broken golf club shaft and 
cutting out a view port using a bench 
grinder. Staff members should be 
trained to check the greens with the 
soil probe to determine soil moisture 

levels before applying any water. Many 
disease and insect problems display 
symptoms similar to localized dry 
spots. Watering these areas will often 
make the situation worse. If the turf 
is wilting and adequate moisture is 
present, staff members should report 
this condition to the superintendent 
immediately.

Hand watering the wrong way can 
do as much damage to the playing 
surface as no watering at all. Puddles 
on the surface of the green can promote 
the development of pythium or a con­
dition known as “wet wilt.” If the 
soil is dry, water should be applied 
gradually, in a showering manner, so 
that puddling or runoff is avoided. The 
goal should be to match the water 
application rate with the infiltration 
rate of the soil. It may take several 
minutes and several light applications 
of water to wet the soil. For hydro- 
phobic areas, spiking the area first can 
improve water penetration. Spot appli­
cations of wetting agents also have 
been successful in treating localized 
dry spots; however, don’t overuse 
these products to compensate for ex­
cessive thatch accumulation, compac­
tion, or poor irrigation system cover­
age. In many cases, an aerifier will do 
a better job than a barrel of wetting 
agent.

Putting surfaces may wilt during 
the summer due to high temperatures, 

high winds, and hours of intense sun­
light. In these cases, syringing the 
greens with a light application of water 
can help revive the plant. The idea is 
to reduce the moisture stress of the 
leaf tissue and allow the plant to con­
tinue a balanced transpiration rate. 
Syringing is a very misunderstood 
operation. It is important to remember 
that you are only trying to sustain the 
grass plant with a very light application 
of water, not wet the soil.

Hand watering greens should not 
be forgotten on weekends. A super­
intendent’s worst nightmare is to return 
from a well-deserved weekend off only 
to find the greens scorched due to 
lack of water. (Actually, this is only 
one of several nightmares that super­
intendents have!) It is a good idea to 
schedule one or two people to come in 
on Saturday and Sunday afternoon to 
check the greens and hand water as 
necessary.

As a final note, check into the reason 
for the localized dry spots. These areas 
could be the result of poor sprinkler 
head coverage, worn nozzles, tree root 
encroachment, compaction, or exces­
sive thatch accumulation. Be sure to 
treat the cause and not just the 
symptoms.

PAT GROSS is an agronomist in the 
USGA Green Section’s Western Region.

JULY/AUGUST1996 

17

ON COURSE WITH NATURE

THIRSTY TURF

A short course in water conservation.

by RON DODSON

IT’S A beautiful spring morning. 

Water cascades across green fair­
ways and putting greens. To some, 
this is a beautiful sight indicative of 

the best efforts to ensure an enjoyable 
game of golf on the very best-kept turf. 
To other observers, it is the most visible 
evidence of environmental irresponsi­
bility — spraying water over roughly 
100 in-play acres on every golf course 
all across the country so that a few 
people can chase a little white ball. 
They consider it a waste of a critical 
natural resource that is needed for 
drinking, growing food, and providing 

one of the most basic elements of life on 
this planet.

Of all the environmental issues 
facing golf, water is very near the top 
of the list in most places around the 
country because it is a basic require­
ment of life. Every living thing — 
plants, humans, wildlife — needs its fair 
share in order to survive. Even though 
water often is considered a renewable 
resource, its use on golf courses is 
viewed by many as unnecessary and 
wasteful.

The fact of the matter is that many of 
us do waste water. How many times

have you seen sprinkler systems 
running while it’s raining? How about 
irrigation systems shooting water onto 
roadways, cart paths, or into water 
features? To people who are concerned 
about golf and its effect on the environ­
ment, these sights send cold chills 
down the spine. This apparent dis­
regard for the responsible use of water 
clearly does not project a positive 
image for golf, but nonetheless, I see 
these and other equally wasteful prac­
tices frequently. On the other hand, I 
have also seen many golf courses that 
use water very efficiently and also use

By using part-circle heads around lake banks, only turf areas are watered. 
Irrigating only in-play areas of the golf course and not water features 
or naturalized areas can greatly reduce water use at a course.

Establishing native vegetation in out-of-play areas conserves water and reduces pesticide use.

recycled water. These courses serve as 
buffers against other types of land use 
activities that might negatively impact 
the quality of water. So what can you 
do? How can a golf course demon­
strate its commitment to responsible 
water use and establish a more active 
role in water conservation efforts?

