Does Fertilizer/Pesticide Use on a Golf Course Put Water Resources in Peril?
What has happened? Why are golf courses now considered by some to
be analogous to toxic waste dumps? Of course, the answer to these
questions is complex, and probably has more to do with
sociological and psychological issues than it does with answers
that can be provided by turfgrass scientists and their research.
However, significant research is being conducted to address these
concerns. Before discussing this research, it would be prudent to
discuss some of the other aspects of why golf courses have
created such environmental concern.
Ever since the book Silent Spring was published, a pesticide
consciousness has prevailed in this country that has led to
important and necessary legislation and regulation of pesticide
development, sale, and use. However, as the Environmental
Protection Agency has stiffened requirements for registration of
new compounds, required additional information for
re-registration, and identified various contaminated dump sites,
the various forms of news media have consistently provided the
public with a one-dimensional view of pesticides. From Times
Beach to the apple and alar scare, our mass media have tended to
sensationalize any story pertaining to pesticides. The death of a
navy man who had played golf at Army-Navy Country Club was
attributed to pesticide exposure (Daconil). Where was the press
when the case was tried in court, and Daconil exposure was ruled
out as a cause of death (even to the satisfaction of the widow)?
Such positive information about pesticides is rarely seen by the
public, if it ever is. Unfortunately, the public depends heavily
on the news media for its daily dose of education. Therefore,
opinions about issues are shaped by the articles the public reads
or the news stories it sees and hears. As long as doom and gloom
are perceived to be what the public wants to know, the one-sided
presentation of information pertaining to pesticides will
The public's perception of pesticide use is shallow and for
the most part uneducated. Most people believe that when a
pesticide is applied to anything, it either leaves the site in
runoff or seeps into the ground and contaminates groundwater.
They have no comprehension of ultra-violet light degradation,
volatility, soil and organic matter attenuation, and microbial
degradation. The fate of a pesticide applied to any site is an
extremely complex arrangement of possibilities that cannot be
explained in the simple terms that serve as popular perceptions.
Consequently, for the past two decades, almost any use of
pesticides has been perceived to cause a negative impact on all
aspects of the environment. By association, golf courses, the
former providers of green space and natural setting, have been
found to be on the hit list of environmental groups.
Twenty years ago, Golfdom magazine (Vol. 43, No. 4) published an
article entitled "Golf Resort of the Future." The
article quoted a National Golf Foundation report that indicated
40 percent of the new golf clubs under construction were part of
large real estate developments. This sounds familiar even today,
with the country going through a golf course construction boom.
The article discussed our mobile society and the need for planned
communities. It mentioned lush, rolling, clean, green
recreational areas, surrounded by houses and apartment buildings.
Emphasis was always placed on the open spaces and the importance
of natural settings within any development. Permitting such
projects and the likelihood of their approval by planning
commissions, zoning hearing boards, and other agencies was
enhanced by the inclusion of a golf course. Things have certainly
changed. A golf course in a development plan today precipitates
concerns about fertilizer and pesticide use, and their impact on
runoff and groundwater.
The golf course community has always been concerned about water
quantity and quality. In 1968 James Moncrief, Director of the
Green Section's Southern Region, wrote about water in the
November issue of the GREEN SECTION RECORD. In addition to
hydrology and the principles of applying water to land, he
discussed groundwater and chemicals in the water. His primary
message dealt with being certain of the quantity and quality of
available water before irrigation systems were installed.
He was concerned with the health of the turf should it be
irrigated with water of inferior quality. The concern today is
for whether or not what is applied to the turf unnecessarily
degrades the quality of the water emanating from the golf course.
Ironically, in the same GREEN SECTION RECORD issue (in fact, the
next article), Dr. A. Robert Mazur, then an agronomist with the
USGA and now a turfgrass specialist at Clemson University,
published an article entitled "The Fate of Herbicides."
The basic thrust of the story dealt with those pesticide issues
discussed previously in this article.
Even earlier, in the July, 1964, issue of THE RECORD, Dr. Marvin
Ferguson, then Mid-Continent Director of the Green Section, wrote
"Pesticides -Boon or Bane?" He credited the use of
pesticides for the great deal of progress that had been made in
improving the quality of golf courses. He also mentioned the
fears of some for the use of pesticides. He concluded that all
those involved in the use or commerce of pesticides have an
obligation to be aware of the potential dangers inherent in the
materials they use. He made the point that all pesticides should
be used according to the instructions of the manufacturer, stored
safely, and handled with a knowledge of possible effects upon
plants, animals, and man. Ferguson's article is just as
appropriate and pertinent today.
Most of today's superintendents are well trained and educated
in pest management and pesticide use. Even so, it is popularly
assumed that pesticides are overused on golf courses because of
the "intensive management" required to provide
high-quality playing conditions for an increasingly demanding
Pest management on golf courses is usually a fairly visible
practice, and at times requires sequential applications of
chemicals at specific intervals, depending on the pest.
