Included here are the deserts and semi-deserts of the Great Karoo (or Nama Karoo) east of the Western Cape in South Africa and lying at the centre of the South African plateau (or meseta). It also extends over the Orange River into Namibia in the northwest. The Great Escarpment, which runs parallel to the coast 100 km to 200 km inland, divides it into two parts: one between 550 m to 900 m in elevation, the other between 900 and 1300 m.

Noorsveld

Dominated by the endemic grey, shrubby, stem succulent Euphorbia coerulescens (Euphorbiaceae) this veld type can be found as a wide belt along the sinuous middle section of the Sundays River Valley north of Grootriver Heights and Suurberg and centered on Jamsenville but with outliers occurring on the lower slopes of Great Winterhoek Mountains. The vegetation is named after noors the local name for euphorbias. Other shrubs include Aloe ferox, Capparis oleoides, Carissa haematocarpa, Euclea undulata, Grewia robusta, Lycium austrinum, Maytenus capitata, M. polyacantha, Nymania capensis, Pappea capensis, Portulacaria afra, Rhigozum obovatum, Rhus undulata and Schotia afra, although apart from the dark green Capparis oleoides, Lycium austrinum, Pappea capensis and Schotia afra most of these shrubs are fairly inconspicuous. In the often-bare patches between the shrubs are scatterings of species such as Eragrostis obtusa, Eriocephalus ericoides, Euphorbia ferox, Indigo sessilifolia, Mestoklema tuberosum, Pentzia incana, Phymaspermum pubescens and Selago triquetra. However, this veld type is often badly affected by over grazing. Among the less common components is the local endemic Euphorbia jansenvillensis (Euphobiaceae).

Spekboomveld

Named after the dominant species, named locally as spekboom (Portulacaria afra), this veld type can be found on steep sandstone quartzite and shale mountain slopes in the east and south Cape. It forms a dense scrub, which includes various succulent species. Common trees and shrubs include Crassula portulacea, Euclea undulata, Grewia robusta, Lycium austrinum, Pappea capensis, Rhigozum obovatum, Rhus lucida, R. longispina, Schotia afra and Tarchonanthus minor. Typical small plants comprise a variety of Crassula species such as C. cultrata, C. lycopioides, C. obvallata, C. perfoliata, C. perforata, C. rogersii, C. rupestris, C. tetragona together with Adromischus poellnitzianus, Cotyledon orbiculata, C. ramosissima, Cyphia sylvatica, Delosperma frutescens, Euphorbia mauritanica, Panicum maximum, Sansevieria thyrsiflora and Senecio junceus.

Bloomkoolganna Veld (Arid Karoo)

This veld type, named after bloomkoolganna the local name for the dominant and also poisonous Salsola tuberculata, is thought to be the climax vegetation of the Arid Karoo. This is the driest part of South Africa with rainfall ranging from just 50-200 mm a year. Most of the Arid Karoo is at an altitude of 900 m but the terrain is extremely flat except along the northern zone of the Roggeveld Mountains where it forms an undulating landscape across the valley of the Sak River. Along the edge of the Orange River it drops to an altitude of about 450 m. Bloomkoolganna Veld is best developed on sandy calcareous tufa mainly found on the northeast and northern borders of the Arid Karoo. It forms a fairly dense growth dominated by Salsola tuberculata and the grasses Stipagrostis ciliata and S. obtusa. Despite the dryness ground cover is surprisingly well developed with short grasses such as Enneapogon desvauxii, Eragrostis nindensis, Ovopetium capensis, Sporobolus lampranthus and Stipagrostis brevifolia predominating. The latter species is said to be the hardiest of all Arid Karoo plants – in severe draught it sheds its leaves and curls up into a yellow-brown ball and can survive when all other plants succumb. Annuals and geophytes are fairly abundant but not very conspicuous. Among the geophytes is the fern Ophiglosssum polyphyllum. Other typical species are Aptosimum spinescens, Dicoma capensis, Eriocephalus spinosus, Hermania spinosa, Lycium oxycladum, Nestleria humilis, Pentzia spinescens, Pteronia glomerata, Rhigozum trichotomum, Ruschia ferox, Salsola glabresens, Sarcocaulon patersonii and Zygophyllum microphyllum. Species of less general occurrence include Acanthopsis hoffmanseggiana, Aizoon schellenbergii, Aptosimum steingroeveri, Berkheya annectens, Geigeria ornativa, Limeum aethiopicum, Lycium arenicolum, Monechma desertorum, Osteospermum armatum, Peliostomum leucorrhizum, Pentzia pinnatisecta, Phaeoptilum spinosum, Plinthus karrooicus, Polygala seminuda, Pteronia leucoclada, Selago minutissima, Tribulus terrestris, Zygophyllum gilfillani and so on. Much of the veld type known as Central Upper Karoo (see below) has now been invaded by Arid Karoo elements due to disturbance from excessive grazing and in places this is now little different from Arid Karoo, and therefore known as False Arid Karoo. 

