Best Management Practices for Maryland Golf Courses

metabolism and availability. Depending on turfgrass species, problems in turf may start to occur at soil pH above 7.8 and below 5.4. Thus, to maximize efficiency of nutrient availability and use, soil tests should be taken as recommended previously for soil P and K to determine soil pH.

Recommended limestone applications to achieve a soil pH of about 6.4 are available. (See Nutrient Management Guidelines

for Commercial Turfgrass Seeding . 2005. University of Maryland.) If diseases such as take-all patch of bentgrass, summer patch of Kentucky bluegrass, or spring dead spot of bermudagrass are of concern, maintaining lower soil pH (5.4 to 5.7) may be desirable, and reduced or no limestone should be applied to achieve this level. Also, it is recommended, when practical, that limestone be applied approximately one month or more before seeding to minimize potential P availability problems and the potential for volatilization loss of applied N. While these recommendations should result in satisfactory establishment in most situations, many factors can impact whether modifications of these recommendations are warranted for a specific site.

Figure 22. Summer patch of Kentucky bluegrass cultivar differences in an NTEP trial. Photo credit: Thomas Turner.

Best Management Practices

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Test soil pH as part of soil testing.

• Adjust soil pH to recommended levels for a given turfgrass species and site.

Nutrient Management Planning

Environmental conditions vary greatly in Maryland and include differences among soils, topography, rainfall, and temperature. These differences require that a nutrient management plan be flexible enough to allow turfgrass managers to address their unique needs. In addition, a site analysis of the entire course should be conducted to identify those areas most prone to potential losses or potential impacts on water systems. These include highly sloped areas, areas immediately adjacent to water, and areas with sandy soils with high water tables. Understanding the timing for the most effective use of applied nutrients is important, as is knowing the different nutritional needs of various areas of the course. Examples of different needs include the following: • Reduced height of cut and excessive traffic damage on putting greens result in an increased need for growth leading to an increase in nutrition needs. • Tees and landing areas often have higher fertilization requirements than fairways and roughs because they suffer constant divot damage. • Fairways and roughs often require lower nutrient inputs than other locations because of their increased height of cut, less damage, and clipping return. Because the use of N and P fertilizers are regulated (see Maryland fertilizer regulations ) and are of the greatest concern with respect to water quality, the application of these nutrients is discussed in greater detail below. Nutrient management guidelines are published by the

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