Nitrogen and phosphorus fertilization of forage oats in the Maranoa region of southern Queensland

Abstract

Six rates of nitrogen (0, 10, 20, 40, 80 and 160 kg N ha-1) and four rates of phosphorus (O, 7.5, 15 and 30 kg P ha-1) were applied to oats at planting in a full factorial design on six sites during 1973 and 1974. Prior to planting, the nitrate-nitrogen concentrations in soil (0 to 20 cm) varied from 4 to 44 ppm and 'available' phosphorus (bicarbonate method, 0 to 10 cm) varied from 6 to 34.5 ppm; soils ranged in clay content from 17 to 58%.