Towards reduced herbicide use in forest vegetation management

Abstract

Mechanical, manual, thermal, biological and chemical methods of managing forest vegetation have, to a large extent, been developed independently. The effectiveness and relatively low cost of chemical herbicides, however, have led to systems of vegetation management that rely on their continued availability and the near exclusion of non-herbicide methods for controlling forest weeds. Greater public concern, perceptions of risk, and pressures exerted by some forest certification systems, have increased the need to provide a wider array of alternative methods that can reduce dependence on herbicides. In response, forest vegetation management research has widened to include investigations of alternatives to herbicides, along with initiatives aimed at reducing chemical use. An international review of progress indicates that reduced herbicide use may already be possible in many countries. There are however, a number of commercial, economic and social issues associated with the practical application of this knowledge, notwithstanding the fact that a more integrated approach is required to combine relevant methods of vegetation management, rather than attempting to practise alternative techniques in isolation from other silvicultural practices. This paper, together with appropriate examples, reviews pressures to reduce herbicide use as well as past and current research to develop alternatives to herbicides in eleven different countries, as well as identifying instances of the successful or unsuccessful implementation of this technology.

Keywords: weed control, integrated forest vegetation management, herbicide alternatives, certification

Southern African Forestry Journal Vol. 207 2006: 63-79