The economics of controlling gorse in hill country : goats versus chemicals

Abstract

The aim of this study was to assess the economics of controlling gorse in hill country by comparing the use of goat and sheep grazing with chemical control. The New Zealand environment has suited the growth of gorse (an introduced species) to such an extent that this plant has become a major weed problem throughout New Zealand. Traditionally, gorse has been controlled by spray programs, but this method is costly and has met with limited success. Recent research has shown the grazing of goats and sheep to be a possible alternative for gorse control. A simulation model was constructed which includes the physical and economic aspects of a hill country grazing system. Extensive sensitivity analysis and experimentation were carried out using the model to evaluate alternative control strategies under different price and production scenarios. These control options were assessed under a range of goat grazing rates, and were compared with the traditional burn and spray method of gorse control. The study concludes with a discussion of the results given both short and long term market expectations, including some consideration of future research priorities in this field.