From a golf course perspective, using 
water effectively and efficiently can be 
approached from two angles: Plant 
Selection and Management and Build­
ing Infrastructure.

Plant Selection and Management

It should be obvious to anyone that 
the game of golf is played on living 
plants. From an environmental per­
spective it is extremely important that 
appropriate plants be chosen and then 
planted in the correct locations. To 
minimize water use, it’s important for 
golf course land managers to judiciously 
integrate low-water-use native vege­
tation — ground covers, grasses, and 
other plants — into the landscape. The 

challenge for the land manager is how 
to strike a balance between playing 
the game in a reasonable amount of 
time and not losing an unreasonable 
number of golf balls in tall grasses, 
roughs, and other non-play areas. The 
best approach is to target and carefully 
assess specific areas for naturalizing, 
and work slowly over a period of time 
to integrate native vegetation where it 
is most natural.

Also think about high-stress areas — 
steep slopes where golfers have a 
tendency to walk all of the time and 
wear out the turf, and areas where 
people tend to drive golf carts over and 
over again. These activities wear out the 
turf, calling for re-establishment and 
increased water use. Proper plant 
selection and traffic control play critical 
roles in managing these high-stress 
areas.

Selecting the appropriate type of 
turfgrass for the ecological region in 
which the course is located is also a 
critical decision. If you attempt to 

grow a warm-season grass in a cool­
season zone or grow any kind of 
turfgrass in an area that really wants 
to be a forest floor, you will have to 
create an artificial environment that 
will require all kinds of work, and 
yes, extra water. When in doubt, the 
USGA’s Turf Advisory Service is a 
great resource for help in selecting low- 
maintenance, disease-resistant turf­
grasses that ultimately will require less 
water to maintain.

Once you’ve started to naturalize 
the course and have selected the most 
appropriate turfgrasses for the eco­
logical region, it’s time to really focus 
on the irrigation system. It should be 
putting water where you need it, when 
you need it, and in the amount and 
rate that the targeted plants require. 
No more, no less. Check to make sure 
your irrigation system is really focusing 
on watering only those limited areas 
that really require watering. Remember, 
too, that irrigation is one of the most 
visible activities to the surrounding 

JULY/AUGUST1996 

19

community. Be careful not to reinforce 
their perception that golf courses waste 
extraordinary amounts of water.

Building Infrastructure

Water can also be efficiently utilized 
around and inside the buildings associ­
ated with the course. Around the 
buildings, use appropriate, native land­
scaping materials that not only benefit 
butterflies and hummingbirds, but re­
quire less water to maintain than some 
of the showy, heat-intolerant selections. 
Set an example for your members by 
installing low-flow toilets and water- 
restricter shower and sink heads in the 
clubhouse and the maintenance facility. 
Let your members know that you’ve 
made a commitment to the environ­
ment by using water responsibly.

Do yourself, the environment, and 
the game of golf a favor by doing your 
own simple water conservation audit. 
It’s not that hard and it doesn’t take 
that much time. Find out how much 
water you’re using and how much 
you’re paying for it now. Then, look 
around the course, do a tour of your 
buildings, and see if you can find ways 
of reducing water use without im­
pacting the business or the game. After 
a year goes by, check your water bills 
again and compare them. Many 
courses have done this and are 
amazed at the savings. Finally, don’t 
forget to publicize your good efforts — 
the financial savings, the maintenance 
savings, the human resource savings, 
and most important of all, the benefit 
to the environment!

In the Spotlight

Olde Florida Club: A Fully Certified 
Audubon Cooperative Sanctuary. A 

private course located in Naples, 
Florida, the Olde Florida Club has 
worked hard to conserve water both on 
and off the course. A state-of-the-art 
irrigation system is just the beginning. 
As Darren Davis, superintendent of the 
Olde Florida Club, states, the irrigation 
system is “only pieces of hardware 
that can be seen from the surface. Also 
important are the design, proper place­
ment, and maintenance of components 
under the surface.” Focusing on proper 
pipe sizes and irrigation heads is critical 
to an efficient irrigation system. The 
irrigation pipes at the Olde Florida 
Club are laid in a loop system that 
allows all areas of the course to be 
watered from two directions, furthering 
irrigation efficiency and turf health.

At Olde Florida, the irrigation system 
is hooked into a weather station that 
provides temperature, humidity, wind 
speed and direction, and solar radia­
tion, which are used to calculate 
evapotranspiration (ET) rates. Golf 
Link, a satellite/computer Doppler 
Weather Radar System, is also used to 
determine when storms will be in the 
area, with an accuracy of plus or minus 
15 minutes. Watering at less than 100% 
of the ET rate further maintains turf 
health and reduces water used at the 
course.

