Kouebeskadiging van houtagtige plante in die Suuragtige‐Gemengde Bosveld

Abstract

Cold damage to woody plants in the Sourish Mixed Bushveld. An incident of damage to woody plants by cold in the Sourish Mixed Bushveld was investigated. Woody plants in eight paddocks which were subjected to long‐term grazing treatments and which gave rise to different tree densities, were examined. The most common form of damage was top kill, and these plants subsequently coppiced from the base. Four woody species, namely Dichrostachys cinerea (the dominant woody species in the area), Acacia nilotica, A. gerrardii and A. robusta were severely damaged by the cold. The greatest effect was on trees in a certain height range; 1,0–3,0 m in the case of D. cinerea and 0,5–2,0 m in the case of the Acacia species. There was a negative curvilinear relationship between the number of trees larger than 2,0 m per hectare and the percentage damage. In paddocks where the tree density was relatively low the number of tree equivalents (equivalents of a tree 1,5 m high) was reduced by as much as 30%.

‘n Geval van kouebeskadiging van houtagtige plante in die Suuragtige‐Gemengde Bosveld is ondersoek. Houtagtige plante in agt kampe wat aan verskillende langtermyn beweidingsbehandelings onderwerp is, en wat tot verskillende boomdigthede aanleiding gegee het, is ondersoek. Die mees algemene vorm van beskadiging was bogrondse plantdele wat gedood is, met daaropvolgende basale hergroei. Vier houtagtige spesies, naamlik Dichrostachys cinerea (die dominante houtagtige spesie in die gebied), Acacia nilotica, A. gerrardii en A. robusta, is hewig deur die koue beskadig. Die grootste effek was op bome van ‘n bepaalde hoogtereeks; 1,0–3,0 m in die geval van D. cinerea en 0,5–2,0 m in die geval van die Acacia spesies. Daar was ‘n negatiewe kurwilineêre verwantskap tussen die aantal bome groter as 2,0 m per hektaar en die persentasie beskadiging. In die kampe met relatiewe lae boomdigthede is die aantal boomekwivalente (ekwivalente van ‘n boom 1,5 m hoog) met tot soveel as 30% verminder.

Additional index words:

• Coppice growth
• relationships
• tree density