IN THE LAND OF THE BARRIER OF SPEARS

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IN THE LAND OF THE BARRIER OF SPEARS

• The Drakensberg Mountains of South Africa and
  Lesotho
• John and Hilary Birks

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The Barrier of Spears
Introduction Names Location Geology and
topography Climate Land-use and
fire Vegetation Botanical Features State of
knowledge Richness Endemics Altitudinal
Zonation Montane belt Subalpine belt Alpine
belt The Big Taxonomic Headache
Helichrysum! Why so Rich? Conservation and the
Future
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INTRODUCTIONNames
Barrier of Spears or 'a row of spears pointing
upwards' Zulu name (Quathlamba or uKhahlamba)
for the jagged spires of the Drakensberg Mountains
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Highest mountain of the 'Great Escarpment' in
southern Africa rising to 3000 m, with the
highest peak at Thabana Ntlenyma at 3482 m, the
highest mountain in Africa south of Kilimanjaro
(Tanzania). 'Great Escarpment' lies parallel to
the south-eastern coast of South Africa from the
Eastern Cape extending into Zimbabwe. Separates
southern Africa from the interior plateau. Great
Escarpment initiated during the break-up of
Gondwanaland.
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Called Drakensberg ('dragon mountain') by early
Dutch settlers (Voortrekkers) because of its
resemblance to the ridges of a dragon's
back. Steep ridges of its dragon-like back are
formed by headwater erosion of rivers that
separate the Highveld Plateau from the coastal
lowlands of southern Africa. Less likely, the
name may be derived from an insignificant peak
called Drakensberg or Dragon's Rock. Part of
KwaZulu-Natal of South Africa and Lesotho (
Mountain Kingdom, Basutoland).
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Cathkin Peak
The Sentinel
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The Sentinel
The Amphitheatre
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Location
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28º30' 31º20'S, 27º00' 29º40'E About 40 000
km2 1800 3482 m Drakensberg Alpine Centre or
Region
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Geology and topography
Much of the area lies on the high plateau above
3000 m of Lesotho bounded by the Drakensberg
escarpment to the east, north, and south
extending into South Africa. Mostly formed of
basalt lavas, up to 1400 m thick and forming
sheer cliffs up to 460 m high. Underlain by
Clarens sandstone (up to 2500 m), often undercut
with caves with many Bushman paintings.
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1. North Drakensberg from near Rhodes
2. North Drakensberg and Amphitheatre
3. Clarens Sandstone, Royal Natal National Park
4. North Drakensberg and Devil's Tooth
5. Maletsunyre Waterfall, Lesotho

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Thought to be some of the oldest mountains in the
world. In centre of continent rather than at
edges of continents. At edge of the interior
plateau of southern Africa. With break-up of
Gondwanaland about 200 million years ago, lavas
flowed through fissures and capped the
sedimentary sandstones for about 50 million years
from early Jurassic to the Cretaceous.
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Soils are thin on the basalt plateau almost
non-existent on the escarpment deep on the
Clarens sandstone. Soil pH about 5.5 6.0, very
deficient in N and P, high levels of exchangeable
Al. Summit soils become wet and water-logged in
summer. In winter subject to freezing at night
and thawing by day. Ice-heaved stones, stone
polygons, solifluction terraces, frost hummocks
(thurfur) on the high plateau.
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1. Sani Top Flats, 2900 m
2. Black Mountain, 3100 m

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Climate
Main feature is summer rainfall
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Temperate climate with summer rainfall. Mean
temperature of warmest month at 3050 m ca.
10.9ºC. Mean annual rainfall 635 mm in west to
2000 mm on main plateau. Diminishes in the east
due to the rain-shadow effect. Alpine belt (above
2750 m) is severe with a mean annual temperature
of 5.7ºC. Highest recorded is 31ºC (January
1972), coldest -20.4ºC (June 1967). Half year,
minimum temperatures are below 0ºC.
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Snow cover four months or longer in protected
gullies or south-facing slopes. Frost daily in
winter. Mist common throughout year. Summit winds
important. Very high winds in spring and summer,
especially in afternoons and evenings. Summer
heavy thunderstorms characteristic.
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3050 m altitude

1. Precipitation exceeds temperature climate is
   'humid'
2. Winter has low rainfall and low temperatures

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Temperature chart for 3050 m altitude Mean annual
temperature 5.7ºC 183 days with frost
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Land-use and Fire

• Fire is dominant ecological factor
• Natural caused by lightning usually in spring or
  when boulders roll down and collide with other
  boulders to produce sparks that ignite dry grass
  swards.
• Bushmen burning to produce new grass growth that
  would attract game for hunting.
• Bantu and European farmers burnt grasslands to
  provide winter grazing for sheep and cattle.
• Natural lightning ground-flash density of 12 - 14
  flashes per km2 per year.

