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Grass communities identified through association-analysis were used for determining the effects of several methods for eradicating and controlling macchia. Follow-up burns at three frequencies applied over a ten-year period to control macchia were found to have masked most differences in species composition of the grass sward which may have arisen as a result of eradication treatments of burning, spraying and cutting. However, Elyonurus argenteus Nees and Harpechloa falx (L.) Kuntze were absent only from stumped plots. Themeda triandra Forsk. and Apochaetae hispida (L.f.) Phipps survived in a vegetative stae in unburned, control plots for about 20 years in spite of competition from a dense, bushy growth of macchia (Cliffortia paucistaminea H. Weim., C. linearifolia Eckl. & Zeyh. and Erica brownleeae Bolus). Themeda triandra was best adapted to withstand frequent burning while Heteropogon contortus (L.) Beauv. ex Roem. & Shult. was suppressed by this treatment. Certain other grasses may have survived entirely below the soil, and without evidence of aerial portions, in moribund veld. Basal cover was used for recommendations on veld burning management, whether for purposes of water production or for grazing.Keywords: amatole mountains; apochaetae hispida; association analysis; basal cover; botanical composition; burning; cliffortia linearifolia; cliffortia paucistaminea; competition; control; cutting; dohne sourveld; elyonurus argenteus; eradication; erica brownleeae; grass sward; grasses; grazing; gxulu kop; harpechloa falx; heteropogon contortus; keiskammahoek; macchia; management; method; production; south africa; species composition; techniques; themeda triandra; treatments; veld; veld burning

The variation in total basal cover from one time of year to another was investigated by means of the bridge and wheel-point methods over a period of seven years. Treatments were: a control plot, one cut annually in winter and one in spring; a fourth plot was burnt and a fifth burnt and cut alternately, in spring. Statistically significant increases and decreases in total basal cover were found between a number of consecutive surveys. Maximum basal cover was usually recorded between April and July and the minimum basal cover between July and October, although exceptions to both ranges were found. Winter and spring basal covers were significantly correlated (P = 0,001 and 0,01 respectively) with the rainfall of the preceding season on the control plot, but no correlation with rainfall was found on the treated plots. The cover of Trachypogon spicatus and Eragrostis curvula increased and decreased, respectively, with or without cutting and burning treatments, over the period of study. Themeda triandra increased in basal cover with treatments, while cover of Setaria perennis decreased. The cover of Heteropogon contortus remained fairly constant, but decreased when no treatments were applied. The various treatments gave similar results, but usually differed from those of the control. It was concluded that the best time for making an annual survey of basal cover by means of a point method is between May and June. At this time the plants may be easily identified and basal cover is at its highest.Keywords: basal cover; burning; cover; cutting; effects; eragrostis curvula; grassland; heteropogon contortus; national botanic garden; pretoria; rainfall; seasonal variation; setaria perennis; south africa; themeda triandra; trachypogon spicatus; treatments; wheel-point method