Other measures that have been used 
to help reduce water use include con­
verting some areas of bermudagrass 
to the more drought-tolerant cordgrass, 
using compressed air at the wash pit 
to lessen water used during the clean­
ing of equipment, installing water-sav­
ing toilets, not irrigating native areas 
or water features, and using mulch and 
native plants for landscaping.

Allowing natural vegetation, including tall grasses, shrubs, and trees to 
flourish in out-of-play areas along the number four fairway of Egypt Valley’s 
Ridge Course reduces the amount of turf that needs to be irrigated.

Egypt Valley Country Club: A Fully 
Certified Audubon Cooperative Sanc­
tuary. Located in Ada, Michigan, Egypt 
Valley Country Club has done an 
incredible job of conserving water, with 
a yearly reduction of about nine million 
gallons. By keeping careful watch over 
course watering needs using weather 
data, a soil probe, and turf color, the 
different areas of the course are only 
watered on an as-needed basis. Water 
is further conserved by the use of 
drought-tolerant turf species and water­
ing at less than 100% the ET rate. 
Jeffrey Holmes, Egypt Valley’s superin­
tendent, and Craig Hoffman, the assis­
tant superintendent, have also reduced 
irrigated turf by naturalizing areas, 
using mulch produced on-site around 
landscaping, hand watering during 
high-evaporation periods, and irrigat­
ing at night when evaporation is at its 
lowest.

Village Links of Glen Ellyn: A Fully 
Certified Audubon Cooperative Sanc­
tuary. This public course provides a 
wonderful example of an integrated 
water conservation plan. Located in 
Glen Ellyn, Illinois, this 235-acre 
course has successfully demonstrated a 
32% reduction in water use. One fac­
tor in this reduction is the extensive 
naturalizing that has been done at the 
course. Fairway coverage was reduced 
from 62 to 42 acres, and more than 40 
acres of the course were restored to 
native grassland and prairie habitat. 
Timothy Kelly, Village Links of Glen 
Ellyn’s superintendent, and Chris 
Pekarek, assistant superintendent, have 
been maintaining water usage and rain­
fall records since 1977. The golf course 
itself is a designated flood detention 
area, and storm water runoff collected 
in course ponds is often used for irri­
gation. A system of valves allows trans­
fer of water between ponds. Recently 
they adjusted the lake overflow struc­
ture to reduce well use and increase the 
use of recaptured and recycled water. In 
addition, testing sprinklers and repair­
ing them in a timely manner, priori­
tizing water areas and hand watering 
during drought, and mulching and 
using drip irrigation in landscaped 
areas have all contributed to the Village 
Links of Glen Ellyn’s successful water 
conservation program.

RON DODSON is president of Audubon 
International, based in Selkirk, N.Y. He 
directs environmental activities for golf 
courses, schools, corporate properties, 
and homeowners’ backyards.

NEWS NOTES

LABORATORY ACCREDITATION 
PROGRAM ANNOUNCED FOR 
PUTTING GREEN MATERIALS 
TESTING

In cooperation with the USGA, the 
American Association for Laboratory 
Accreditation (A2LA) has formulated a 
program for accrediting laboratories 
that test putting green materials. This 
initiative will provide a service to golf 
by maintaining a list of dependable 
laboratories available for analyzing 
components specified in the USGA 
Recommendations for Putting Green 
Construction.

A2LA, headquartered in Gaithers­
burg, Maryland, is a nonprofit, non­
governmental, public service, member­
ship organization organized primarily 
for the purpose of formally recognizing 
the competence of testing laboratories 
that meet stringent international cri­
teria and have been found competent 
to perform specific tests or types of 
tests. It has accredited over 800 labora­
tories in fields as varied as biology, 
chemistry, construction materials, geo­
technical, environmental, mechanical, 
and thermal testing.

“We are pleased to work with the 
United States Golf Association in the 
development of a program specifically 
to support the competence of testing in 
the putting green materials industry,” 
Roxanne Robinson, vice president of 
A2LA, said.

One of the major objectives of this 
program is to provide golf course super­
intendents, officials, architects, build­
ers, and suppliers who need putting 
green testing services with a list of 
physical soil testing laboratories whose 
competence is regularly evaluated and 
documented.