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Alpine areas burnt by Lesotho people on fairly
regular annual basis. Summer grazing by cattle,
horses, sheep, and goats. Extreme overstocking of
grazing animals in Lesotho (300
overstocking). Severe soil erosion and inwashing
of silt. Large areas in Lesotho flooded to
provide Lesotho Highlands Water Project for South
Africa. Value about 38 million per year by
2030. Natal Drakensberg produces water worth
about 929 million per year for South Africa.
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1. Maletsunyre Gorge and Fields, 2400 m
2. Lesotho Huts, Semonkang, 2100m
3. Lesotho Horsemen
4. Lesotho Horsemen and pack ponies
5. Basuto Village
6. Village chiefs
7. Hilary and (other!) chiefs
8. Musicians
9. Semonkong 'hotel' hut

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Vegetation
Biomes of southern Africa all in 'grassland'
biome
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In Afromontane and Afroalpine phytogeographical
region
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Montane belt 1280 1830 m Podocarpus
latifolius forest Subalpine belt 1830 2750
m Fynbos ( species-rich heath) now mainly
grassland Alpine belt 2750 3484 m Erica
Helichrysum 'tundra' heath and grasslands
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Debate about what is the 'alpine belt'. Defined
climatically rather than floristically at 2750
2865 m elevation. Called Afroalpine region,
whereas lower levels above 1800 m are Afromontane
region. No real change, gradual floristic
changes, but there is the big escarpment in the
way!
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Extent of alpine belt above 2750 m
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BOTANICAL FEATURESState of Knowledge, Richness,
and Endemics
About 2200 species, 4 endemic genera, 400 endemic
species (ca. 18) Largest families

1. Asteraceae 5. Cyperaceae
2. Scrophulariaceae 6. Orchidaceae
3. Poaceae 7. Ericaceae
4. Iridaceae

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Helichrysum (85) Argyrolobium (18) (Fabaceae)
Senecio (76) Moraea (16) (Iridaceae)
Erica (25) Thesium (15)
Disa (24) (Orchidaceae) Hypoxis (15) (Hypoxidaceae)
Selago (19) (Scrophulariaceae) Kniphofia (15) (Liliaceae)
Crassula (19)
Life-study of Olive Hilliard and Bill Burtt, now
retired but still very active at Royal Botanic
Gardens Edinburgh.
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September 2003
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Visited Drakensberg with Alpine Garden Society 5
20 January 2002 with David McDonald and John
Grimshaw. Saw about 700 species richest area we
have visited! Great show of colourful bulbous
plants, orchids, and composites.
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Has strong affinities with the Cape Floristic
Region as well as the Afromontane Region. Weak
links with the Afroalpine Region of East
Africa. 88 genera in Drakensberg have their
centres of diversity in the Cape Floristic Region
(e.g. Erica, Protea, Helichrysum).
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ALTITUDINAL ZONATION
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Montane Belt
1280 1830 m (lowest visited 1750 m) Podocarpus
latifolius forest Protea savannah Grassland C4
grasses (? result of fire) Cliffs and rock
outcrops
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1. Royal Natal National Park Podocarpus forest, 1750
   m
2. Thamocalamus tesselatus bamboo
3. Peperomia retusa Piperaceae
4. Zantedeschia albomaculata Arum lily Araceae
5. Carex zulensis 16 species
6. Begonia sutherlandii
7. Impatiens hochstetteri Old World Tropics
8. Steptocarpus gardenii Gesneriaceae 200
   or 1 spp
9. Stenoglottis fimbriata Orchidaceae
10. Pteris cretica
11. Gleichenia umbraculifer S. Hemisphere
12. Adiantum poiretii
13. Elaphoglossum drakensbergensis tropical
    America, 400 spp
14. Harveya speciosa Parasitic Scrophulariaceae
    Africa

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1. Golden Gate and scrub, 1895 m
2. Protea roupelliae
3. Cyathea dregei
4. Agapanthus campanulatus Liliaceae 10 spp.
   S. Africa
5. Agapanthus campanulatus
6. Gladiolus crassifolia
7. Berkheya rapontica 75 spp. S. Africa
8. Leonotis leonuris Labiatae 40 spp. Africa
9. Phygelius capensis 2 spp.
10. Zaluzianskya microsiphon 40 spp. Africa
11. Sopubia cana 50 spp. Africa, Himalaya,
    Formosa, Vietnam
12. Striga bilobata Hemiparasite, 40 spp.
    Africa, Asia, Australia
13. Scilla nervosa 40 spp.

