The vegetation of the Kalahari Gemsbok National Park, which lies in the centre of the semi-arid Southern Kalahari, was studied. This area is considered to be largely representative of the Southern Kalahari in general. The region is covered by a layer of red sand piled into dunes. Two large dry river-beds cross the area and numerous pans occur. Calcrete outcrops are found along rivercourses and around pans. The vegetation is generally an extremely open shrub or tree savanna and phytogeographically the area is regarded as belonging to the Karoo-Namib Region.