The accreditation process applicable 
to the special putting green laboratory 
accreditation program was designed to 
meet the requirements of the USGA 
and of golf courses that build greens to 
USGA recommendations. It requires 
meeting general and specific criteria. In 
order to be accredited in this program, 
a testing laboratory must be competent 
to perform, at a minimum, the follow­
ing tests:

1. Dry Preparation of Soil Samples 
for Particle-Size Analysis and Deter­
mination of Soil Constants;

2. Particle-Size Analysis of Soil;

3. Standard Test 
Method for Mois­
ture, Ash, and 
Organic Matter of 
Peat and Other 
Organic Soils;

4. Standard Test 
Method for Satu­
rated Hydraulic 
Conductivity, Water 
Retention, Porosity, 
Particle Density 
and Bulk Density 
of Putting Green 
and Sports Turf 
Root Zones;

5. Standard Test 
Method for Particle- 
Size Analysis and 
Sand Shape Grad­
ing of Golf Course 
Putting Green and 
Sports Field Root 
Zone Mixes;

6. Standard Test 
Method for Organic 
Matter Content of 
Putting Green and 
Sports Turf Root 
Zone Mixes.

Additional turf 
tests can be added 
to a laboratory’s 
scope as desired.

A2LA-accredited laboratories have met rigorous competency 
standards for testing materials used in the construction of 
USGA greens.

Laboratories seek­
ing accreditation 
must allocate ap-
proximately $4,000 every two years, 
which includes a three-day, on-site 
inspection and review. This on-site 
review is conducted by one of several 
A2LA assessors chosen on the basis of 
their testing or calibration expertise. 
Currently, the members of this assess­
ment team include three retired pro­
fessors: Dr. Don Waddington from 
Pennsylvania State University, Dr. Bill 
Dest from the University of Connecti­
cut, and Dr. Coleman Ward from 
Auburn University. Each laboratory’s 
accreditation lasts for two years, at 
which time they must undergo reexami­
nation.

Another requirement of accreditation 
is participation in the Western States 
Proficiency Testing Program conducted 
by Dr. Robert O. Miller of the Univer­
sity of California at Davis and Dr. 
Janice Kotuby-Amacher of Utah State

University. It will involve a quarterly 
exchange of golf-green soil materials 
on which each laboratory performs 
physical analysis. Each laboratory will 
receive a quarterly report reviewing its 
work, plus notification of all values 
exceeding the program warning limits. 
Annually, each laboratory and the 
USGA will receive a report of the entire 
program with individual performance 
scores.

The Green Section Record regularly 
will publish a list of laboratories 
accredited by A2LA. This list will also 
appear on the USGA’s Internet site. 
Only laboratories that have passed this 
rigorous testing process will appear, 
and the USGA recommends that only 
A2LA-accredited laboratories be used 
to test materials for building greens 
according to USGA recommendations. 
At this time, two laboratories have 

JULY/AUGUST1996 

21

in Selkirk, N.Y. It will be used to help 
computerize Audubon International’s 
substantial database of statistical infor­
mation about golf courses that it has 
gathered through its involvement over 
the past six years in managing the 
Audubon Cooperative Sanctuary Pro­
gram for Golf Courses.

Complete information about each of 
these grants may be obtained by con­
tacting either Dr. Peter Stangel, NFWF, 
1120 Connecticut Avenue N.W, Suite 
900, Washington, DC, (202) 857-5676; 
or Dr. Kimberly Erusha or Marty 
Parkes of the USGA Green Section, 
P.O. Box 708, Far Hills, NJ 07931, (908) 
234-2300.

PINE NEEDLES NOW 
A SAFE HARBOR

“This program is not about regula­
tions. It’s about partnerships. It’s not 
about mandates. It’s about incentives; 
architects, developers, golfers, and 
wildlife experts working together.”

With these words, U.S. Secretary of 
the Interior Bruce Babbitt summarized 
an agreement, known as the Safe 

Harbor Program, signed by the U.S. 
Fish & Wildlife Service and the Pine 
Needles Lodge & Golf Club during the 
recent U.S. Women’s Open held at the 
facility. This initiative, officially known 
as the Sandhills Conservation Plan, 
guarantees that private landowners 
such as golf courses will not be subject 
to restrictions under the Endangered 
Species Act after they succeed in 
attracting threatened species to their 
land and later decide to convert the 
property to alternative uses.

