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Forests tend to occur in patches, few of which cover areas greater than one square
kilometre. Areas greater than this only occur in the higher and wetter parts of Zululand such as
Nkandla and Ongoye. Even added together, forests cover less than 0.25% of Southern Africa's surface
area, making this the smallest biome on the subcontinent. Alberta magna Albizia adianthifolia
Celtis africana Curtisia dentata Cussonia spicata Ekebergia capensis Newtonia hildebrandtii Ocotea
bullata Podocarpus falcatus Pteleopsis myrtifolia Strelitzia nicolai.
The canopy cover of forests is continuous, comprising mostly evergreen trees, and beneath it
the vegetation is multi-layered. Herbaceous plants, particularly ferns, are only common in the
montane forests, whereas lianas and epiphytes are common throughout. The ground layer is almost
absent due to the dense shade. On the edges of the patches are distinctive communities, the
so-called fringe and ecotonal communities, which are able to tolerate fire. Forests rarely burn,
mainly due to the high humidity but under extremely hot and dry (berg wind) conditions fires may
occur and destroy the forest structure. Some 649 woody and 636 herbaceous plant species are
recorded from forests, however, forests are not floristically uniform. Three separate forest types
are recognized in this account. Specialized forests that occur in small areas and very sporadically
- such as mangrove, swamp and fringe forests are not separated from these three types.
Partly because of their rarity, their grandeur and their setting, forests are an important
tourist attraction in South Africa. They have been exploited in the past for valuable timber,
including Black Stinkwood (Ocotea bullata) and Outeniqua Yellowwood (Podocarpus falcatus).
Forest conservation has two facets. The maintenance of components and critical processes in the
forests, which requires the conservation of the large mammals and birds which disperse seeds and
maintain gap processes which allow succession within the forests, and the maintenance of gene flow
which requires allowing seed dispensers and poilinators to move along the corridors between forest
patches.
Coastal Forest
Develops where rainfall is usually greater than 700 mm per year, and is more prevalent in
summer rainfall regions. Temperatures are never extreme due to the moderating maritime influence
and species distributions may be limited in the south by the colder climates. Apart from rainfall
and temperature, important environmental parameters are wind and salt spray. The tall trees may be
severely 'pruned' by high winds and salt damage and this restricts the distribution of forest on
exposed dunes. In its best-developed form Coastal Forest has trees up to 30 m tall and distinct
strata of trees, shrubs and herbs. The higher rainfall and more stable climate allow a richer
forest flora than that of Afromontane Forest. Dune Thicket is found in more exposed situations, and
reaches forest proportions only in sheltered areas, such as behind dunes. Coastal Forest is
well-conserved in reserves in KwaZulu-Natal such as Harold Johnson, Vernon Crookes, Charters Creek,
Maphelana, Cape Vidal, and Ongoye.
Afromontane Forest
Patches of forest with Afromontane floristic affinities occur all along the Drakensberg
mountain chain at altitudes from 800m up to 2100m. They occur on south-facing ridges and in ravines
where moisture is higher and the maximum effect of the south-westerly and south-easterly
wind-driven rains is apparent. Forests of this region range from small to extensive patches on
mountain-sides depending on locality and variation in aspect, geology and soils.
Rainfall is generally greater than 700 mm per year, occurring during summer. Temperatures can
be extreme in some of the higher altitudes where snowfalls may occasionally occur. Trees can be up
to 30 m or 40 m tall and distinct strata of emergent trees, canopy trees and shrub and herb layers
are present.
As is evident from the way the forest is confined to kloofs and gullies, water is a key
limiting factor. However, Afromontane Forest would certainly spread into both grasslands and Fynbos
were it not for fires. All forest patches are in fire-safe habitats with the largest stands
occurring in moist valleys.
Sand Forest
This is confined to the tropical and subtropical coastal belt of KwaZulu-Natal as far south
as the Greater St Lucia Wetland Park.
Sand Forest is distinctive in the preponderance of deciduous to semi-deciduous elements,
especially in the canopy. They form dense, almost impenetrable stands, up to 25 m tall.
Ndumo, Mkhuze Game Reserves, Sodwana State Forest , Tembe Elephant Park and False Bay Park contain
examples of Sand Forest. With grateful thanks to Elsa Pooley's Trees of Natal and Wildflowers of
KwaZulu-Natal, Rob Scott-Shaw's Rare and Threatened Plants and Tainton, Bransby and deV. Booysen's
Common Veld and Pasture Grasses of Natal.
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