The effect of grazing interval on the composition and productivity of a perennial ryegrass‐white clover sward

A ryegrass‐white clover sward was grazed by Welsh Mountain ewes with single lambs at a stocking rate of nineteen ewes per ha from April until October. Rotational grazing was practised and the treatments compared were rest periods of 3, 4 or 5 weeks. The percentage of ground covered by clover was estimated visually and quadrats were also cut to ground level to estimate the amount of clover dry matter present. A good correlation was obtained between these two estimates. Although the sward contained about 20% clover on visual assessment, the dry matter contribution was small. The amount of clover increased slightly over the season on all treatments, but the different rest periods of 21, 28 and 35 d made no significant difference to the amount of clover present. The growth rate of the lambs was also not significantly different between treatments.