What We’ve Learned From a Decade of Reducing Pesticide Use

Frank S. Rossi, Ph.D. and Jennifer A. Grant, Ph.D. Cornell University

The golf course industry has been under scrutiny for pesticide use in NY for more than 25 years. The publication of “Toxic Fairways; Risking groundwater contamination from pesticides on Long Island golf courses” in 1991 inflamed the debate that would culminate a decade later in landmark legislation proposed to ban pesticide use on municipal golf courses in Suffolk County.

 In response to the proposed legislation and concern this could spread to other counties, a systems-based research project was initiated at the Bethpage State Park-Green Course to accomplish two primary goals. The first goal was to develop putting green management systems (cultural and pest) that would reduce reliance on synthetic chemical pesticides and second to demonstrate the impact of a pesticide ban on golf turf performance.  

The project has two operating principles. The first principle is to alter the conventional cultural management program into an alternative approach that would reduce stress and thereby reduce pesticide use. Secondarily, we knew that there were many potential products that could be used to reduce synthetic chemical use, however we learned very few had research based information to support their use. In short, most products had no research and the few that did showed very little promise.

Systems Research  
The project began in the 2000-growing season as a systems-based project. Systems-based research does not focus on individual products or practices. In fact, in systems research, a treatment is a collection of products or practices designed to achieve a particular goal with a particular emphasis. An example of a systems approach is dieting, e.g., with the goal of losing weight you could use Nutri-system, Weight Watchers, Atkins, etc. In the end, you eat all sorts of different foods in each diet with a goal to lose weight. The cultural and pest management systems included different practices and products that met the treatment criteria.  

The project established two cultural management systems, conventional (what most golf courses are doing) and alternative (experimental and what might lead to reduced stress). In each case, the goal was to maintain acceptable visual quality and maintain ball roll distances in the 8.5 to 9.5 ft. range.  

Over the years, we learned much about the various cultural systems.  For example, we learned mowing heights below 0.120” created significant stress and mowing height above 0.150” often resulted in more dollar spot and significant reductions in ball roll distances. We learned we could roll much more than 3 days per week and skip mowing. We have not applied any other nutrients other than nitrogen and iron to the alternative greens in the 12 years of the experiment and plants look great!

The same systems approach held for the pest management programs where the three programs were conventional program, progressive IPM program, and a completely non-chemical program as specified by the pending pesticide law. After the first two years, six greens in the non-chemical program failed resulting in more than 90 percent turf loss. Therefore, the non-chemical treatment evolved to be bio-based reduced-risk pest management focusing on using biological and reduced risk products that might sustain the greens while aspiring to greater environmental compatibility.

What We’ve Learned about Golfers  
Each year of the experiment, we survey the golfers on the course asking them about visual and playing quality of the greens as well as their thoughts about pesticide use on the golf course. We’ve learned that most golfers want acceptable visual quality and want them to putt true. Few complained about minor blemishes but did not like temporary surfaces when the regular green failed.  

In general, golfers do not worry much about pesticides. In fact, there is a recent trend in the data that they want good playing conditions regardless of how much pesticide needs to be used. This is a shift away from using pesticides judiciously.  Invariably, golfers think they are able to play much better than they actually play and often take this frustration out on the course and staff. In general, golfers cannot detect differences in ball distance unless they are 1 foot or greater. Interestingly, we have found that when they have more uphill putts they think the greens are slower and more downhill putts they think the greens are faster.

What We’ve Learned about Non-Golfers  
The motivation behind reducing pesticide use clearly comes from the more than 80 percent of the US population that does not play golf. No question, non-golfers dislike pesticide use on golf courses, but in many cases, simply abhor the land use, perceived elitist, expensive, perceived conservative aspects and simply hate golf.  

A major subset of non-golfers includes policy-makers. A primary goal of this project was to inform policy-makers about the consequences of pesticide bans. In the first few years of the project, field days were held for policy-makers and aides to view the results to date. These meetings had profound impact on pesticide legislation and while the debate has not ended for golf course pesticide use, many have recognized the use of pesticides for sustaining the economic aspects of golf.