Central Lower Karoo

This veld type has affinities with Arid Karoo, but situated at lower altitudes (700-1050 m) is not quite as arid. It occupies flat, stony terrain partly on calcareous tufa and partly on stony sandstone and shale. It tends to be shorter and denser than Arid Karoo sometimes having almost complete ground cover. Eberlanzia vulnerans, Pentzia incana and other succulents play an important role, while typical grasses include Stipagrostis ciliata and S. obtusa, both of which are characteristic of Arid Karoo. Other typical species include Aptosimum steingroeveri, Asaemia axillaris, Drosanthemum framesii, Eriocephalus spinescens, Felicia filifolia, Hermannia cuneifolia, Justicia orchioides, Lycium prunus-spinosa, Nestlera conferta, Osteospermum spinescens, Phymaspermum pubescens, Ruschia uncinella, Sphalmanthus tetragonu and Zygophyllum incrustatum. In this dense vegetation very few annuals occur but species of Galenia may be present.

Orange River Broken Veld

This veld type can be divided into three sub-types. The more typical type is characterized by Aloe dichotoma and Euphorbia avasmontana. It occurs on steep rocky mountains between Prieska and Kakamas. The second type, largely dominated by Rhigozum trichotomum, occurs on gravel and stony plains; while the third type is predominantly Acacia mellifera subsp. detinens extends up the valleys of the Vaal-Hartz and Orange River valleys. However, only the typical veld type will be described here. It occurs on various rock types including banded ironstone, dolomite, quartzite and granite at altitudes ranging from 750-1350 m. Other typical trees and shrubs include Acacia mellifera, A. karoo, Boscia albitrunca, Lycium austrinum, Ehretia rigida, Phaeoptilum spinosum, Rhigozum trichotomum, R. obovatum, Sarcostemma viminale and Ziziphus mucronata. Among the many smaller plants are Aizoon burchelii, Barleria tigida, Corbichonia decumbens, Dicoma capensis, Euryops multifidus, Felicia muricata, Garuleum schinzii, Helichrysum lucilioides, Indigofera sessilifolia, Lasiocorys capensis, Osteospermum microphyllum, Pachypodium succulentum, Rogeria longiflora, Senecio longiflorus, Talinum caffrum and Zygophyllum suffrutocosum.

Karroid Broken Veld

Characteristic of very arid, stony places virtually devoid of soil this veld type includes a variety of stunted shrubs, and to make matters worse these areas experience the phenomenon known as ‘dry rain’ (wisps of precipitation evaporating before reaching the ground). The principal shrubs include Chrysocoma tenuifolia, Delosperma subincanum, Dicoma spinosa, Drosanthemum framesii, Eriocephalus spinescens, Euphorbia arida, Felicia filifolia, Galenia fruticosa, Garuleum bipinnatum, Helichrysum lucilioides, Hermannia cuneifolia, Lasiosiphon meisnerianus, Lebeckia spinescens, Limeum aethiopicum, Microloma massonii, Monechma pseudopatulum, Osteospermum sinuatum, Pentzia spinnescens, Polygala seminuda, Pteronia adenocarpa, Salsola rabieana, Sarcocaulon patersonii, Sericocoma avolans, Tetragonia fruticosa, Trianthema triquetra, Trichodiadema barbatum and Zygophyllum microphyllum.  Some of the principal grasses are Aristida diffusa, Cenchrus ciliaris, Digitaria argyrograpta Enneapogon scaber, Eragrostis obtusa, Fingerhuthia africana, Heteropogon contortus, Oropetium capense, Sporobolus fimbriatus, Stipagrostis obtusa, Themeda triandra and Tragus koelerioides.

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