are restricted to frost-free areas with mean annual rainfall of
more than 525mm in the winter rainfall region and more than 725
mm rainfall in the summer rainfall region. They occur from sea level
to over 2100m above sea level. Forests rarely burn, mainly due to
the high humidity - under extremely hot and dry (berg wind) conditions
fires may occur and destroy the forest structure.
Forests tend to occur in patches, few of which cover areas greater
than 1 km 2, with areas greater than this only common along the
Garden Route and Lowveld Escarpment. Even added together, forests
cover less than 0.25% of southern Africa's surface area, making
this the smallest biome on the subcontinent.
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.
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. Some forests were removed for the establishment of
exotic plantations. A major plant invader of forests is Blackwood
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 poillinators to move along the corridors between forest patches.
Thus the proclamation of isolated stands of forests as reserves
may be insufficient for their conservation. Sustainable use of forests
may require that their fauna be effectively conserved!
Data for Swaziland were not available.