The effects of pruning on shoot production and basal increment of Acacia tortilis

The shoot production of pruned, felled and undamaged Acacia tortilis trees on an old land site in the northern Transvaal was compared over two growing seasons. Trees were tolerant of damage and continued to increase in size when all current season’s shoots were removed. Basal increment of treated pruned trees was less than controls. Shoot production, relative to basal area, increased after winter pruning and decreased after summer pruning. Shoot production and basal increment were positively correlated with rainfall and indicators of soil moisture. Replacement shoots of pruned trees had a higher moisture content and leaf mass in the dry season and were more thorny than shoots of undamaged trees. Die lootmassa van gesnoeide, afgekapte en onbeskadigde bome van Acacia tortilis is oor twee groeiseisoene, in ’n ouland in die Noord-Transvaal, vergelyk. Die bome was bestand teen beskadiging, en alhoewel alle nuwe lote verwyder is, het die bome nog steeds in grootte toegeneem. Die toename in basale area van gesnoeide bome was minder as die van die kontrole. Die lootproduksie in verhouding tot die basale area, het na ’n winter-snoei toegeneem, maar na ’n somer-snoei afgeneem. Lootproduksie en basale area-aanwas is positief gekorreleer met reënval en ’n indeks van grondvog. Snoei vermeerder doornagtigheid en droëseisoen-voginhoud en blaarrykheid van die lote.