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Census of the Vegetation Present
At Wild at Tuli, Central Tuli Block,
Botswana
The central Tuli Block is a relatively understudied and isolated area in terms of scientific research. Its landscape and climate closely resembles that to be found on the South side of the Limpopo River, which it abuts, but has experienced very little of the scientific research that has been conducted on the South African side of the border. For this reason we felt it was necessary to perform a census of the vegetation in the area simply to get a better understanding of the diversity of plants and what this would mean for the mammal and bird species which are and could be found in the area. Plants are the base unit for most ecosystems on land and as such it is essential to know which plant species are in an area which is being conserved so you can better understand the reasons for animal distributions, populations and fluctuations as well as knowing whether or not prospective reintroductions of previously extinct species would be successful in the area or areas similar to it. Area: The census was conducted on the game farm Mothomololo, where Wild at Tuli Safaris is
situated, the area will hereafter by referred to as Wild at Tuli. Wild at Tuli is a 5000 hectare property
with approximate dimensions of approximately 20km by 4 to 0.6km. The property runs along the
Limpopo River in the South-East and borders one of Botswana's many veterinary fences to the North-
West. The area falls within the broad label of southern African savannah biome. The landscape is
unique to Botswana and is characterised by large numbers of granite outcrops, colloquially referred to
as ‘Kopjes'. The farm is therefore made of 3 distinct vegetation types as a result of the 3 very different
habitats found there. The first of these is riverine, which is found in a thin strip, no more than 400m
wide, along the banks of the Limpopo and on its islands, secondly, kopje vegetation which is found
growing on the rocky outcrops. The final type is referred to as Mopane Woodland due to the
overwhelming presence of Mopane (Colophospermum mopane) and is found across most of the flat
land away from the river. Due to variability in access to the 3 types of vegetation, different methods
were used to sample and record the vegetation that was found in these areas.
Vegetation and Substrate Survey Method:
Mopane Woodland and Riverine: Vegetation was sampled in these two habitats in the same manner. Transects of varying length were conducted at random across the property and then recorded on Google Earth to ensure all areas of the property were sampled. These transects were then walked by 2 samplers. The first carried a pole 1m in length at waist height with half the pole protruding from each side of the sampler's hands. They then walked in as straight a line as could be managed depending on the terrain in a direction determined by the area which needed to be sampled. Every woody plant that was touched by the pole was recorded by the second sampler. Effort was made to ensure game paths and other natural features were not followed which may have confounded results and also to keep the pole at the same level throughout each sampling session. Trees which passed below the pole were not recorded as they were deemed too young to be properly established. A transect was complete when 100 samples had been collected. Transect lengths varied from 400m to 2.5km depending on the density of vegetation in the area. The substrate was recorded in the Mopane woodland and riverine by placing a pole on the ground approximately every 2m and recording what type of substrate was hit. The transects followed the same paths as the vegetation census. The study recognised 7 different substrate types: rock, soil, organic matter, non-woody vegetation, termite mounds, river sand and artificial surfaces. If immature woody vegetation was struck then this was also recorded as a separate type. Organic matter was defined as anything which was no-longer living but was derived from biotic origins and had not completely decomposed into soil, i.e. leaf litter, animal dung and bones. Non-woody vegetation was defined as all grasses, sedges and low growing soft stemmed flowering plants. Two samplers were used each time to record the samples and 200 samples were collected for each transect. Kopje: Due to problems accessing large area of the kopjes for effective sampling no repeatable
surveys were conducted in the same manner as for Mopane Woodland and Riverine. Instead basic
collation of tree species was recorded with observed relative abundances. No substrate survey was
conducted as it was evident that the most common substrate type was rock and all soil or organic
matter in which plants were growing was largely isolated in cracks in the rocks surface.
Small Plants: Small plants were sampled by walking in the bush in various habitat types, collecting
and identifying them for the general purpose of better understanding the diversity of plants in the area.
Again, no formal survey of small flowering plants was conducted as this time.
NB: Several Grewia species, commonly called Raisin Bush, were observed but due to
identification difficulties during winter and their tendency to interbreed they are treated here
as a single entity.
