Delaware’s golf course superintendents are dedicated to protecting the state’s natural resources. As a demonstration of this commitment, superintendents have partnered with University of Delaware scientists to develop and document best management practices (BMPs) for golf course management. These research-based, voluntary guidelines developed specifically for the state of Delaware, in addition to the state’s nutrient and pesticide regulations, not only protect natural resources, they also afford the opportunity for superintendents to be recognized by club members, the public, and state officials as environmental stewards.
Golf courses, especially in urban areas, often represent some of the largest areas of open space around. These large expanses of grass, shrubs, and trees allow water to infiltrate into the ground naturally instead of flowing into storm sewers. This is an example of an ecosystem service that benefits humans and other species directly and indirectly. Other ecosystem services linked to large expanses of turf, like those found on Delaware’s golf courses, include temperature moderation, stormwater management, cultural services such as recreation, and supporting services such as nutrient cycling, water cycling, and provisioning of habitat.
1.1 Key Components of Delaware’s Golf Course BMPs
BMPs are methods or techniques found to be the most effective and practical means of achieving an objective, such as preventing water quality impacts or reducing pesticide usage. Because of the efforts aimed at protecting water quality, especially in the portions of Delaware located within the Chesapeake Bay watershed, the majority of BMPs in this document relate to water quality. In addition, an emerging concern related to protecting pollinators is also addressed, including identifying specific practices to protect pollinator health as well as expanding habitat for pollinators. Priority topics addressed in this document include the use of nutrients and pesticides, the potential for erosion and sedimentation, water conservation, and emerging concerns related to pollinators. Each area is described briefly below and addressed throughout this document.
1.1.1 Nutrient and Pesticide Usage
The proper use of nutrients and pesticides promotes healthy plant growth which then promotes ecosystem health. When applied properly and in the correct amounts, nutrients are taken up by plants and create a dense, healthy turf that resists diseases and weed encroachment. When properly applied, pesticides are directed to and absorbed or taken up by the target. For example, foliar applied sprays are absorbed by plant leaves, while soil-applied pesticides may be taken up by plant roots. Once in plant tissue, pesticides may be broken down. However, the components of fertilizers (nitrogen and phosphorus) and characteristics of pesticides (toxicity, solubility, and chemical breakdown rate) can impact water quality and non-target species through off-site movement and exposure.
Best management practices reduce the potential for water quality impacts from fate and transport mechanisms such as runoff, leaching, and drift. For example, nutrient BMPs describe the appropriate amounts of fertilizers that should be applied and when they should be applied to maintain a healthy turf and plants without over-fertilizing. Maintaining vegetated buffer strips along waterways, a key BMP, allows for the deposition of nutrients, pesticides, or sediment in vegetation before reaching a waterway. Pesticide BMPs provide the necessary guidance for the proper transport, storage, mixing, and application of pesticides to address target pests and minimize impacts to non-target species.
1.1.2 Erosion and Sedimentation
Erosion is the action of surface processes that remove soil, rock, or dissolved material from one location and transport it to another. Sedimentation is the deposition of eroded material. Eroded soil and sediments can introduce pollutants into surface waters such as organic matter, nutrients, chemicals (such as pesticides), and other wastes. For example, phosphorus is immobile in most soils and concentrates in the top few inches of the soil, where it is very susceptible to erosion and thus likely to be present in sediment. Design and construction BMPs and stormwater management BMPs address the potential for erosion and sedimentation and ways to mitigate that potential.
1.1.3 Water Usage
Water is a fundamental element for physiological processes in turf such as photosynthesis, transpiration, and cooling, as well as for the diffusion and transport of nutrients. Turf quality and performance depend on an adequate supply of water through either precipitation or supplemental irrigation. Too little water induces drought stress and weakens the plant, while too much causes anaerobic conditions that stunt plant growth and promote disease. Excessive water can also lead to runoff or leaching of nutrients and pesticides into groundwater and surface water. The design and maintenance of irrigation systems, as well as proper irrigation scheduling, careful selection of turfgrass cultivars, and incorporation of cultural practices that increase the water holding capacity of soil are addressed through these BMPs.
Protecting bees and other pollinators is important to the sustainability of agriculture. Minimizing the impacts of pesticides on bees and other pollinators, as well as beneficial arthropods, is addressed in this document in two ways: (1) by promoting the use of integrated pest management (IPM) methods to reduce pesticide usage and minimize the potential of exposure when pesticides are needed and (2) by providing specific guidance for pesticide applicators to follow when chemical control is needed. Superintendents can also directly support healthy pollinator populations by providing and/or enhancing habitat for pollinator species and supplying food sources, nesting sites, and nesting materials.
1.2 Using this Document
This document was developed using the latest science-based information and sources. As of the time of this printing, the information was the latest available; however, the reader should make an effort to identify the latest version. In addition, regulations may change and the reader should make an effort to identify any changes.