Fertilizer use is also assumed to be relatively high to maintain
aesthetic quality and a growth rate that can accommodate wear. It
is not surprising, therefore, that some assume turf management
has a high potential to contaminate water supplies. It is obvious
that research is needed on the effects nutrients and pesticides
might have on runoff and leachate.
The facilities for this project are located at the Landscape
Management Research Center near the main campus of The
Pennsylvania State University. The site, located on a variable
slope (9 to 14 percent), was formerly used for soil erosion
research, and was allowed to return to a natural state for nearly
40 years before being renovated to accommodate this project. The
soil is a Hagerstown series, originating from limestone residuum,
and typical of the karst geology found in the Ridge and Valley
province of central Pennsylvania. The surface soil was texturally
classified as clay (23 percent sand, 36 percent silt, 41 percent
clay), based on particle size analysis at the time of tillage.
Renovation of the site took place from 1982 to 1985 and included
grading, installation of individual plot irrigation systems,
installation of lysimeters in the upper and lower portions of the
plot slopes, restoration of collection weirs, fabrication of flow
monitor and subsampling equipment, and linkage of automated
datalogging and computer systems.
Surface preparation for turfgrass establishment consisted of
rototilling (102mm depth), stone removal, rolling, and leveling
by hand raking.
Plots were 6.45m by 18.9m and were separated by plastic edging
material that extended 102mm into the soil. Edging was laid to
eliminate inter-plot surface and near-surface movement of water
or applied chemicals. Each plot contained 21 pop-up sprinkler
irrigation heads calibrated to deliver water at a uniform rate of
76mm/ hr during 1985. In 1986, the system was fitted with nozzles
calibrated to deliver 152mm/ hr.
An opoxy-coated concrete weir was positioned at the bottom of
each slope to intercept runoff water. The runoff was directed
through a galvanized steel chute into a building that housed the
flow-monitoring and subsampling apparatus. Pan lysimeter-type
subsurface sampling devices were installed 152mm below the soil
surface to capture percolating water. The depth capacity of the
samplers was 38mm.
The lysimeters were constructed from round, high-density
polyethylene containers filled with 16mm diameter glass marbles
as ballast. A piece of polyester geotextile material separating
the glass ballast from the overlying soil prevented sediment from
entering the lysimeters. Polyethylene fittings at the top and
bottom of the containers facilitated venting and emptying the
samplers. Water samples were withdrawn through a centrifugal
Inside the building, water from the chute flowed through a
polyethylene splitting chamber (for subsample collection) and
into a partitioned galvanized steel tank. A length of eight-inch
corrugated PVC pipe was suspended below the splitter to act as a
baffle to minimize wave formation in the tank. Water accumulating
in the receiving side of the tank flowed through a standard
hydrologic V-notch into the exit chamber and was pumped to a
storage/ disposal tank. A float and counterweight assembly was
positioned in the receiving side of the partitioned tank and was
banded to a pulley attached to a potentiometer. As the float
assembly responded to changing water levels in the tank (a
function of runoff flow rate), it turned the potentiometer and
produced a voltage signal associated with that water level and
The voltage signal in each building was read every 60 seconds by
a microprocessor-equipped datalogger in an adjacent lab. The
voltage signals were converted into flow rates, and the data were
recorded on a bulk storage tape drive, accessible by PC
communication software. The data collection system could be
activated manually, or automatically by the detection of rainfall
at an adjacent weather station.
Runoff water for quality analyses was subsampled continuously
from the splitting chamber over the course of any runoff event.
Water was transferred at a rate of 16ml/min to a liter
high-density polyethylene bottle.
Three turfgrass types were established in late June of 1985. The
three experimental treatments (establishment method) were: 1) a
seed mixture consisting of 25 percent Merit Kentucky bluegrass,
25 percent Julia Kentucky bluegrass, 20 percent Shadow chewings
fescue, and 30 percent Citation perennial ryegrass; 2) a
contractor's seed mixture containing 60 percent annual
ryegrass, 20 percent common Kentucky bluegrass, and 20 percent
creeping red fescue; and 3) a three-year-old Pennsylvania
Certified 100 percent Kentucky bluegrass sod grown from the
following seed mixture: Adelphi (25 percent), Baron (25 percent),
Fylking (25 percent), and Nassau (25 percent). All treatments
received a complete fertilizer (according to soil test
recommendation) at planting. Soil pH was 7.0 and no lime was
Plots were mowed weekly to a height of approximately two inches
(clippings removed) during the growing season. Irrigation was not
employed as a routine maintenance practice, however scheduled
irrigations were used to produce runoff and leachate samples.
Mechanical cultivation techniques such as core aeration, slicing,
or spiking were not used.
Pesticides included in the study were pendimethalin, 2,4-D,
2,4-DP, dicamba, and dursban. Beginning in 1986, plots were
treated with pesticides and fertilizers four times annually as
- Pendimethalin for pre-emergence control of annual grassy
weeds, plus a complete, soluble fertilizer.
- Early summer
- 2,4-D, 2,4-DP, and dicamba for postemergence control of
broadleaf weeds, plus urea fertilizer.
- Late summer
- 2,4-D, 2,4-DP, and dicamba plus chlorpyrifos for the control
of insect pest species, plus urea.