General Results: Over the course of the study 6300 samples of woody vegetation and
12400 substrate samples were collected across the 2 vegetation types that were sampled in
the same manner. 48 species of tree were recorded across the property (appendix 1). 35
species of tree were recorded during the survey of Mopane woodland and riverine of which
only 6 species accounted for more than 1% and those 6 species accounted for a total of
98.27% of all species recorded on the property. By far the most abundant was Mopane with
60.60% of the sample (Figures 1). Figure 2 shows the proportions of the remaining 1.3% of
species which were recorded fewer than 10 times. In the substrate survey soil was the most
abundant substrate type accounting for 58.22%, followed by organic matter at 17.84% and
non-woody vegetation at 14.10% (Figure 3).
Figure 1. Major (>10 recorded) Vegetation Species at Wild at Tuli between Oct 2012
and Der 2013
Shepherd's Tree Weeping Boer Bean Tamboti Apple Leaf Large Feverberry Forest False-Nettle Lowveld Clusterleaf Figure 2. Minor (<10 recorded) Vegetation Species at Wild at Tuli between Oct 2012
and Dec 2013
Savanna Gardenia Wild Date Palm Flame Thorn Short-thorn Common Spike Thorn Sandpaper Raisin Figure 3. Overall Substrate Types at Wild at Tuli between Oct 2012 and Dec 2013
Woody Vegetation Artificial Surfaces Riverine: Riverine areas were dominated by a low level layer of Forest False-Nettle (Acalypha
glabrata) interspersed with larger trees. Forest False-Nettle accounted for 50.83% of 600 samples in
the riverine. A total of 25 species were recorded in the riverine vegetation areas, with Large
Feverberry (Croton megalabotrys) (11.12%) and Raisin Bush (Grewia spp.) (11%) being the second
and third most abundant species (Figures 4). Figure 5 shows the composition of the other 4% of
species recorded on less than 5 occasions. Riverine substrate surveys showed soil (64.2%) and
organic matter (28.4%) to be most abundant totalling 92.6% collectively (Figure 6).
Figure 4. Major (>5 records) Riverine Species recorded at Wild at Tuli between Oct
2012 and Sep 2013
Knobbly Combretum Weeping Boer Bean Forest False-Nettle Large Feverberry Figure 5. Minor (<5 records) Riverine Species recorded at Wild at Tuli between Oct
2012 and Sep 2013
Savanna Gardenia Sandpaper Raisin Lowveld Clusterleaf Figure 6. Riverine Substrate Types at Wild at Tuli between Oct 2012 and Sep 2013
Artificial Surfaces Woody Vegetation Mopane Woodland: The Mopane woodland showed a much lower diversity than the riverine. At total
of 5700 vegetation samples were taken. Only 6 species were recorded on more than 10 occasions
out of a total of 24 recorded species. Those species were Mopane (65.11%), Lowveld Cluster-leaf
(Terminalia prunoides) (15.56%), Red Bushwillow (Combretum apiculatum) (9.89%), Grewia spp.
(7.81%), Shepherd's Tree (Boscia spp.) (0.56%) and Umbrella Thorn (Acacia tortilis) (0.16%) (Figure
7). Figure 8 indicates the composition of the remaining 18 species and 0.89%. The substrate in the
Mopane woodland showed soil again to be most abundant (57.69%) but organic matter, non-woody
vegetation and rock were much more prominent accounting for 16.91%, 15.08% and 7.89%
respectively (Figure 9).
Figure 7. Mopane Woodland Major (>10 records) Species recorded at Wild at Tuli
between Oct 2012 and Sep 2013
Shepherd's Tree Umbrella Thorn Lowveld Clusterleaf Figure 8. Mopane Woodland Minor (<10 records) Species recorded at Wild at Tuli
between Oct 2012 and Sep 2013
Common Spike Thorn Knob Thorn Baobab Knobbly Combretum White Berry Bush Figure 9. Mopane Woodland Substrate Survey
Woody Vegetation Artificial Surfaces Kopje: No substrate survey was conducted for the kopjes, however it can be assumed that >80% of
the viewable surface substrate on the kopjes was bare rock; the remaining 20% would likely consist
solely of organic matter, soil and non-woody vegetation. 21 species of tree were recorded on the
kopjes. The diversity of species differed between the kopjes in the northern part of the property and
those in the south. White Seringa (Kirkia acuminate) and Stunted Plane (Ochna inermis) were most
visibly more abundant in the south whereas Carrot Trees (Steganotaenia araliacea) were virtually
non-existent in the south but were regularly observed in the north. Grewia spp. was common on
kopjes throughout the property. Most kopjes also had small clusters of both Marula (Sclerocarya
birrea) and Euphorbia spp.
