Bush control: The control of Brachystegia boehmii and Colophospermum mopane in Rhodesia using a picloram/2, 4-D mixture.

Abstract

Mature Brachystegia boehmii and Colophospermum mopane trees were treated with Tordon 101 (a 1: 4 mixture of picloram and 2, 4-D) at five rates and at three different times of the year. The arboricide was applied with a syringe to freshly cut stem tissues, either to cuts in the bark, or to the lower lip of ringbarked trees or (in various ways) to cut stumps. Some treatments were repeated at several sites. Responses to arboricide were not markedly influenced by the method of application. Overall, prising the bark from the wood of cut stumps and placing arboricide in the gap so formed, resulted in the highest percentage kills. Applications were most effective in the growing season (November to March).Medium sized trees were more rapidly killed than smaller or larger ones. Response to arboricide varied between sites.

Keywords: 2, 4-d; arboricide; brachystegia boehmii; bush control; colophospermum mopane; cut stem; method; mopane; picloram; rhodesia; treatments; trees; zimbabwe