Influence of period of deferment before stocking spring‐burnt sourveld on sheep performance and veld productivity

Abstract

Spring‐burnt sourveld was stocked with Merino lambs after three different periods of deferment from the time of start of growth in spring. During three seasons, average seasonal livemass gains on veld which was stocked shortly after the start of growth were some 80% higher than on veld stocked two to three weeks later. Using veld from which grazing was excluded by means of exclosure cages as a control, the residual effects of the deferred grazing treatments on yields of grasses classified as palatable, intermediate or unpalatable were estimated in the next season. Deferring grazing in spring was of negligible value in preventing loss of vigour of the palatable grasses. The respective yields for the three classes were on average for three seasons, 57, 101 and 144% of those for the controls. The findings indicate the need for drastic revision of current recommendations with regard to the management of sourveld for sheep production.