The federally endangered species in 
question in the Sandhills of North 
Carolina, where Pine Needles is located, 
is a bird called the Red-Cockaded 
Woodpecker (RCW). This seven-inch- 
long bird excavates nesting cavities in 
live pine trees usually more than a 
century old. RCWs thrive in a golf- 
course environment because they pre­
fer the open pines often found on golf 
courses throughout the area compared 
to dense forests with significant under­
brush. More than a dozen of the 
approximately 40 golf courses in the 
Pinehurst area have enrolled to date, 
with the Pinehurst Resort leading the 
way by enrolling last year (Green 
Section Record, July/August 1995). In

U.S. Secretary of the Interior Bruce Babbitt (far right) confers with 
Mark Cantrell of the U.S. Fish and Wildlife Service about the Safe 
Harbor Program operating in the Pinehurst region.

passed muster with A2LA. These 
facilities are:

Brookside Laboratories, Inc.
308 S. Main Street
New Knoxville, OH 45871
Attn: Mark A. Flock
(419) 753-2448
FAX (419) 753-2949
Thomas Turf Services, Inc.
1501 FM 2818, Suite 302
College Station, TX 77840-5247
Attn: Bob Yzaguirre/Jim Thomas 
(409) 764-2050
FAX (409) 764-2152

Questions about the accreditation 
process should be directed to The 
American Association for Laboratory 
Accreditation, 656 Quince Orchard 
Road, Gaithersburg, MD 20878; (301) 
670-1377 or FAX (301) 869-1495. Attn: 
Roxanne Robinson or Ron Bell.

WILDLIFE LINKS
GRANTS ANNOUNCED

The United States Golf Association 
(USGA) has awarded three grants 
totaling approximately $100,000 to 
initiate Wildlife Links, golf’s first 
comprehensive program to investigate 
its relationship with wildlife and its 
habitat. The program is coordinated by 
the National Fish and Wildlife Foun­
dation (NFWF), based in Washington, 
D.C.

The Colorado Bird Observatory, 
headquartered in Brighton, Colo., re­
ceived the first grant. It will be used to 
create a manual that will provide golf 
course architects and superintendents 
with practical information about how 
to enhance golf course habitat for bird 
species. The working title of the pub­
lication is Golf Courses and Bird 
Conservation: A Management Manual, 
and it will appear next spring.

Donald F. Harker and Gary W. Libby, 
environmental researchers located in 
Frankfort, Ky, were awarded a grant to 
underwrite production of a publication 
with the tentative title Wetlands 
Management Manual for Golf 
Courses that is expected to appear 
in early 1997. This illustrated booklet 
will contain narrative, drawings, case 
studies, and key restoration techniques 
to help golf course superintendents 
understand wetlands and create pro­
grams to create, conserve, and manage 
them.

The final grant has been given to 
Audubon International, headquartered 

22  USGA GREEN SECTION RECORD

vidual course site is a decision that 
must be made by local communities. 
The principles are voluntary and are 
not intended for use in making judg­
ments about socio-economic issues. 
They assume that regulatory compli­
ance jias been achieved and are 
designed to provide opportunities for 
those involved in the golf industry to go 
beyond minimum standards required 
by law.

The document appears in its entirety 
on the USGA’s Internet site on the 
World Wide Web at http://www.usga.- 
org. Copies may also be obtained 
through the USGA Green Section at 
(908) 234-2300.

USGA RESEARCH SUMMARIES 
AVAILABLE

The 1995 Turfgrass and Environ­
mental Research Summary is now 
available from the USGA.

The Turfgrass and Environmental 
Research Program, sponsored by the 
USGA, has three primary goals: de­
velop turfgrasses for golf courses that 
substantially reduce water use, pesti­
cide applications, and maintenance 
costs; develop management practices 
for new and established turfs that pro­
tect the environment while providing 
quality playing surfaces for the game 
of golf; and encourage young scientists 
to become leaders in turfgrass research. 
The accomplishments of the 41 current 
research projects funded through the 
USGA Turfgrass and Environmental 
Research Program are summarized in 
the 1995 research summary.

Also included in the document is a 
list of the ten research projects to be 
conducted on the construction and 
maintenance of greens. The goal of 
this research is to identify the best 
combinations of construction, grow-in 
procedures, and post-construction 
maintenance practices that prevent 
long-term problems, reduce environ­
mental impacts, and produce high- 
quality playing surfaces. Beginning in 
1996, this is a five-year research effort.
The 84-page research summary is 
available free of charge by leaving your 
postal mailing address on the USGA 
Internet site (http://www.usga.org), 
contacting Mary Jane Kymer at the 
USGA Green Section (908-234-2300), 
or by writing to the USGA Green 
Section, P.O. Box 708, Far Hills, NJ 
07931. In the near future, the entire 
research summary will be available on 
the USGA Internet site.

