Role of fire in preventing bush encroachment in the Eastern Cape

Abstract

A serious bush encroachment problem has developed in the Eastern Cape and it has been suggested that this is partly the result of the elimination of regular, fierce veld fires. The author is of the opinion that it was rather the interaction of burning and wild browsing animals that played the major role in maintaining the original grasslands and preventing the encroachment of bush in the past. After a controlled burn had been applied to an area of dense, sweet grassveld. moderately encroached by Acacia karroo and other bush species, most of the bushes suffered a kill of stems and branches but coppiced from the base of the stem. Stocking lightly with goats controlled this coppice growth with no detrimental effect to the grass. These results indicate that a system of burning and browsing could be used in combatting bush encroachment in certain situations.

Uittreksel

Bosindringing neem ernstige afmetings aan in Oos‐Kaapland. Daar word beweer dat hierdie probleem die gevolg is van onder andere die afwesigheid van gereelde intense veldbrande. Die skrywer is van mening dat in die verlede dit eerder die interaksie tussen veldbrand en beweiding deur wilde struikvreters gewees het wat verantwoordelik was vir die voorkoming van bosindringing en die gevolglike handhawing van ‘it oop grasveld. Volgens die resultate verkry in ‘n proef waar beheerde veidbrand toegepas is in ‘n oop grasveld wat matig deur Acacia karroo en ander bossoorte ingedring is, blyk dit dat die bogroei van die meerderheid bosse grootliks doodgebrand is, terwyl hergroei vanaf die basis van die stamme plaasgevind het. Die hergroei kon egter doeltreffend deur ‘n ligte belading met bokke beheer word sonder enige nadelige effek op die grasbedekking. Hierdie bevindings toon dat ‘n stelsel van brand en beweiding deur bosvretende diere onder sekere toestande aangewend kan word ter‐bestryding van bosindringing.