ECONOMIC ISSUES RELATING TO WEED MANAGEMENT IN NATURAL ECOSYSTEMS: THE CASE OF SCOTCH BROOM ON BARRINGTON TOPS, NSW

The area of the imported weed Scotch Broom (Cytisus scoparius) is steadily expanding and eliminating natural ecosystems and their habitats of rare and endangered species in Barrington Tops National Park. A research project, funded by the CRC for Weeds Management Systems, has commenced to provide economic information to assist the management of this problem. To provide a focus for the project, the economic issues surrounding the broom problem are explored in this paper. The general economic characteristics of weeds in natural ecosystems are discussed first, and include externalities and public goods. The economic issues in weed management are addressed next, and include the problems of government management, choice of control measure, and sources of funding. In the case of broom on Barrington Tops, specific economic issues include the allocation of funds to protect rare and endangered species, and difficulties of guaranteed continuous funding. