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Background: The Great Escarpment of southern Africa takes the form of an extended mountainous highland in central-western Namibia, commonly referred to as the ‘Khomas Hochland’. It is regarded as an area of high botanical diversity. Yet only few localised studies on the vegetation composition are available. The Khomas Hochland is formed on the southern part of the Damara Orogen and dominated by metamorphosed sediments. Climatically it forms a transition between the hot desert of the Namib and the slightly cooler hot steppe in the inland.Objectives: To classify and provide syntaxonomical descriptions of the vegetation of the Khomas Hochland.Methods: A dataset comprising 1151 relevés and 914 species was compiled from various surveys, mostly collected under, and to the standards of, the umbrella project ‘Vegetation Survey of Namibia’. For first classifications, the data set was reduced to a synusial set consisting of trees, shrubs, dwarf shrubs and grasses only.Results: The classification resulted in four major landscape units, being the Pre-Namib and Escarpment zone, the Khomas Hochland proper, riverine habitats as well as surrounding lowlands. The classification was further refined using Cocktail procedures to produce 30 associations, one with four sub-associations. These are described in this paper.Conclusion: A classification of synoptic data grouped the associations into five orders and one undefined cluster of associations on specialised desert habitats. Four of these orders correspond to the habitat types identified in the first classification. The fifth order, the Senegalio hereroensis–Tarchonanthoetalia camphorathi, represents high mountains of the central Khomas Hochland, which link biogeographically to the grassland biome in South Africa.

Limited historic vegetation data (prior to the 1980s) are available for Namibia. Finding such historic data at Haribes prompted a follow-up survey of the vegetation. We present a classification of the recent data in this paper as a first step towards comparing the two data sets. Six new associations (three with two subassociations each) are formally described. The landscape at Haribes is dominated by a pan with surrounding hummock dunes. The pan supports the Lycio cinereum – Salsoletum, whilst on the hummock dunes the Salsolo – Tetragonietum schenckii can be found. The surrounding plains and escarpment can be divided into three landforms: the torras with the Monsonio umbellatae – Boscietum foetidae, the ranteveld with the Acacio senegal – Catophractetum alexandri (and two subassociations) and calcrete ridges with the Zygophylo pubescentis – Leucosphaeretum bainesii. Dry river beds on the farm support two subassociations of Anthephoro pubescentis – Ziziphodetum mucronatae. The area covered by each dominant landform has been calculated after being mapped. The composition and diversity of the associations are briefly compared to other known vegetation descriptions within the Nama-Karoo. Since November 2011, Haribes has been used as a resettlement farm. This may result in the overutilisation of the limited grazing resources, to the extent that the present, fairly dense Acacio senegal – Catophractetum alexandri of the ranteveld is feared to become degraded to resemble the Monsonio umbellatae – Boscietum foetidae of the torras.Conservation implications: This paper describes six plant associations of the Nama-Karoo biome in arid southern Namibia. The information presented forms a baseline description, which can be used for future monitoring of the vegetation under altered land use.

Limited historic vegetation data (prior to the 1980s) are available for Namibia. Finding such historic data at Haribes prompted a follow-up survey of the vegetation. We present a classification of the recent data in this paper as a first step towards comparing the two data sets. Six new associations (three with two subassociations each) are formally described. The landscape at Haribes is dominated by a pan with surrounding hummock dunes. The pan supports the Lycio cinereum – Salsoletum, whilst on the hummock dunes the Salsolo – Tetragonietum schenckii can be found. The surrounding plains and escarpment can be divided into three landforms: the torras with the Monsonio umbellatae – Boscietum foetidae, the ranteveld with the Acacio senegal – Catophractetum alexandri (and two subassociations) and calcrete ridges with the Zygophylo pubescentis – Leucosphaeretum bainesii. Dry river beds on the farm support two subassociations of Anthephoro pubescentis – Ziziphodetum mucronatae. The area covered by each dominant landform has been calculated after being mapped. The composition and diversity of the associations are briefly compared to other known vegetation descriptions within the Nama-Karoo. Since November 2011, Haribes has been used as a resettlement farm. This may result in the overutilisation of the limited grazing resources, to the extent that the present, fairly dense Acacio senegal – Catophractetum alexandri of the ranteveld is feared to become degraded to resemble the Monsonio umbellatae – Boscietum foetidae of the torras.Conservation implications: This paper describes six plant associations of the Nama-Karoo biome in arid southern Namibia. The information presented forms a baseline description, which can be used for future monitoring of the vegetation under altered land use.

Limited historic vegetation data (prior to the 1980s) are available for Namibia. Finding such historic data at Haribes prompted a follow-up survey of the vegetation. We present a classification of the recent data in this paper as a first step towards comparing the two data sets. Six new associations (three with two subassociations each) are formally described. The landscape at Haribes is dominated by a pan with surrounding hummock dunes. The pan supports the Lycio cinereum – Salsoletum , whilst on the hummock dunes the Salsolo – Tetragonietum schenckii can be found. The surrounding plains and escarpment can be divided into three landforms: the torras with the Monsonio umbellatae – Boscietum foetidae , the ranteveld with the Acacio senegal – Catophractetum alexandri (and two subassociations) and calcrete ridges with the Zygophylo pubescentis – Leucosphaeretum bainesii . Dry river beds on the farm support two subassociations of Anthephoro pubescentis – Ziziphodetum mucronatae . The area covered by each dominant landform has been calculated after being mapped. The composition and diversity of the associations are briefly compared to other known vegetation descriptions within the Nama-Karoo. Since November 2011, Haribes has been used as a resettlement farm. This may result in the overutilisation of the limited grazing resources, to the extent that the present, fairly dense Acacio senegal – Catophractetum alexandri of the ranteveld is feared to become degraded to resemble the Monsonio umbellatae – Boscietum foetidae of the torras . Conservation implications : This paper describes six plant associations of the Nama-Karoo biome in arid southern Namibia. The information presented forms a baseline description, which can be used for future monitoring of the vegetation under altered land use.