Macronutrient and Boron Ratios in Tall Fescue: Relationship to Yields on Pyritic Coal Wastes

Abstract

AbstractA previous greenhouse study had demonstrated that yield of tall fescue (Festuca arundinacea Schreb.) grown directly on a pyritic waste was not significantly different from yield on a soil despite low tissue concentrations of P and K in the waste‐grown plants. In an attempt to explain this result, and to determine if this phenomenon was typical of such wastes, a greenhouse study was carried out with pyritic wastes from five disposal sites for coal‐cleaning refuse in southern lllinois. The wastes and an agricultural soil (Elliott silt loam: fine, illitic, mesic Aquic Arguidolls) were treated with limestone (to pH 6.5) and fertilizers. Yields of 8‐week‐old shoots of tall rescue grown on the wastes were significantly lower than yield of plants grown on the soil when the Ca/B ratio in the shoots was outside a range of 1.7 to 2.8 (where Ca/B is the ratio of log10 concentrations of Ca and B expressed as microgram‐atoms per gram dry matter). Within this range, yields were not significantly different from yield on the soil despite significantly lower concentrations of P and K in the shoots of the waste‐grown plants. It is suggested that elemental interactions should not be ignored in reclamation of waste sites, particularly where “trace” element concentrations are either higher or lower than concentrations in typical soils. Results also suggest a P‐ and K‐sparing effect of elevated B concentrations in tall rescue.