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1. Ophioglossum polyphyllum
2. Drosera natalensis 125 spp. 18 in SA, mainly
   NZ or Australia
3. Brunsvigia radulosa Africa, 20 spp.
   Amaryllidaceae
4. Waterfall, Royal Natal National Park, 18450 m
5. Gladiolus microcarpus 150 spp. 100 in S.
   Africa
6. Hilary and Galtonia regalis 4 spp. Liliaceae
7. Galtonia viridflora
8. Royal Natal National Park sandstone cliffs, 1800
   m
9. Asplenium aethiopicum
10. Cheilanthes multifida
11. Crassula umbraticola 300 spp. 280 in S. Africa
12. Crassula pellucida ssp. brachypetala

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Subalpine Belt
1830 2750 m Protea savannah Grassland C4
grasses (? result of fire) Mires, flushes. and
'sponge' bogs Cliffs and rock outcrops
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1. Oxbow, Lesotho 2500 m
2. Protea roupelliae 115 spp. 80 in S. Africa,
   W Cape
3. Protea dracomontana
4. Protea subvestita
5. Dioscorea sylvatica Dioscoreaveae 600 spp.
   semi-tropical, 20 in SA
6. Crassula sarocaulis
7. Bowkeria verticillata Shrub Scrophulariaceae
8. Erica drakensbergensis 650 spp. 600 in SA
   (Cape)
9. Dierama dracomontanum 75 spp. Africa
   Iridaceae
10. Dieranam robustum
11. Naude's Nek 2400 m
12. Moraea alticola 90 spp. 75 in S. Africa
13. Moraea alpina
14. Sandersonia aurantiaca Liliaceae Christmas
    Bells
15. Gladiolus longicollis

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1. Hesperantha grandiflora 60 spp. Iridaceae
2. Watsonia densiflora 70 spp. S Africa
   Iridaceae
3. Watsonia pillandsi
4. Androcymbium striatum 30 spp. 3 in
   Mediterranean
5. Croscosmia pearsii Iridaceae Endemic 9
   spp.
6. Dianthus basuticus
7. Naude's Nek Cliffs 2550 m
8. Nerine bowdenii 22 spp. S Africa only
   Amaryllidaceae
9. Ranunculus baurii
10. Kniphofia ritualis 70 spp. 45 in S Africa
    Liliaceae
11. Kniphofia triangularis
12. Craterocapsa congesta 4 spp. S Africa
13. Wahlenbergia cuspidata 200 spp. mainly S
    Africa
14. Chironia perglerae Gentianaceae 30 spp.
    Africa
15. Cephalaria oblongifolia Dipsaceae
    Mediterranean, Asia, Cape
16. Harpachloa falix Caterpillar Grass
    Monotypic

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1. Hypoxis rigidula Hypoxidaceae 100 spp.
   50 in S Africa
2. Xerophyta viscida Velloziaceae Africa,
   Arabia 28 spp.
3. Geranium multisectum
4. Monsonia brevirostrata Geraniaceae 25 spp.
   Africa
5. Pelargonium alchemilloides 250 spp. S
   Africa
6. Lotononis sericophylla 100 spp. Africa,
   India
7. Lotononis pulchra
8. Sutherlandia montana 6 spp. S Africa
9. Pachycaprus dealbatus Ascelepiadaceae 50
   spp. 24 in S Africa
10. Pachycarpus campanulatus 50 spp. 24 in S
    Africa
11. Selago cf. flanaganii 150 spp. S Africa
12. Jamesbrittenia pristisepala 83 spp. 74 S
    Africa
13. Diascia vigilis 30 spp. S Africa
14. Cycnium racemosum 40 spp. Africa
    Hemi-parasite
15. Alectra capensis Hemi-parasite 40 spp. S
    America, Asia, 10 in SA

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1. Harveya leucopharynx Parasite 40 spp. 25
   in S Africa
2. Rhodes Naude's Nek 2400 m
3. Berkheya cirsiifolia
4. Berkheya purpurea
5. Haplocarpha scaposa 8 spp. Africa
6. Inulanthera calva 10 spp. Africa
7. Senecio macrospermus 2000 spp. 350 in S
   Africa 80 in area
8. Senecio isatidens
9. Senecio gramineus
10. Senecio macrocephalus
11. Senecio polyodon
12. Naude's Nek grassland 2800 m
13. Hirpicum armerioides 12 spp. Africa
14. Gazania krebsiana 16 spp. S Africa
15. Pterygodium magnum 14 spp.