Small Plants: No abundance or distribution data was collected with regards to small flowering plants.
However, a basic inventory of species was created and a total of 125 non-tree flowering species were
recorded (appendix 2).
The data shows that Mopane is overwhelmingly the most abundant tree species at Wild at Tuli. The species dominates the flat open country away from the Limpopo River. Grewia spp, Lowveld Terminalia and Red Bushwillow form isolated strands amongst the expanse of Mopane. The riverine areas are densely populated with trees but are very limited in terms of area. The medium height undergrowth is dominated by Forest False-Nettle which is not immediately obvious as the large trees appear more striking at first glance but are in fact relatively widely dispersed across the area. Weeping Boer Beans (Schotia brachypetala), Tamboti (Spirostachys africana) and Apple Leaf (Philenoptera violacea) were the most common large trees in the riverine but represented only 11% of riverine vegetation and less than 3% of the overall abundance of tree species on the property. The reason for this diversity and distribution of species is most likely linked to the abundance of water. For example several riverine species such as Apple Leaf and Leadwood (Combretum imberbe) were found occasionally in the mopane woodland. They were usually located along drainage lines which had sufficient year round ground water. The area as a whole is very dry, experiencing less than 300mm of rain annually. This means that only hardy species such as Mopane can survive away from permanent water or ground water sources. Mopane also produces chemicals known as secondary metabolites which it secretes into the soil from its roots. These chemicals inhibit the growth of other species allowing Mopane to take over large areas. The species found on kopjes are even hardier than those found on the flat ground as they are much further from water sources and so often are quite soft woods which are capable of holding large amounts of water such as Corkwoods (Commiphora spp.) or Baobab (Adansonia digitata) or succulents like Euphorbia's. The composition of tree species which was discovered is important for understanding why certain species are present and others are not. For example the very low population of Giraffe in the area is most likely linked to the almost total lack of suitable browse trees for them in the form of Acacia species. As the land is dominated by Mopane, only species which are able to feed on Mopane with its high tannin levels are able to survive. This relates to all levels of the animal kingdom from invertebrates to mammals and birds. Only certain species of insect can tolerate Mopanes tannin levels and therefore the species which feed on insects are limited to those which feed on those unique species which can survive feeding almost entirely on Mopane. The substrate survey tells us that the ground in the Mopane woodland is largely soil which in itself is good as it provides ample locations for new plants to sprout. However when compared to the riverine substrate survey it becomes clear that there is a dramatic shortage of organic matter at the surface and it contains more nutrients than silica or clay based soils which are present across the property. More organic matter on the surface of the land is important as it acts as an immediate energy and nutrient source for new growth as well as a protective layer for new shoots from wind, excessive sun exposure, water and animals. Without this layer seeds from plants are easily blown or washed away or eaten by birds or other animals before they have a chance to root. This is evidenced in the kopjes where plants are only able to grow in the protected crevices of the rocks and very few species are able to germinate and send out shoots on the bare rock surfaces. One surprising discovery of this study has been the high diversity of smaller flowering plants. Despite the landscape appearing to consist of only 3 major components, within these areas there is a large variation of micro-climates allowing this large diversity to have developed and survived. Much further study is required in this area as no demographic data was collected and several recorded species are protected in South Africa due to their scarcity there, e.g. Kwebe Hills Stapelia (Stapelia kwebensis). This study also highlighted the number of alien species which exist in the area, a total of 10 alien species were recorded and efforts must be made to study the impacts they are having on the environment and if necessary removal of these species should take place. Table 1. List of Tree Species observed at Mothomololo Farm, Botswana between
October 2012 and December 2013 .
