Inter‐related floristic changes associated with different long‐term grazing treatments in Sourish Mixed Bushveld¹

Abstract

Eight camps, grazed annually during different seasons by steers, were surveyed. Herbaceous species were grouped into Decreaser and Increaser categories according to their reaction to grazing. The Increaser IIa (light overgrazing) and IIb (moderate overgrazing) herbaceous species were the most abundant and were significantly negatively correlated. Woody plants and aloes (Aloe transvaalensis) were positively correlated (P≤0.01) with Increaser IIb herbaceous species. The latter were negatively correlated (P≤0.01) with grass production. The production of Panicum maximum was negatively correlated (P≤0.01) with tree canopy cover, owing to its intolerance to severe grazing which contributed to an increased canopy cover. While representing the same amount of animal unit grazing days ha⁻¹ (stocking density × period of occupation during growing season), a relatively high stocking density and occupation for part of the growing season had a less severe long‐term effect on the floristic composition than a relatively low stocking density and occupation for the whole growing season.