The Major Megetation Types (MVT) and plant communities of the Soutpansberg Centre of Endemism are described in detail, with special reference to the Soutpansberg Conservancy and the Blouberg Nature Reserve. Phytosociological data from 442 sample plots were ordinated using a DEtrended CORrespondence ANAlysis (DECORANA) and classified using TWo-Way INdicator SPecies ANalysis (TWINSPAN). The resulting classification was further refined with table-sorting procedures based on the Braun–Blanquet floristic–sociological approach of vegetation classification using MEGATAB. Eight MVT’s were identified and described as <em>Eragrostis lehmanniana</em> var. <em>lehmanniana–Sclerocarya birrea</em> subsp. <em>caffra</em> Blouberg Northern Plains Bushveld, <em>Euclea divinorum–Acacia tortilis</em> Blouberg Southern Plains Bushveld, <em>Englerophytum magalismontanum–Combretum molle</em> Blouberg Mountain Bushveld, <em>Adansonia digitata–Acacia nigrescens</em> Soutpansberg Arid Northern Bushveld, <em>Catha edulis–Flueggia virosa</em> Soutpansberg Moist Mountain Thickets, <em>Diplorhynchus condylocarpon–Burkea africana</em> Soutpansberg Leached Sandveld, <em>Rhus rigida</em> var. <em>rigida–Rhus magalismontanum</em> subsp. <em>coddii</em> Soutpansberg Mistbelt Vegetation and <em>Xymalos monospora–Rhus chirendensis</em> Soutpansberg Forest Vegetation

Congo red was found in this research to form colloidal complexes with di-and tri-valent cations in the presence of acid and alkali. The complexes formed at a pH of 2–3 were uniformly blue; those formed at a pH greater than 12 varied in color with the ion involved, a fuchsia complex being formed with magnesium. The congo red reaction in bacteria (e.g. coloration of the growth in media containing the dye) is explained as due to the adsorption of Congo red on the surface of the bacterial cell, to the ions which predominate at the surface, and to the production of acid or alkali by the bacterium during growth. The temperature of incubation and composition of the growth medium influence colony coloration by affecting the metabolism of the organism.A negative form of selection for rhizobia is suggested using a nitrogen-deficient and a nitrogen-rich carbohydrate medium containing 0.25 g Congo red per liter of agar and 0.025 g Congo red per liter of broth, with incubation at 28 °C and 37 °C respectively. Color differentiation among the rhizobial strains tested, four normal and seven mutant varieties of Rhizobium meliloti and Rhizobium trifolii, occurred on the nitrogen-rich agar medium when incubation was carried out at 25 °C to 28 °C.

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It has been estimated that approximately 30% of the grassland biome of South Africa has been permanently transformed. An account of the demise of these high rainfall grasslands of the Soutpansberg, which occurred on soils derived from weathered basalt using historic accounts and photographic records, is given. This article also strives to quantify the extent of these extinct high rainfall grasslands using the concept of a climatic N-value in correlation with the underlying geology of the area. Historic as well as photographic records show the rapid demise of these grasslands with the main period of transformation occurring between the 1920s and 1950s. Modelling the extent of the extinct grasslands using a combination of basalt distribution and climatic N-value has shown that they covered approximately 10% of the Soutpansberg. Regional habitat change in combination with overexploitation has led to the localised extinction of 14 mammalian herbivore species, nine of which were specialised grazers. The contributing factors to the demise of these grasslands are complex and usually entail an interaction of various influences. Most of these contributing factors are as a direct result of anthropogenic activities.