Best Management Practices for Maryland Golf Courses

Nutrient Management

Elevated levels of nitrogen (N) and phosphorus (P) have been identified as major contributors to the decline of the health of the Chesapeake Bay. Potential sources of leaching and runoff of N and P include fertilization of landscapes. However, properly fertilized and maintained turfgrass on golf courses has minimal impact on elevating N and P levels of ground or surface water. In addition, as discussed in the following section on regulations, state laws regarding fertilizer applications specify how N and P may be applied to turfgrass in Maryland, including golf courses. Proper nutrient management plays a key role in the reduction of environmental risk and increases course profitability. Among other benefits, applied nutrients allow turfgrass to recover from damage, increase its resistance to stress, and boost its playability. The goal of a proper nutrient management plan should be to apply the minimum necessary nutrients to achieve an acceptable playing surface, to apply nutrients in a manner that maximizes their uptake, and to maintain turfgrass density and its associated environmental benefits.

Regulatory Considerations

Nutrient management regulations passed by the Maryland Legislature in 1998 require that the University of Maryland nutrient management guidelines be followed on state property and commercially managed turfgrass sites, including golf courses. In 2011, additional regulations further specified how N and P can be applied to turfgrass sites, as well as requiring state training and certification of nutrient applicators. These regulations became effective in 2013 and limit application of fertilizers as follows:

Maintenance N and P Fertilizer Applications

• Water soluble N fertilizers are limited to 0.7 pounds actual N per 1000 ft 2 per application. • Slow release N fertilizers are limited to 0.9 pounds actual N per 1000 ft 2 per application. • Fertilizers classified as an enhanced efficiency N fertilizer are allowed up to 2.5 pounds actual N per 1000 ft 2 , as long as 80% of the annual rate for a given turfgrass species is not exceeded. • Between December 1 and March 1, N fertilizers cannot be applied to golf course turf. • Between November 15 and November 30, 0.5 pounds actual N per 1000 ft 2 can be applied, but only using a soluble N source. • P applications must be based on soil test recommendations; however, P cannot be applied between December 1 and March 1. • N or P fertilizer applications cannot be applied to impervious surfaces such as walkways, driveways, and roadways. Any fertilizer that lands on impervious surfaces must be removed or returned to the turf, such as by sweeping or blowing. • Fertilizers containing N or P cannot be applied to frozen ground, regardless of the date • No fertilizer containing N or P can be applied within 15 feet of specified waterways. If a drop spreader, rotary spreader with a deflector plate, or a targeted liquid spray is used for applications, then fertilizer can be applied no closer than 10 feet from such waterways.

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