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1. Corycium nigrescens 15 spp.
2. Satyrium neglectum 100 spp.
3. Schizochilus flexuosus 10 spp.
4. Holothrix scopularia 35 spp.
5. Disa nervosa 130 spp. Africa
6. Disa stachyoides
7. Disa crassicornis
8. Disa thodei
9. Disa fragrans
10. Disa versicolor
11. Eucomis autumnalis 10 spp. Africa
    Liliaceae
12. Eucomis bicolor
13. Eucomis bicolor
14. Eucomis schiffii
15. Bulbine capitata 35 spp. mainly Cape
16. Meadow near Semonkong 2200 m

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1. Pharcocapnos pruinosus Fumariaceae 3 spp.
   Africa
2. Argemone ochroleuca Papaveraceae
3. Papaver aculeatum 100 spp. 1 in Africa
4. Kniphofia caulescens Liliaceae
5. Kniphofia caulescens
6. Kniphofia caulescens sun-birds
7. Carex cognata
8. Cyperus spaerocephalus 600 spp. 50 in
   Africa
9. Sponge bogs, Black Mountain 2800 m
10. Eriocaulon dregei var. sonderiana 400 spp.
    12 in Africa
11. Anagallis huttonii 30 spp. 2 in S Africa
12. Utricularia livida 30 spp. 15 in S Africa
13. Crassula papillosa
14. Limosella major 18 spp. 6 in S Africa
15. Gunnera perpensa Gunneraceae 50 spp. 1
    in S Africa
16. Sani Cliffs 1900 m

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1. Cotyledon orbiculata var. oblongata
   Crassulacea 40 spp. Africa
2. Aloe aristata Liliaceae 300 spp. 145 in
   S Africa
3. Aloe polyphylla
4. Aloe polyphylla
5. Euphorbia clavarioides 2000 spp. 200 in A
   Africa
6. Erica reenensis
7. Steptocarpus pusillus
8. Holothrix incurva Orchidaceae
9. Hemanthus humilis ssp. hirsutus
   Amaryllidaceae 21 spp. SA
10. Cyrtanthus epiphyticus Amaryllidaceae 50
    spp. Africa
11. Sebaea natalensis 100 spp. 45 in S Africa
    Gentianaceae
12. Polystichum monticola
13. Ceterach cordatum
14. Cheilanthes hirta
15. Dryopteris athamantica
16. Mohria hirsuta Schizaeaceae

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Alpine Belt
2750 3484 m Alpine heath 'tundra' Alpine
grassland and summit areas Mires and
flushes Aquatic and stream-side communities Cliffs
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1. Ben MacDhui 3001 m
2. Black Mountain, Lesotho 3220 m
3. Macowania sororis 11 spp. 9 in Eastern S
   Africa
4. Euryops montanus 98 spp. S Africa
5. Euryops tysonii
6. Chrysocoma tenuifolia 18 spp. 12 in S
   Africa
7. Erica frigida
8. Helichrysum marginatum
9. Helichrysum milfordiae
10. Sentinel Plateau 3010 m
11. Albuca humilis 75 spp. mainly S Africa
12. Crassula natalensis
13. Massonia cf. echinata Liliaceae
14. Lotononis galpinii
15. Jamesbrittenia jurassica
16. Selago galpinii

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1. Sutera breviflora 130 spp. Africa 1 in
   Canary Isles
2. Diascia fetcaninesis
3. Luzula africana 80 spp. 1 in S Africa
4. Cerastium capense 60 spp. 5 in S Africa
5. Polygala gracilenta 600 spp. 100 in S
   Africa
6. Alchemilla natalensis 250 spp. 20 in S
   Africa
7. Hesperantha radiata Iridaceae 60 spp
   Africa
8. Asclepias humilis
9. Aster eruciformis 250 spp. few in S Africa
10. Felicia rosulata 80 spp. mainly S Africa
11. Delosperma congesta Mesembryanthemaceae
    140 spp.
12. Delosperma lineare
13. Romulea thodei Iridaceae 90 spp. 70 in
    S Africa
14. Manulea parviflora Scophulariacea 60 spp.
    S Africa
15. Sentinel Summit 3010 m
16. Kniphofia fluviatilis

