Afforestation is the planting
of trees for commercial purposes, usually on land
supporting non-forest veld types, e.g. grassland
or fynbos. This differs from reafforestation
which is the restocking of existing forests and
woodlands which have been depleted.
Less than 0,5% of South Africa
is covered by indigenous forests. Owing to their
slow growth and sensitivity to logging, these
forests cannot supply the majority of our
country's wood requirements. Additional
fast-growing trees are planted to cater for the
demand for wood products. Commercial forests, or
plantations, cover 1,1% of South Africa.
AFFORESTATION IN SOUTH AFRICA
* Pines, originally from the N. Hemisphere, make
up 51% of the total commercial afforestation
(TCA) in SA and are mainly used for sawlogs,
veneer and pulpwood.
* Gum trees from Australia make
up 38,9% of the TCA and are used for poles,
mining timber, paper pulp and charcoal.
* Black wattle from Tasmania
makes up 9,5% of the TCA and is used for tannin,
paper pulp, mining timber and charcoal.
* Other trees make up the final
0,6% of the TCA.
Only 16% of South Africa,
mainly the wetter eastern parts, is climatically
suited to afforestation. In many cases the
climate is extremely favourable and local pines
grow at two to three times the rate of those in
Europe or North America, where they originated.
Alien tree species (e.g. pines
and gums) used in local afforestation do well in
South Africa because they are not attacked by the
insect pests and plant diseases which affect the
trees in their country of origin. Careful
breeding has also improved the growth
characteristics of the species used in commercial
forestry resulting in higher yields of wood per
hectare. Today South Africa exports close to 2
million tonnes of wood and wood products.
The increasing demand for fuelwood and building
material in rural areas has caused widespread
deforestation of natural woodlands, riverine
zones, and water catchments. To reduce this
problem woodlots have been established at a
number of villages throughout the country to
supply fuelwood and poles. Many woodlots make use
of wattle and gum trees and now cover a total
area of roughly 14 000 ha in South Africa.
The incorporation of trees with
crops, a system known as agroforestry, is one
method of increasing fuelwood production that is
gaining popularity in Third World countries.
Trees grown amongst crops supply timber, nuts,
fruit, and fodder for cattle. Appropriate species
of trees enrich the soil, prevent erosion, retain
water, and shield crops from damaging wind and
AFFORESTATION AND THE
The supply of wood and wood products from
afforested areas has prevented the
over-exploitation and destruction of our
indigenous forests. However, unwise planning and
management of afforestation can lead to negative
Habitats most severely affected
by afforestation include wetlands, grassland,
fynbos and indigenous forests. Good management,
and planning that takes conservation of natural
habitats into consideration, can overcome these
problems, some of which are outlined below:
situated too close to wetlands and perennial
streams, or in their catchments, leads to their
eventual drying out as trees use large amounts of
water. The endangered wattled crane is dependant
on wetlands for breeding (see Enviro Facts
Grasslands: These rich
communities support a variety of animals,
including threatened species such as oribis,
Stanley bustards and blue swallows. Afforestation
converts grasslands to plantations, and so these
animals lose their `home' (see Enviro Facts
Fynbos: this unique
habitat of the western Cape is also seriously
affected by the invasion of alien trees from
plantations (see Enviro Facts
When plantations next to indigenous forests are
logged, trees may fall onto the forest margin and
damage it. Once damaged, the forest margin can no
longer protect the indigenous forest from fire.
In addition, logging can destroy the diverse
habitat where forest and grassland meet. The
forest margin is an important food source for
many forest animals, e.g. bushbucks shelter in
the forest but feed mainly on the smaller plants
in the forest margin.
River catchments: Trees
use large amounts of water. Afforestation in
water catchments thus reduces runoff and water
availability for other uses (see Enviro Facts
AFFORESTATION AND THE
Trees absorb carbon dioxide (CO2) from the
atmosphere during photosynthesis. It has been
suggested that large scale afforestation could
successfully absorb the CO2 generated by the
burning of the fossil fuels, coal and oil. The
vast areas of afforestation required to achieve
this would result in many negative environmental
impacts. From a local perspective, in the short
term such afforestation would cause as much
environmental destruction as global warming could
in the long term.
A better approach would be to
tackle this problem at its roots: reduce our
reliance on fossil fuels and prevent
deforestation of our natural forests. Fossil fuel
combustion and deforestation together account for
the majority of man-made CO2 releases (see Enviro
Facts "Global Warming").
DID YOU KNOW?
* In South Africa alien commercial forests cover
about 3,5 times the area (almost 1,2 million ha)
covered by indigenous forests (330 000 ha).
* Fifty-one per cent of
commercial plantations are found in the former
Transvaal and Orange Free State, 38% in
KwaZulu/Natal, and 11% in the three Cape
* Plantation forestry started
in South Africa in about 1888.
TREES OF SOUTHERN
AFRICA. Keith Coates Palgrave. Struik,
Cape Town. 1988 Southern Cape
FORESTS AND TREES.
F. Von Breytenbach. Government Printer, Pretoria.
HOW TO GROW YOUR OWN
TREES. J.H. Scriba. and H.L. Gerber.
Pamphlet 109, Branch Forestry, Dept. of Water
Affairs and Forestry, Pretoria. 1973.
TREES IN URBAN AREAS.
J. Voslos Jordaan. Pamphlet 108, Dept. Water
Affairs and Forestry, Pretoria. 1973.
Trees for Africa.
P.O Box 2035, Gallo Manor, 2000. Tel.011-803
Forestry Branch, Dept.
of Water Affairs and Forestry. Private
Bag X313, Pretoria, 0001. Tel. 012-299 91117.
Faculty of Forestry.
University of Stellenbosch, Stellenbosch, 7600.
Saasveld School of
Forestry. P/Bag X 6531, George, 6530.