The vegetation supported by the Witteberg and Dwyka Groups south of
Worcester is a diverse mosaic of fynbos-, renosterveld- and succulent karoo
vegetation units sustained by a winter-rainfall pattern. Elytropappus rhinocerotis
(renosterbos) dominated plant communities are found on finer grained soils
derived from the various mudrock-dominated formations of the Witteberg
Group, a Passerina truncata (gonnabos) dominated shrubland with large Protea
shrubs and / or small Protea trees where the substrate is largely influenced by
the sandstone-dominated formations of the Witteberg Group, a grass
dominated Capeochloa arundinacea (Olifantgras) shrubland where both
mudrock-dominated and sandstone-dominated formations influence the
substrate as a result of folding, a karoo Hirpicium integrifolium (Haarbossie)
dominated shrubland where succulents are in abundance on the Dwyka tillite,
and a distinct Thamnochortus bachmannii restio-dominated sandveld in areas
where deep aeolian sand had accumulated.
The differences in vegetation communities are mainly based on geology with
consequent soil characters and degree of rockiness, as well as topography,
moisture availability and the water holding capacity of the soil. Although slope,
aspect and elevation can sometimes be associated with specific plant
communities, geology, soil pH and rock cover are the principal elements
responsible for shaping the vegetation mosaic. Rather than a broad ecotone,
the vegetation of the study area is understood as a complex mosaic mountain
vegetation entity.Environmental SciencesPh. D. (Environmental Sciences
