Main Article Content

The coppicing ability of Acacia erubescens and Combretum apiculatum subsp. apiculatum in response to cutting


GN Smit

Abstract

The investigation was conducted in the Limpopo Province of South Africa.
Twenty single stemmed trees of both Acacia erubescens
and Combretum apiculatum subsp. apiculatum were randomly selected
and five trees of each species were cut at heights of 5cm, 15cm, 30cm
and 45cm above ground level. At the end of the following five growing
seasons leaf dry mass estimates were calculated using the BECVOL-model.
Both species coppiced vigorously, but C. apiculatum achieved
a higher leaf dry mass production (mean of 875g tree-1
) in comparison
to A. erubescens (mean of 608g tree-1).
In the case of A. erubescens the leaf dry mass production at
the end of the 5-year trial period varied from a minimum of 460g tree-1 at a cutting height of 5cm to a maximum of 768g tree-1at a cutting height
of 15cm. In the case of C. apiculatum it varied from a minimum
of 668g tree-1 at a cutting height of 15cm to a maximum of 1 074g tree-1
at a cutting height of 30cm. The effect of the cutting height on the subsequent
height of the coppice growth differed between the two species. In the
case of A. erubescens the total height of the coppice growth
differed significantly between plants that were cut at different heights,
but not in the case of C. apiculatum. The cutting height had
no significant effect on the leaf dry mass production of both species.
Despite the lack of statistically significant differences, the leaf dry
mass production tended to be higher with an increase in cutting height.
Depending on the cutting height, the A. erubescens trees will
regrow to their original leaf biomass (average of 1 429.7g tree-1) within
5.9 to 9.4 years (seasons) and the C. apiculatum trees (average
of 1 748.9g tree-1) within 7.1 to 15.8 years (seasons).

Keywords: browsers; bush encroachment; leaf dry mass production; savanna; tree thinning

African Journal of Range & Forage Science 2003, 20(1): 21–27

Journal Identifiers


eISSN: 1727-9380
print ISSN: 1022-0119