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Grasslands (also
known locally as Grassveld) are dominated by a
single layer of grasses. The amount of cover depends
on rainfall and the degree of grazing. Trees are
absent, except in a few localized habitats.
Geophytes are often abundant. Frosts, fire and
grazing maintain the grass dominance and prevent the
establishment of trees.
There are two categories of grass plants: sweet
grasses have a lower fibre content, maintain their
nutrients in the leaves in winter and are therefore
palatable to stock. Sour grasses have a higher fibre
content and tend to withdraw their nutrients from
the leaves during winter so that they are
unpalatable to stock.
At higher rainfall and on more acidic soils,
sour grasses prevail, with 625 mm per year taken as
the level at which unpalatable grasses predominate.
C4 grasses dominate throughout the biome, except at
the highest altitudes where C3 grasses become
prominent.
Grass plants tolerate grazing, fire, and even
mowing, well: most produce new stems readily, using
a wide variety of strategies. Overgrazing tends to
increase the proportion of pioneer, creeping and
annual grasses, and it is in the transition zones
between sweet and sour grass dominance that careful
management is required to maintain the abundance of
sweet grasses.
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The Grassland Biome is the mainstay of
dairy, beef and wool production in South
Africa. Pastures may be augmented in wetter
areas by the addition of legumes and sweet
grasses.
The Grassland Biome is the cornerstone
of the maize crop, and many grassland types
have been converted to this crop. Sorghum,
wheat and sunflowers are also farmed on a
smaller scale.
Urbanisation is a major additional
influence on the loss of natural areas - the
Witwatersrand is centred in this biome. The
Grassland Biome is considered to have an
extremely high biodiversity, second only to
the Fynbos Biome. Rare plants are often
found in the grasslands, especially in the
escarpment area. These rare species aria
often endangered, comprising mainly endemic
geophytes or dicotyledonous herbaceous
plants. Very few grasses are rare or
endangered. The scenic splendour of the
escarpment region attracts many tourists.
(Source: "The Vegetation of South
Africa, Lesotho and Swaziland", South Africa
Department of Environmental Affairs and
Tourism)
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