The Effects of Frequency and Intensity of Grazing On The Productivity of A Pasture of Short-Rotation Ryegrass and Red and White Clover

Abstract

An experiment is described in which the effects of four combinations of frequency and intensity of grazing on the productivity and species yields of a pasture of short-rotation ryegrass and red and white clover were determined over a two-year period. Annual herbage production was highest under long spelling. Annual yields were also high under frequent light grazings, but were markedly less where the grazings were severe. The growth of ryegrass was favoured by long spelling between grazings. Red clover yielded equally well under long spelling or frequent grazings, provided the grazings were not severe. White clover yields were highest under frequent grazing. The most marked treatment effects on productivity were recorded in periods of low pasture production. Over the late summer and autumn, yields were highest where frequent hard grazings did not occur; but, during the winter, yields were highest in the grazing systems that favoured ryegrass growth, or where losses of herbage through tissue decomposition were avoided. The results are discussed in relation to the differential effect of temperature, light, and moisture supply on growth and botanical composition, as influenced by the different frequencies and intensities of grazing. || ABSTRACT AUTHORS: Auth. summ