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1. Sentinel Summit pools 3000 m
2. Juncus dregeanus 300 spp. 25 in S Africa
3. Cotula lineariloba 90 spp. 40 in s Africa
4. Alepidea woodii Umbelliferae 25 spp. all
   S Africa
5. Wurmbea elatior Liliaceae 25 spp. Africa
   and Australia
6. Lobelia erinus Campanulaceae 300 spp.
   70 in S Africa
7. Rhodohypoxis baurii var. baurii Hypoxidaceae
   6 spp. SA only
8. Rhodohypoxis baurii var. confecta
9. Crassula drakensbergensis
10. Isolepis fluitans 40 spp. 30 in S Africa
11. Aponogeton junceum Aponogetonaceae 25 spp.
    Africa, Asia, Australia 5 in S Afric
12. Lagarosiphon muscoides Hydrocharitaceae 16
    spp. 5 in S Africa
13. Sani Top 3100 m
14. Ben MacDhui 3001 m

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1. Devil's Tooth, Sentinel
2. Teguela Falls
3. Steel ladders, Sentinel Escarpment
4. Gladiolus flanaganii
5. Euryops evansii
6. Woodsia montevidensis 40 spp. 1 in S Africa
7. Diascia cordata
8. Diascia stricta
9. Nemesia rupicola 70 spp Africa
10. Crassula setulosa var. curta
11. Glumicalyx goseloides 6 spp. Drakensberg
    only
12. Tiffendall Ski Resort 2873 m
13. Sani Pass Transport
14. Sani Chalet 2900 m

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THE BIG TAXONOMIC HEADACHE HELICHRYSUM!

• Mainly African genus, some in Mediterranean
  Europe, SW Asia, S India, Sri Lanka, Australia
• 600 species, 245 in South Africa, 85 in
  Drakensberg, found 60
• Herbs, climbers, low shrubs
• Grasslands, woodland, scrub, cliffs, screes,
  wind-blasted open grassland, rock outcrops, mesic
  areas

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1. Helichrysum montanum
2. H. marginatum
3. H. milfordiae
4. H. pagophilum
5. H. vernum
6. H. bellidiastrum
7. H. tenuifolium
8. H. witbergense
9. H. trilineatum
10. H. ecklonis
11. H. confertiflium

1. H. aureoniteus
2. H. aureum
3. H. albo-aureum
4. H. herbaceum
5. H. flanaganii
6. H. panduratum
7. H. acutatum
8. H. krokii
9. H. hypoleucum climber
10. H. drakensbergense
11. Hilary and H. montanum

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WHY SO RICH?
Drakensberg is an international 'hot-spot' of
plant biodiversity, not only of vascular plants
(2200 species) but also of bryophytes (over 1000
species). Nothing known about vegetational
history. Endemics (18) are mixture of
palaeo-endemics and neo-endemics. Some major
disjunctions (e.g. Macowania Drakensberg,
Ethiopia, Yemen Thamnocalamus Drakensberg,
east Asia).
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Small area ca. 40 000 km2 (? Belgium) Possible
contributory factors for high diversity

1. Centuries of low-intensity ('intermediate')
   disturbance from Bush-people.
2. Soils are infertile but not strongly acid and
   high in Al.
3. Mixture of floristic elements (Cape, Afromontane,
   etc.)
4. Altitudinal range of over 2000 m.
5. Climatic gradients within 1500 m from alpine
   periglacial features to lush Podocarpus forest
   with Streptocarpus.
6. Topographical diversification into distinct
   valleys and watersheds, favouring isolation of
   species.
7. Fine-scale topographical variation with springs,
   flushes, soaks, mires, etc. within well-drained
   grassland.

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CONSERVATION AND THE FUTURE
3 in Lesotho and 97 in Natal Drakensberg are
protected as Nature Reserves, National Parks, and
Wilderness Areas. Major threats by overstocking
and soil erosion in Lesotho. Also threats from
invasive exotic plants and clearance for crops in
an area very poorly suited to arable agriculture
in Lesotho. At present alpine areas (nearly all
in Lesotho) are unprotected. Urgent need for
whole areas as Biosphere Reserve or World
Heritage Site. But conservation is not the major
problem facing southern Africa
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Besides problems of overstocking, soil erosion,
and hydroelectric development in Lesotho, major
threat is from 'global warming'.
McDonald et al. (2002) defined climate envelopes
for 16 alpine species today, to define the modern
'alpine' climate.
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Predicted the extent of the 'alpine' climate
under future scenario of IPCC for 2150. See major
reduction in 'alpine' climate, confined to the
few highest areas. Would become very fragmented.
Major loss of species. Much reduced snow cover,
loss of available water. Major ecological and
economic effects.
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1. David MacDonald and John Grimshaw
2. Amphitheatre, Witsishoek 0430 hours

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Thanks John Grimshaw Bill Burtt David
McDonald Olive Hilliard Else Pooley Cathy Jenks