Best Management Practices for Maryland Golf Courses

Potassium is generally more critical for established turf and may play a role in drought, heat, cold, and wear tolerance.

Secondary Macronutrients

Secondary macronutrients are essential to plant function and are required in quantities less than N, P, and K, but more than micronutrients. These include calcium (Ca), magnesium (Mg), and sulfur (S). Each are described briefly below: • Calcium : Primarily a component of cell walls and structure. Found in gypsum, limestone, and calcium chloride. • Magnesium : Central ion in the chlorophyll molecule and chlorophyll synthesis. Found in S-Po-Mg, dolomitic limestone, and magnesium sulfate. • Sulfur : Metabolized into the amino acid, cysteine, which is used in various proteins and enzymes. Found in ammonium sulfate, elemental sulfur, gypsum, and potassium sulfate. Understanding the role of each micronutrient within the plant should provide a greater understanding of the key role these nutrients play in proper turfgrass management. Micronutrients are just as essential for proper turfgrass health as macronutrients, but are required in very small quantities compared with macronutrients. Micronutrients include iron (Fe), manganese (Mn), boron (B), copper (Cu), zinc (Zn), molybdenum (Mo), and chlorine (Cl). • Iron : Part of the catalytic enzymes, Fe is required for chlorophyll synthesis affecting photosynthesis, nitrogen fixation, and respiration. • Manganese : Involved in photosynthesis, Mn is required as a cofactor for about 35 enzymes. Lignin biosynthesis depends on Mn. • Boron : Found in the cell wall. B is probably required for the structural integrity of the cell wall. • Copper : Cu-protein plastocyanin is involved in photosynthesis and is a cofactor for a variety of oxidative enzymes. • Zinc : Zn is a structural component of enzymes and is required for protein synthesis. Carbohydrate metabolism is affected by Zn. • Molybdenum : Mo is primarily related to nitrogen metabolism and is involved in the structural and catalytical functions of enzymes. • Chlorine : Cl is required for the oxygen-evolving reactions of photosynthesis and also appears to be required for cell division in both leaves and shoots. Micronutrients

Soil pH

Maintaining soil pH in an optimum range is important for maximizing the efficiency of nutrient use and can be important in reducing weed and disease problems. Turfgrass can withstand a rather broad range of soil pH, but 5.8 to 6.4 is generally considered ideal. Wide deviations from this range can result in reduced P and micronutrient availability and can interfere with soil N

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