JULY/AUGUST1996 

23

Secretary Babbitt with USGA President Judy Bell during the signing ceremony at the 
1996 U.S. Women’s Open.

excess of 20,000 acres of privately 
owned land, much of it golf-course 
acreage, now fall under the Safe Harbor 
Program.

“What I’d like to do is talk about two 
of my favorite subjects, woodpeckers 
and golfers, and the very happy con­
junction of the two and the partnership 
that is now emerging between the 
owners and managers of golf courses 
and the surrounding natural values of 
the land,” Babbitt said during the sign­
ing ceremony.

“Golf courses, at their best, are very 
closely designed and related to the 
natural environment and the land­
scape. And indeed the extraordinary 
draw of the golf course is a function 
both of its challenge to the player and 
the way that it reveals and relates to 
the landscape,” Babbitt continued. 
“And what we have found here in the 
Sandhills of North Carolina means that 
good golf courses are also excellent 
woodpecker habitat. It ought to be 
possible to design and operate golf 
courses in a way that actually enhances 
wildlife values. That’s an important 
lesson that I think every person who’s 
interested in the game of golf can take 
all over this United States of America 
is that the presence of golf courses 
can actually increase the amount of 
wildlife.”

ENVIRONMENTAL PRINCIPLES 
ADOPTED

Consider this scenario: Delegates 
from various entities throughout the 
nation meet periodically in extended 
discussions, attempting to forge a com­
promise among seemingly disparate 
interests and goals. These gatherings 
extend over 12 months and involve 
countless written revisions. Finally, a 
document is endorsed that articulates 
the much-thought-out principles.

The reference in this case is not the 
Continental Congress and its activities 
leading to ratification of the Declaration 
of Independence. Instead, it represents 
more recent activities of a myriad of golf 
and environmental interests, and an 
innovative document called Environ­
mental Principles for Golf Courses 
in the United States. Unveiled during 
the second Golf and The Environ­
ment Conference, held in Pinehurst, 
N.C., in mid-March, it offers a frame­
work under which environmental 
excellence is stressed in all aspects of 
golf course planning and siting, design, 
construction, maintenance, and facility 
operations.

The principles are envisioned as a 
tool for national use while keeping in 
mind that any assessment of the en­
vironmental compatibility of an indi­

ALL THINGS CONSIDERED

SENSIBLE CHOICES

Making better choices of new bentgrass varieties.

by PAUL VERMEULEN

UNTIL THE EARLY 1990s, 

“Penncross” was the leading 
choice for seeding new greens in 
all but the bermudagrass regions. The 

choice was an easy one in those days, 
because there were no other varieties of 
equal quality. Today, there are 28 bent­
grass varieties under review in the 
National Turfgrass Evaluation Program 
(NTEP), and the list grows longer each 
year.

How can someone evaluate his own 
circumstances and make a sensible 
choice when there are so many new 
varieties to choose from? Complicating 
matters further is the burgeoning desire 
to improve long-term stand perfor­
mance by blending two or more 
varieties. This practice is based on the 
survival-of-the-fittest premise and is 
well established in the Kentucky 
bluegrass and perennial ryegrass 
markets.

Some people rely on testimonials 
from fellow turf managers or informa­
tion published in popular trade 
journals to make varietal choices. 
Others remain loyal to their favorite 
breeder and plant only varieties de­
veloped by that individual. Although 
these selection methods can be used 
successfully in some cases, their 
reliance on subjective information is a 
cause for concern.

Let’s evaluate the reliability of 
testimonials from fellow turf managers. 
This approach to selecting a variety 
simply tells you that someone else is 
satisfied with the choice they have 
made. But because a fellow turf 
manager is satisfied with a particular 
variety does not mean it is the best 
choice for your course.

Likewise, shopping for a creeping 
bentgrass variety from a single breeder 
can have serious drawbacks. The per­
formance of a variety at a breeder’s 
home base may or may not have a 
bearing on how well it will perform 
in another location under different 
climatic conditions or management 
practices. If a breeder uses germplasm 
without genetic tolerance to a specific 
pathogen or environmental extreme 
that is common in your region, their 
varieties may not perform as well as 
others that are available.

