Preliminary observations on the ability of goats to control post‐burning regrowth in acacia nigrescens/combretum apiculatum Savanna in Botswana

Abstract

A ten hectare block which had been burned with an intense surface head fire was stocked at the rate of one goat per hectare to control the woody regrowth. After one year the block was subdivided and in one half the stocking rate increased to three goats per hectare. After two further years there was insufficient forage to sustain the high stocking rate. At this stage the bush density below two metres had been reduced by 23% and 52% in the low and high stocking rates respectively. Similarly the bush canopy below two metres had been reduced by 70% and 95%. There was greater mortality of benign browse species than of spinescent species. Adverse changes in herbaceous layer composition were recorded in the high stocking rate. Drought, stocking rate and plant tolerance to browsing are discussed in relation to management objectives.

Uittreksel

‘n Blok van tien hektaar wat deur ‘n hoe intensiteit oppervlakkig voorvuur gebrand is, het ‘n veebelading van een bok per hektaar ontvang om die hergroei van die bos te beheer. Na een jaar is die blok in twee dele verdeel en op die een helfte is die veebelading verhoog na drie bokkeper hektaar. Na twee jaar was daar on‐voldoende voer om die hoe veebelading te dra. Op hierdie stadium was die bosdigtheid onder twee meter onderskeidelik verminder met 23% en 52% in die lae en hoe veebeladings. Eweneens is die boonste verspreiding van die bos onder twee meter verminder met onderskeidelik 70% en 95%. Daar was groter vrekte van vreetbare bome sonder dorings as dié met dorings. Die hoe veebelading het nadelige veranderings veroor‐saak in die samestelling van die graslaag. Droogte, veebelading en plant weerstandsvermoe teen ontblaring word bespreek ten opsigte van bestuursdoelstellings.

Additional index words:

• Bush canopy
• bush density
• species composition