ENGLISH NAME
SCIENTIFIC NAME
Family ANACARDIACEAE
Sclerocarya birrea
Family APIACEAE
Carrot Tree
Steganotaenia araliacea
Family ARECACEAE
Wild Date Palm
Phoenix reclinata
Lala Palm
Hyphaene coricea
Family ASTERACEAE
Wild Camphor Bush
Tarchonanthus camphoratus
Family BIGNONIACEAE
Trumpet Thorn
Catophractes alexandri
Bell Bean Tree
Markhamia zanzibarica
Short-Thorn Pomegranate
Rhigozum brevispinosum
Family BOMBACACEAE
Adansonia digitata
Family BURSERACEAE
Tall Common Corkwood
Commiphora glandulosa
Zebra-bark Corkwood
Commiphora merkei
Common Corkwood
Commiphora pyracathoides
Family BORAGINACEA
Sandpaper Bush
Ehretia amoena
Family CACTACEAE
Sweet Prickly Pear*
Optunia ficus-indica
Family CAESALPINIACEAE
Sjambok Pod
Cassia abbreviata
Colophospermum mopane
Weeping Boer-bean
Schotia brachypetala
Family CAPPARACEAE
Shepherd's Tree
Boscia albitrunca
Stink Shepherd's Tree
Boscia foetida subsp.
Family CELASTRACEAE
Transvaal Saffron
Cassine transvaalensis
Red Spike-thorn
Gymnosporia senegalensis
Family COMBRETACEAE
Lowveld Clusterleaf
Terminalia prunoides
Red Bushwillow
Combretum apiculatum
Russet Bushwillow
Combretum hereonse
Leadwood
Combretum imberbe
Knobbly Creeper
Combretum mossambicense
Family EUPHORBIACEAE
Forest False Nettle
Acalypha glabrata
Transvaal Candelabra
Euphorbia cooperi
Rubber Euphorbia
Euphorbia tirucalli
Common Tree Euphorbia
Euphorbia ingens
White-berry Bush
Flueggea virosa
Spirostachys africana
Large Feverberry
Croton megalobotrys
Family FABACEAE
Nyala Tree
Xanthoceris zambesiaca
Apple Leaf
Philenoptera violacea
Family MENISPERMACEAE
Python Climber
Cocculus hirsutus
Family MIMOSACEAE
Knob Thorn
Acacia nigrescens
Umbrella Thorn
Acacia tortilis
Sickle Bush
Dichrostachys cinerea
Family MORACEAE
Large-leaved Rock Fig
Ficus abutilifolia
Common Cluster Fig
Ficus sycamores
Small-leaved Rock Fig
Ficus tettensis
Family OCHNACEAE
Stunted Plane
Ochna inermis
Family PEDALIACEA
Transvaal Sesame-bush
Sesamothamnus lugardii
Family RHAMNACEAE
Brown Ivory
Berchemia discolor
Buffalo Thorn
Ziziphus mucronata
Family RUBIACEAE
Savanna Gardenia
Gardenia volkensii
Green Tree
Psydrax livida
Family SALVADORACEAE
Mustard Tree
Salvadora persica
Family SAPINDACEAE
Jacket-Plum
Pappea capensis
Family SIMAROUBACEAE
White Seringa
Kirkia acuminata
Family STERCULIACEAE
Common Star-Chestnut
Sterculia rogersii
Family TILIACEAE
White Raisin
Grewia bicolor
Velvet Raisin
Grewia flava
Sandpaper Raisin
Grewia flavescens
Mallow Raisin
Grewia villosa
PRESENCE TO BE CONFIRMED
Flame Thorn
Acacia ataxacantha
Table 2. List of Flower Species observed at Mothomololo Farm, Botswana between
October 2012 and December 2013, (*) indicate alien species
ENGLISH/AFRIKAANS NAME
SCIENTIFIC NAME
Family ACANTHACEAE (Acanthus Family)
Limpopo Barleria
Barleria transvaalensis
Eyelash Flower
Blepharis subvolubilis subsp. subvolubilis
Yellow Justicia
Justicia flava
4.
