Trees for the Western Transvaal selected on the basis of arboretum trials
Date
1968-03
Authors
Poynton, R. J.
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : Stellenbosch University
Abstract
ENGLISH ABSTRACT: Trees are needed on the semi-arid Highveld of
the western Transvaal for shelterbelts, woodlots, fodder,
honey, shade and ornament.
A brief history of tree planting in the area,
more particularly at Lichtenburg and Potchefstroom, is
given.
Relatively few species can be grown successfully in the western Transvaal because of the unfavourable
climate. Hot, dry winds blow almost continuously off
the Kalahari between August and October before the first,
spring rains; cold winds and frosts are experienced in
winter, although the summers are hot; the rainfall is
erratic and low, averaging about 600 mm. a year and
occurring mainly in the form of heavy thunderstorms
during summer; hail is common.
The geology of the area is complex. In the
north-west an overburden of wind-transported sand obscures
the underlying formations. The soils are mostly of a
light, sandy or loamy consistency, with a fairly high
base-saturation value. Concretions, sometimes forming
a continuous hardpan, are characteristic of certain
types.
Various indigenous trees are found in some
localities. These are small,and are mainly confined to
rocky hillsides and stream banks. In the past they have
been much exploited for rough building timber, fence posts
and firewood. Their growth is very slow, and exotics
have proved to be more vigorous as well as more useful
in cultivation.
Possible adaptations of trees to dry climates
are discussed. It is concluded that'apparent adaptations
observed in the field are of little value in selecting
trees for dry areas. No practical alternative therefore
exists at this stage to the introduction of species from
.areas with a similar climate and testing these under
local conditions. Parts of the world having a climate
similar to that of the western Transvaal are in.dicated.
Summarised results of species trials in the
western Transvaal are given in tabular form, and recommendations
for tree planting in the area are made.
In an appendix, trials of BB species in
arboreta at Lichtenburg and Potchefstroom are fully
described and discussed.
Description
Thesis (MSc)--Stellenbosch University, 1968.
Keywords
Arboriculture -- South Africa -- Transvaal, Western, Trees -- South Africa -- Transvaal, Western, Dissertations -- Forest and wood science, Theses -- Forest and wood science