Robertson Karoo low hills and flats covered in small succulent vegetation, usually growing on rocky shale-based soils. The climate is semi-arid due to the region lying in the rainshadow of the large mountain ranges to the south-west, but the rainfall does tend to occur mainly in winter. This vegetation type has a large number of endemic species and several endemic genera. Robertson Karoo Robertson Karoo is a semi-arid vegetation type, restricted to sections of the Breede River Valley, Western Cape Province, South Africa. It is a subtype of Succulent Karoo (geographically an extension of the "Little Karoo") and is characterised by the
Karoo Supergroup of basaltic lava over the Clarens desert, covering nearly the whole of Southern Africa and other portions of Gondwana.The pile of lava that accumulated over the course of several eruptions was more than 1600 m thick, especially in the east (in present-day Lesotho). This massive lava outpouring brought the Karoo sedimention to an abrupt end. The name Drakensberg group is derived from the fact that this layer forms the uppermost 1400 m of the Great Escarpment on the international border between Lesotho and KwaZulu-Natal, often referred to as "the" Drakensberg (although technically the "Drakensberg" refers to the entire 1000 km