ABSTRACT
A three year field study was conducted on a Decatur silt loam (Rhodic Paleudult) in north Alabama. The objective of the study was to evaluate the effects of winter grazing on the K and starter fertilizer needs of cotton (Gossypium hirsutum L.). Grazed and non-grazed treatments were established by planting a wheat (Triticum spp.) cover crop in the fall and allowing cattle to graze for 35 to 65 days prior to planting using a strip-tillage system. After grazing, fertility treatments were established in the killed wheat. Fertility treatments consisted of 3 rates of K (0, 40, and 80 K2O/acre), 3 methods of K application: 1) surface broadcast, 2) in-row, band application at a depth of 12 inches, and 3) surface band application using a spacing of 20 inches and two rates of starter fertilizer: 1) no starter, and 2) 150 lb/acre of a liquid 15-15-0. Seed cotton yields were affected by grazing of the winter cover crop prior to planting but not by the method of K fertilizer application. Starter fertilizer consistently gave slightly higher yields with a significant response occurring in two out of three years.
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