Reduced Pesticide Research USGA

Reduced Pesticide Research USGA

Evaluation of Golf Turf Management Systems with Reduced Chemical Pesticide Inputs.

By Jennifer A. Grant and Frank S. Rossi, Cornell University

Start Date: 2001
Project Duration: 3 years
Total Funding: $87,000


This project was designed to provide information on the feasibility and performance of golf course putting green turf managed with few or no chemical pesticides, and is being conducted on the Green Course at the Bethpage State Park, Long Island, NY. Current golf course pest management practices ("unrestricted") have been compared with IPM and nonchemical management for three years. Further comparisons have been made between standard cultural practices and "alternative" practices that we believe reduce turfgrass stress and thereby minimize pest problems. The project explores total management systems, as practiced by turf managers, rather than focusing on individual technologies and isolated practices.

Management and Evaluation:

Alternative cultural practices included mowing at 3.3 - 4.7 mm (0.130 - 0.188 in), increased N rate and use of organic N sources, frequent hydrojecting and vertical mowing, reduced frequency of clean-up passes, and hand watering of known dry spots prior to wilting. The nonchemical greens performed poorly in the first season. Therefore, the three alternative culture greens were subsequently converted to velvet bentgrass (SR 7200), a disease resistant species. For pest management, cultural and biological practices were employed specifically to prevent or reduce pest problems on some or all of the nonchemical and IPM greens.

In 2003, we buried these greens under a layer of brewery-waste compost for the winter to suppress snow mold and build populations of beneficial microbes; kept fertility levels high to aid recovery from dollar spot injury; applied several biological or alternative products for disease management including EcoGuard™ (Bacillus licheniformis ), Allude™ (phosphite product), and Endorse™ (Polyoxin-D, derived from fermented Streptomyces cacaoi); and removed weeds manually.

Results Dollar spot was the primary pest in all treatments and was the target of most pesticide applications throughout the study. However, its annual incidence decreased in all IPM and nonchemical treatments. Other pests of significance in 2003 included brown patch, rhizoctonia, fairy ring, summer patch, black cutworm and goosegrass. Compost applications likely increased the population of beneficial microbes in IPM and nonchemical greens and may have contributed to reduced dollar spot incidence. However, the winter compost covers left layers in the soil profile, and were associated with damaging fairy ring infestations and a high incidence of rhizoctonia.

Over the three years, IPM greens received 29-46% fewer pesticide applications than the unrestricted greens, with the greatest reductions in the second year of the study. Quality of the IPM greens equaled that of the unrestricted greens for most of the study, with exceptions in the first and third year. In the nonchemical treatments, the velvet bentgrass greens performed better than their counterparts, but were occasionally below acceptable quality. The poa/creeping bentgrass greens in the "nonchemical" pest management treatment were often of unacceptable quality and received an emergency pesticide application in 2002, and several in 2003. In 2002, quality of the alternative culture greens was usually higher than their standard culture counterparts in all treatments, and they received fewer pesticide applications. However, differences were less pronounced in the first and third year. In 2003, we utilized more biological and reduced-risk pesticides, but had less labor. Staffing concerns forced significant alterations of cultural practices, but project integrity and treatment separation were not compromised.



The range of results over the three years of the study reflect the variation of environmental conditions. In a wet year like 2003, cultural and biological methods for disease suppression are less effective. In the Northeast, poa/creeping bentgrass greens are highly susceptible to disease and stress pressure in July and August. Management with few chemical pesticides continues to be a challenge during these summer months, with these turfgrass species. From what we have learned to date, we believe that pesticide use can be significantly reduced in some years, without compromising quality. However, research is still needed to develop tools and knowledge to deliver consistent and reliable results with few or no chemical pesticides.

Summary Points

• The nonchemical greens performed poorly in the first season. Therefore, the three alternative culture greens were subsequently converted to velvet bentgrass (SR 7200), a disease-resistant species.
• Dollar spot was the primary pest in all treatments and was the target of most pesticide applications throughout the study. However, its annual incidence decreased in all IPM and nonchemical treatments.
• Over three years, IPM greens received 29-46% fewer pesticide applications than the unrestricted greens, with the greatest reductions in the second year of the study.
• The Poa/creeping bentgrass greens in the "nonchemical" pest management treatment were often of unacceptable quality and received an emergency pesticide application in 2002, and several in 2003.
  

2003 USGA Turfgrass and Environmental Research summary.

Reproduced with kind permission of USGA Turfgrass and Environmental Research Program.

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