No common name
Justicia protracta subsp. protracta
Veld Justicia
Justicia protracta subsp. rhodesiana
Blue Cloak
Megalochlamys revolute subsp. cognata
Neuracanthus africanus
Petalidium aromaticum var. canescens
Veld Violet
Ruellia cordata
10. White Veld Violet
Ruellia patula
Family AMARANTHACEAE (Amaranth Family)
11. Bachelor's Button*
Gomphrena celoioides
12. Katstart
Hermbstaedia fleckii
13. Cat's Tail
Hermbstaedia odorata var. albi-rosea
14. Silky Burweed
Kyphocarpa angustifolia
15. Silwerbossie
Leucosphaera bainesii
Family AMARYLLIDACEAE (Amaryllis Family)
16. Tiny Crinum
Crinum walteri
17. Vlei Lily
Nerine laticoma
18. Aandblommetjie
Pancratium tenuifolium
Family APOCYNACEAE (Oleander Family)
19. Giant Milkweed*
Calotropis procera
20. Cotton Milkweed
Gomphocarpus fruticosus subsp. decipiens
21. Ghaap
Hoodia currorii subsp. lugardii
22. Kwebe Hills Stapelia
Stapelia kwebensis
Family ASPARAGACEAE (Asparagus Family)
23. Bushveld Asparagus
Asparagus suaveolens
Family ASTERACEAE (Daisy Family)
24. Wing-stemmed Daisy
Calostephore divaricate
25. Hairy Dicoma
Dicoma tomentosa
26. Vlei Pompom
Doellia cafra
27. Smelter's Bush*
Flaveria bidentis
28. Rosulate Geigeria
Geigeria acaulis
29. Knoppiesvermeerbos
Geigeria burkei burkei
30. Wild Everlasting
Helichrysum argyrosphaerum
31. Dwarf Sage
Litogyne gariepina
32. Stinkbush/Wild Sage
Pechuel-Loeschea leubnitziae
33. Sticky Psiadia
Psiadia punctulata
34. Wild Sunflower*
Verbesina encelioides var. encelioides
35. Narrow-leaved Vernonia
Vernonia fastigiata
Family BORAGINACEAE (Forget-me-not Family)
36. Kalahari String of Stars
Heliotropium ciliatum
37. Narrow-leaved Heliotropium
Heliotropium lineare
38. Riverbank Heliotropium
Heliotropium ovalifolium
Family BYTTNERIACEAE (Chocolate Family)
39. Groot Gembossie
Hermannia boraginiflora
40. Fairy Lights
Hermannia modesta
41. Meidebossie
Waltheria indica
Family CAPPARACEAE (Caper Family)
42. Yellow Mouse-whiskers
Cleome angustifolia subsp. petersiana
43. Single-leaved Cleome
Cleome monophylla
Family COMMELINACEAE (Commelina Family)
44. Benghal Blue Wandering Jew
Commelina benghalensis
Family CONVOLVULACEAE (Morning Glory Family)
45. Blue Haze
Evolvulus alsinoides
46. Leaf-flowered Ipomoea
Ipomoea crassipes
47. Prickly Stem Merremia
Merremia kentrocaulos
48. Small White Seddera
Seddera capensis
Family CUCURBITACEAE (Pumpkin, Cucumber or Gourd Family)
49. Wild Cucumber
Cucumis anguira var. longaculeatus
Family CYPERACEAE (Sedge Family)
50. Russet Rock Sedge
Cyperus rupestris
51. White Button Sedge
Kyllinga alba
52. Golden Sedge
Pycreus pelophilus
53. Spring Onion Sedge
Schoenoplectus senegalensis
Family ERIOSPERMACEAE (Eriospermum Family)
54. Small Fluffy Seed
Eriospermum porphyrovalve
Family EUPHORBIACEAE (Rubber Family)
55. Indian Girl*
Acalypha indica var. indica
56. Dolomite Euphorbia
Euphorbia griseola subsp. griseola
57. Limpopo Euphorbia
Euphorbia limpopoana
58. Klein Bont Euphorbia
Euphorbia neopolycnemoides
59. Rocky Jatropha
Jatropha spicata
Family FABACEAE (Pea Family)
60. Hairy Pod Cassia
Chamaecrista absus
61. Narrow-Leaved Rattle Pod
Crotalaria heidmannii
62. Mealie Crotalaria
Crotalaria sphaerocarpa subsp. sphaerocarpa
63. Hairy Indigo
Indigofera heterotricha
64. Creeping Indigo
Indigofera holubii
65. No common name
Indigofera schimperi var. schimperi
66. Grassy False Indigo
Microcharis galpinii
67. Bushveld Pig's Tail
Ptycholobium contortum
68. Spiny Sesbania*
Sesbania bispinosa var. bispinosa
69. No common name
Tephrosia kraussiana
70. Silver Tephrosia
Tephrosia purpurea
71. No common name
Tephrosia semiglabra
Family GERANIACEAE (Geranium Family)
72. Dysentry Herb
Monsonia glauca
73. Pienk angelbossie
Monsonia senegalensis
Family GISEKIACEAE (Gisekia Family)
74. Rooi-rankopslag
Gisekia africana var. africana
Family HYACINTHACEAE (Hyacinth Family)
75. Waxy Albuca
Albuca glauca
76. Poison Onion
Dipcadi glaucum
77. Groenlelie
Dipcadi papillatum
78. Mopane Veld Dipcadi
Dipcadi vaginatum
79. No common name
Ledebouria luteola
80. No common name
Ledebouria marginata
81. No common name
Ledebouria spp.