- 2,4-D, 2,4-DP, and dicamba plus urea.
Irrigations were conducted approximately one week before and two
days after each chemical application in order to produce runoff
and leachate samples for analyses of pesticide and nutrient
concentrations. Duration was typically 90 minutes for
pre-application events and 60 minutes for post-application
events. In addition, all natural precipitation events were
monitored for the occurrence of runoff and percolate.
Water samples were collected immediately following precipitation
or irrigation events for subsequent processing and storage.
Turfgrass quality parameters (color, cover, weeds, and overall
quality) were visually estimated periodically throughout the
growing season to document the development of the turfgrass, and
to determine whether stand quality was related to overland flow.
Total vegetative cover was determined as a percent of the total
area covered by vegetation (as opposed to stand density counts),
and reflects the amount of exposed soil associated with each
treatment. Weeds were also assessed as a percent of the total
area covered by weed species (not as a percent of the total
Runoff was much lower than anticipated regardless of
establishment method. Runoff from sodded slopes was so low that
from 1985 to 1986 the irrigation system had to be redesigned to
deliver six inches per hour instead of three inches per hour.
This change was required to develop hydrographs and provide
subsamples for nutrient and pesticide analyses. The likelihood of
six inches of natural precipitation occurring in central
Pennsylvania is extremely remote. In addition, this simulated
storm was imposed 48 hours after the application of fertilizer
Three years after establishment, slopes that were sodded still
had significantly less runoff than those that were seeded. When
infiltration rates were measured, sodded slopes had significantly
higher rates than those that were seeded. It was concluded that
sodding, as an establishment technique, provided protection for
the surface soil structure. Rainfall and irrigation that fell on
the site during establishment compacted the surface of seeded
slopes, and this effect has persisted throughout the study.
Certainly, other factors (stand density, thatch, species
differences, etc.) contributed to the runoff differences.
The effect of nutrient and pesticide transport in water is
largely a function of ambient concentrations of these potential
contaminants and the sensitivity of non-target species. These
data provide evidence of the relative transport potential of
eight nutrients and pesticides, and should also be useful in
predicting transport properties of chemically similar substances.
This research did not define the interaction of each compound
with the various environmental factors that affect the eventual
fate of a given material. The rates of transport of the nutrients
and pesticides examined in this study were very low, however,
especially considering the amount of irrigation used to produce
runoff. In addition, the transport calculations were based on
concentrations determined for the treated site.
As a point of reference, U.S. Public Health Administration
drinking water standards and measured concentration frequency
data are shown in Table 1. The dilution effect of runoff
occurring from impervious areas in actual watershed circumstances
was not considered. Actual stormwater outfall concentrations of
these pesticides and nutrients would be significantly less than
the levels found in this study. It should be noted also that in
almost all cases where pesticides were detected, the levels were
lower than what is allowed in drinking water.
Federal Drinking Water Limit
Number of Sample Dates
Number of Dates Not Detectable
Number of Dates Below Drinking Water Limit
To the degree that the site employed for this project is
representative of other turfgrass sites in central Pennsylvania,
the impact of well-managed turfgrass on water quality appears to
be positive in nature, based on the hydrologic characteristics of
all three cover types and establishment methods studied. The
results indicate that dense, high-quality turfgrass stands,
regardless of establishment method, affect the oversland flow
process to such a degree that runoff is insignificant. The
ability of this type of vegetative community to allow water to
infiltrate and promote the metabolism of solutes suggests it
might possess the ability to be employed as a water quality
Establishment and maintenance of turfgrass of high quality is not
realized without management inputs, which include quality
construction techniques, limited use, and cultural requirements,
including nutrient and pest management. Levels of management
inputs required to produce the turf quality necessary for
positive water quality impacts have not been determined. The
range of uses and existing conditions for already established
sites illustrates the complexity of the situation.
It is probably safe to assume, though, that many poor-quality
turfgrass areas are not recipients of sound, professional
management. Although these sites may not exhibit the infiltration
capacity of high-quality turf, nutrients and pesticides are less
likely to have been used on them.
Last, much of the highly managed turfgrass in the United States
is maintained in regions of varying degrees of urbanization.
Considering the magnitude of runoff contributed by impervious
surfaces, and the fact that treated turfgrass acres in those
watersheds constitute only a portion of the pervious fraction of
the landscape, dilution of low-level spikes of nutrients and
pesticides would certainly occur. Acceptable background levels of
these materials in surface water have not been determined. It is
likely, however, that their concentrations in stormwater and
impact on receiving bodies of water would be considerably less
than other urban pollutants not associated with well-managed
This research project was funded in part by: US. Geological
Survey, College of Agriculture/ Penn State University, and
Pennsylvania Turfgrass Council.
Not too long ago, construction of a golf course was considered to
be an ecologically sound and practical use of land. It often
preserved green space in otherwise intensely developed sites, and
provided a recreational opportunity convenient to residents. Golf
courses were an extremely popular and environmentally harmonious
component of the suburban/urban ecosystem.