Phosphorus in herbage grasses - prospects of reducing fertiliser phosphate requirements

Abstract

Previously published results show that herbage grasses vary in the severity with which they compete with white clover (Trifolium repens) for soil phosphorus. It is argued that grasses such as 'Grasslands Matua' prairie grass (Bromus willdenowio with lower herbage phosphorus concentrations than ryegrass, will maintain better productivity and clover contents in the sward as phosphate fertiliser rates are reduced, than a comparable ryegrass sward. Apart from prairie grass, there seems to be little variation in herbage phosphorus levels in current 'Grasslands' forage grasses and screening for reduced levels is advocated. Keywords Bromus willdenowii, competition, cultivars, grasses, herbage, Lolium perenne phosphate, phosphorus, superphosphate.