82. Bushveld Chincherinchee
Ornithogalum seineri
Family LAMIACEAE (Sage Family)
83. Tinderwood
Clerodendrum ternatum
84. Mopane Veld Keepsakes
Endostemon tenuiflorus
85. Small Purple Keepsakes
Endostemon tereticaulis
86. Annual Wild Dagga
Leonotis nepetifolia var. nepetifolia
87. Dainty Tumbleweed
Leucas glabrata var. glabrata
88. Bushveld Tumbleweed
Leucas sexdentata
89. Wild Basil
Ocimum americanum var. americanum
Family LIMEACEAE (Limeum Family)
90. Lintblommetjie
Limeum fenestatum
91. Klossarbossie
Limeum sulcatum var. sulcatum
Family LYTHRACEAE (Pride of India Family)
92. Sandsloot-nesaea
Nesaea schinzii
Family MALVACEAE (Cotton Family)
93. Wild Abutilon
Abutilon pycnodon
94. No common name
Abutilon rehmannii
95. Bushveld False Hibiscus
Cienfuegosia digitata
96. Wild Hibiscus
Hibiscus engleri
97. Tiny White Wild Hibiscus
Hibiscus micranthus var. micranthus
98. Pale Yellow Hibiscus
Hibiscus palmatus
99. No common name
Hibiscus sidiformis
Family MOLLUGINACEAE (Mollugo family)
100. Sierkooltjie
Corblchonia decumibens
101. White Star Mollugo*
Mollugo nudicaulis
Family NYCTAGINACEAE (Four-o'clock Family)
102. No common name
Boerhana coccinea var. coccinea
Family OLEACEAE (Olive and Jasmine Family)
103. Wild Jasmine
Jasminum sp.
Family PEDALIACEAE (Sesame Family)
104. Wild Foxglove
Ceratotheca triloba
105. Sac Flower
Holubia saccata
106. Wing-seeded Sesame
Sesame alatum
Family PORTULACACEAE (Purslane Family)
107. No common name
Portulaca cf. collina
Family SAPINDACEAE (Litchi or Soapberry Family)
108. Bushveld Ballon Vine
Cardiospermum corindum
Family SCROPHULARIACEAE (Snapdragon Family)
109. Carpet Flower
Aptosimum lineare
110. Blue Carpet
Craterostigma plantagineum
111. Vlei Snapdragon
Diclis petiolaris
Family SOLANACEAE (Potato Family)
112. Large Thorn-Apple*
Datura ferox
113. Hairy Thorn-Apple*
Datura inoxia
114. Bitterappel
Solanum delegoense
Family SPARRMANNIACEAE (Jute Family)
115. Geel Varingblaartjie
Corcherus asplendifolius
Family TURNERACEAE (Wormskioldia Family)
116. Haarbossie
Piriqueta capensis
117. Yellow Lion's Eye
Triciliceras glanduliferum
Family VAHLIACEAE (Vahlia Family)
118. Toiingbossie
Vahlia capensis subsp. vulgaris var. vulgaris
Family VELLOZICEAE (Vellozia Family)
119. Reënmeterjies
Xerophyta humilis
120. Black-stick Lily/Baboons Tail
Xerophyta retinervis
Family VERBENACEAE (Verbena Family)
121. Bird's Brandy
Lantana rugosa
Family VIOLACEAE (Violet Family)
122. Pink Lady's Slipper
Hybanthus enneaspermus var. serratus
Family VITACEAE (Vine or Grape Family)
123. Bobbejaandruif/we
Cyphostemma sandsonii
Family ZYGOPHYLLACEAE (Caltrop Family)
124. Devil's Thorn
Tribulus terrestris

Source: http://www.projects-abroad.fi/_downloads/uk/conservation-management-plan/data-and-reports/south-africa/vegetation-survey.pdf