When selecting two or more varieties 
for a blend, it is important to consider 
several factors. Simply choosing some­
thing old, something new, something 
heat tolerant and something disease 
resistant based only on the survival-of- 
the-fittest premise is somewhat ludi­
crous. The best candidates forblending 
are those with similar NTEP rankings 
for overall quality, color, texture, spring 
greenup, and spring, summer, and fall 

One information source to ease the daunting task of selecting a 
variety for a new putting green can be found at on-site evaluation 
plots maintained with standard maintenance practices.

density. If the components of a blend 
are not physically similar, their separa­
tion over time will erode the visual 
quality of a putting green. If compatible, 
blends should also include varieties 
that have disease resistance or stress 
tolerances that are pertinent to the 
course’s location and environmental 
circumstances.

The most sensible method of choos­
ing between varieties or blends is one 
that few courses employ because of 
either cost or inconvenience. Given 
the luxury of time, the performance 
characteristics for each variety/blend 
should be reviewed in on-site evalua­
tion plots maintained using standard 
maintenance practices. An ideal 
location for the plots, albeit a possible 
inconvenience to a few players, is on 
the practice putting green. In this loca­
tion the plots can be cared for using 
maintenance practices similar to those 
employed on the course, and the plots 
can be subjected to the wear and tear 
of pedestrian traffic. Also, to ensure 
that the evaluation is not tainted by 
the effects of traffic patterns, partial 
shading, inconsistent soil type, etc., the 
plots should be replicated and spaced 
randomly throughout the putting sur­
face. The USGA, GCSAA, and NTEP 
will be establishing bentgrass trials on 
golf course practice greens at 15 loca­
tions throughout the country in 1997.

Choosing the best variety or blend 
for greens located in all comers of the 
globe requires sorting through the 
growing list of choices using sensible 
selection criteria and methods. If your 
course has time to plan ahead, there is 
no excuse for not evaluating potential 
varieties/blends using the establish­
ment of evaluation plots located on 
the practice green or nursery.

PAUL VERMEULEN is an agronomist in 
the USGA Green Section’s Mid-Continent 
Region. The opinions expressed are those 
of the author and do not necessarily 
reflect those of the USGA Green Section.

USGA PRESIDENT 
Judy Bell

GREEN SECTION 
COMMITTEE CHAIRMAN
Thomas W Chisholm 
26101 Northwestern Highway 
Southfield, MI 48076

EXECUTIVE DIRECTOR
David B. Fay

EDITOR
James T. Snow

ASSOCIATE EDITOR
Kimberly S. Erusha, Ph.D.

STAFF WRITER
Marty Parkes

©1996 by United States Golf Association®

Subscriptions $15 a year, Canada/Mexico 
$18 a year, and international $30 a year 
(air mail).

Subscriptions, articles, photographs, and corre­
spondence relevant to published material should 
be addressed to: United States Golf Association 
Green Section, Golf House, P.O. Box 708, Far 
Hills, NJ 07931.

Permission to reproduce articles or material in 
the USGA GREEN SECTION RECORD is 
granted to newspapers, periodicals, and educa­
tional institutions (unless specifically noted 
otherwise). Credit must be given to the author, 
the article’s title, USGA GREEN SECTION 
RECORD, and the issue’s date. Copyright 
protection must be afforded. To reprint material 
in other media, written permission must be 
obtained from the USGA. In any case, neither 
articles nor other material may be copied or used 
for any advertising, promotion, or commercial 
purposes.

GREEN SECTION RECORD (ISSN 0041-5502) 
is published six times a year in January, March, 
May, July, September, and November by the 
UNITED STATES GOLF ASSOCIATION®, Golf 
House, Far Hills, NJ 07931. Postmaster: Send 
address changes to the USGA Green Section 
Record, P.O. Box 708, Golf House, Far Hills, NJ 
07931-0708.

Periodicals postage paid at Far Hills, NJ, and 
other locations. Office of Publication, Golf 
House, Far Hills, NJ 07931.

Visit the USGA’s Internet site on the 
World Wide Web. The address is: 
http://www.usga.org

Turfgrass Information File (TGIF): 
(800) 446-8443

NATIONAL OFFICE:
United States Golf Association, Golf House
P.O. Box 708, Far Hills, NJ 07931 • (908) 234-2300 • Fax (908) 234-1513
James T. Snow, National Director
Kimberly S. Erusha, Ph.D., Director of Education 
Marty Parkes, Manager, Green Section Communications

GREEN SECTION OFFICES:

Research:
P.O. Box 2227, Stillwater, OK 74076 • (405) 743-3900 • Fax (405) 743-3910
Michael P. Kenna, Ph.D, Director

Northeastern Region:
P.O. Box 4717, Easton, PA 18043 • (610) 515-1660 • Fax (610) 515-1663
David A. Oatis, Director • Matthew C. Nelson, Agronomist