What We’ve Learned About Course Maintenance Staff  
By far, the most rewarding part of this 12 year project has been our involvement with the staff at the Bethpage State Park. From Dave Catalano and Craig Currier to Andy Wilson and Kathy Wegman, the level of professionalism and commitment to the project has been second to none. That said there were many growing pains.

Often the research would push the envelope in terms of making major changes in programs. At first, they were met with the appropriate level of skepticism and then over time as some success was found, or failure noted, a practice or product would either be dropped or further implemented.  

The staff evolution would be typical of any course that embarked on this type of endeavor where challenging the status quo, or something that always worked in an effort to reduce reliance on pesticides. We have many examples of products or practices that would be dismissed only to emerge again as vital aspects of the program. For example, the Field Scout 300 moisture meter initially gathered dust on a shelf and then became a go to tool for improving irrigation programs.

What We’ve Learned About Alternative Products  
When the project was initiated, there were few real alternative chemical pesticides that had demonstrated any meaningful performance. Some of the lack of efficacy was the way the products were tested in that often they do not work under high pest pressure. Still, most products simply over-reached and did not work.  

As the project has progressed, our Cornell University Turfgrass Program began generating data as did other Universities on alternative products. This data continued to weed out non-performers but also suggested that many products could be used in conjunction with existing pesticides to reduce overall rates or extend intervals. This has been particularly true for Civitas that has reduced reliance on many products altogether and especially allowed for reduced use rates.  

While not alternative, the elimination of most fertilizer nutrients except N and iron has been the most eye opening. Soil testing data continues to reveal changes and in some cases, increases even in the absence of any application. This has been especially true for potassium, phosphorus and calcium. All levels have declined dramatically and yet there is no evidence the plants are suffering. We’ve learned we need to rethink our obsession with turfgrass nutrition. It’s important but don’t let it get distracting.

What We’ve Learned About IPM  
This project has redefined IPM. For many it cost too much, took to much time, meant they could not spray, etc. Now with the publication of our new IPM Manual (available in English and Spanish), many misconceptions can be addressed with data and results from this study.  

We no longer need to adhere simply to thresholds as we develop site history. Often preventative applications of more environmentally compatible products are better than waiting for an outbreak and needing harsher products.  Traditional thinking was used as well to improve growing conditions such as light and soils. Clearly the commitment to a more permeable rootzone in old push up greens is critical to the success of  the project. Excess water is a death nail.  

The deep integration of the Environmental Impact Quotient into day-to day management as means of assessing the environmental impact of products and programs has allowed for greater flexibility in developing pest management programs. In the end, the pesticide reduction we have seen is related to the lower environmental impact, not necessarily how much we spray.

Frank Rossi gets close to his work at Bethpage Black. Image courtesy Frank Rossi.

What We’ve Learned About Moving Forward  
Moving forward, we have begun implementing these concepts and practices on all 27 NY State Golf Courses. Also, the project transitioned nicely to include fairways and tee areas and this is where significant reductions can be found. For example, after 10 years of pre-emergence crabgrass herbicide use on fairways we have begun skipping these applications. We learned that we are able to skip at least two to three years before some turf loss allowed for crabgrass to reinvade.  

This project has taught everyone associated with it the power of working together in the face of adversity and with limited tools to attempt to improve resource efficiency. The recent economic downturn has impacted golf and now many are seeking means to reduce costs. Clearly there are opportunities to reduce some costs of fertilizer and pesticides.  

The golf turf industry should embrace the ideas of improved efficiency and develop products and practices that can be sustained. I doubt the Bethpage Project will answer all the questions, but certainly we think we have begun to layout a clear direction for golf as our neighbors to the north in Canada are facing severe restrictions.  

We learned there are answers out there if you are willing to break from conventional wisdom and take small steps for change. Sometimes when your hands are tied you can reach for what you want.