A note on the effects of paddock size on the white clover content of swards grazed by sheep

Abstract

The maintenance of a high white clover content in mixed swards under sheep grazing has been a challenge to date. This paper presents the results of an experiment in which the effect of the length of a grazing period on the botanical composition of a mixed sward was studied. Paddocks ranging in size from 0.014 to 0.133 ha were rotationally grazed by a flock of seven dry ewes. Consequently, grazing periods ranged from 1 to about 8 days. On all paddocks, the proportion of perennial ryegrass declined progressively during the grazing season, regardless of paddock size. The proportions of both white clover and creeping bentgrass content increased on all paddocks during the same period. For white clover, the size of the increase was negatively related to paddock size, whereas a positive relationship was found between the paddock size and the magnitude of the increase in creeping bentgrass. This suggests that the proportion of white clover may be increased under sheep grazing by implementation of strip-grazing.