Off the Record: Can a golf course function without pesticides?

By |  April 20, 2023 0 Comments

In the 1980s and ’90s, several communities demanded golf courses use fewer or no pesticides. Yet golf course superintendents faced with constraints on the use of pesticides had little information on how to maintain acceptable playing conditions.

Those advocating for pesticide restrictions weren’t aware of the costs associated with implementing the policies and the resulting impacts on golf turf performance.

For those reasons, Frank Rossi, Ph.D., and Jennifer Grant, Ph.D., at Cornell University, designed a project to investigate the feasibility and performance of putting green turf managed using integrated pest management (IPM) systems or no chemical pesticides.

Rossi and Grant conducted research at Bethpage State Park on the Green Course in Farmingdale, N.Y. This course accommodated approximately 50,000 rounds annually with heavily topdressed push-up soil greens six years before the project.

The research duo used 18 putting greens to design a 3-by-2 factorial, with three pest management and two cultural management regiments.

Pest-management greens received one of three regiments:

  1. Unrestricted: All legal chemical pesticides in New York were available for use.
  2. IPM: Practices determined by the specific needs of each green, based on scouting information, action thresholds (when feasible) and site history. While this regiment allowed for pesticide applications, researchers emphasized biological approaches.
  3. Nonchemical: This regiment did not allow for EPA-registered pesticides. Researchers emphasized biological approaches to prevent and minimize problems.

Cultural-management greens received one of the following regiments:

  1. Standard: The standard cultural practices employed at the Bethpage State Park golf courses.
  2. Alternative: A modified version of standard practices to reduce turfgrass stress and minimize pest problems while maintaining minimum performance standards (quality ratings above six on the NTEP rating scale).

The results

This on-course research on putting greens taught us an important lesson. First, IPM greens received 27 to 46 percent fewer pesticide applications than standard, unrestricted pest-management greens.

Dollar spot was the predominant pest problem in all years, but incidence and severity dropped in 2002 and 2003. On the other hand, Rhizoctonia incidence was higher in 2002 and 2003 than in 2001.

After the first season, the team lost nonchemical greens that received alternative cultural practices. Researchers resodded those plots with 9-month-old velvet bentgrass (SR 7200).

In 2002, researchers conceded they could not maintain acceptable conditions for nonchemical and standard cultural greens.

Therefore, those three greens received alternative cultural practices comparing traditional Poa/bentgrass greens and velvet bentgrass greens with nonchemical pest management.

Velvet bentgrass greens outperformed Poa annua/bentgrass greens without pesticides for most of 2002 and parts of 2003. Nonchemical Poa/bentgrass greens were marginally acceptable or below acceptable quality during much of July, August and sometimes early September.

In 2002, alternative greens performed better than standard cultural greens in all treatments. They used fewer pesticides to maintain alternative greens than the IPM and nonchemical strategies.

However, this did not occur in other years with higher disease pressure. Nonchemical standard greens needed an emergency chemical fungicide application in 2002 and several in 2003.

The study shows a nonchemical putting green program for creeping bentgrass greens was not practical at the time of the research. At best, implementing an IPM program and adjusting cultural practices could reduce pesticide use compared to a calendar-based program.

Photo: Mike Kenna, Ph. D.

Photo: Mike Kenna, Ph. D.

Mike Kenna, Ph.D., retired director of research, USGA Green Section. Contact him at

This article is tagged with , and posted in Columns, From the Magazine

Post a Comment