500 N. Main Street, Palmer, MA 01069 • (413) 283-2237 • Fax (413) 283-7741 
James E. Skorulski, Agronomist

Mid-Atlantic Region:
P.O. Box 2105, West Chester, PA 19380-0086 • (610) 696-4747 • Fax (610) 696-4810
Stanley J. Zontek, Director • Keith A. Happ, Agronomist

Southeastern Region:
P.O. Box 95, Griffin, GA 30224-0095 • (770) 229-8125 • Fax (770) 229-5974
Patrick M. O’Brien, Director
4770 Sandpiper Lane, Birmingham, AL 35244 • (205) 444-5079 • Fax (205) 444-9561
Christopher E. Hartwiger, Agronomist

Florida Region:
P.O. Box 1087, Hobe Sound, FL 33475-1087 • (407) 546-2620 • Fax (407) 546-4653
John H. Foy, Director

Mid-Continent Region:
720 Wooded Crest, Waco, IX 76712 • (817) 776-0765 • Fax (817) 776-0227 
James F. Moore, Director

P.O. Box 1130, Mahomet, IL 61853 • (217) 586-2490 • Fax (217) 586-2169
Paul H. Vermeulen, Agronomist

North-Central Region:
P.O. Box 15249, Covington, KY 41015-0249 • (606) 356-3272 • Fax (606) 356-1847
Robert A. Brame, Director

P.O. Box 5069, Elm Grove, WI 53122 • (414) 797-8743 • Fax (414) 797-8838
Robert C. Vavrek, Jr., Agronomist

Western Region:
5610 Old Stump Drive N.W, Gig Harbor, WA 98332
(206) 858-2266 • Fax (206) 857-6698
Larry W. Gilhuly, Director

22792 Centre Drive, Suite 290, Lake Forest, CA 92630
(714) 457-9464 • Fax (714) 457-9364
Patrick J. Gross, Agronomist • Michael T. Huck, Agronomist

iTOW rwranws

KNOWLEDGE OF THE RULES

Question: During a recent round of golf, I observed a fellow-competitor pressing down a spike 
mark. Knowing that there is a Rule against this practice, I informed him of his misdeed. He said 
that he was pressing down an old hole plug, and because the spike mark was in the old hole plug 
that he was within the Rules. Who is correct? (Wyoming)

Answer: Pay up; your fellow-competitor was correct. Rule 16-la permits touching the 
line of putt in repairing an old hole plug. If the spike mark had not been within the 
hole plug, the ruling would have been different. We offer another alternative. Encourage 
all players at your golf course to use the spikeless alternatives that have become 
increasingly popular during the past several years. The issue of spike marks will be 
eliminated, along with a few more strokes off your score due to the smoother putting 
surface.

FOR STATE-OF-THE-ART IRRIGATION

Question: The golf course I play at just purchased and installed a new state-of-the-art irrigation 
system. I don’t understand why we continue to see employees pulling hoses and hand watering 
spots on greens, tees, and fairways. Can you help me understand why it is necessary to hand water 
when we have a well-designed and functioning irrigation system? (Kentucky)

Answer: A well-designed and functioning irrigation system is a tremendous asset and 
tool that many courses do not have. Nevertheless, the cardinal rule in golf turf 
management is to maintain the grass as dry as possible. This rule means programming 
the irrigation system conservatively, which may result in occasionally missing areas or 
running certain areas on the dry side. Hand watering is necessary to supplement 
irrigation on problem areas or spots that simply require a bit more irrigation. The labor 
investment to hand water occasionally is money well spent. Even the best of irrigation 
systems do not eliminate the need for occasional hand watering in the pursuit of good 
quality playing surfaces and healthy turf.

IMPROVES TURF QUALITY

Question: Our greens seem to become hard and unreceptive to golf shots, especially during the 
summer months when the golf course dries out. We encourage our superintendent to water more 
frequently to soften the surfaces, but he refuses, saying that heavy watering will only make the 
greens harder and hurt turf quality. Help! A Concerned Golfer. (Massachusetts)

Answer: The irrigation system should not be used to keep the greens soft, as this method 
will result in excessive water applications that can lead to further soil compaction, a 
reduction in surface quality, and conditions that favor weaker grass plants. A long-range 
program of aerification and topdressing with a good quality topdressing material is the 
best approach for creating a surface that will accept a properly hit golf shot. Dry, firm 
surfaces generally are the most desirable for maintaining high quality turf and good 
playing conditions.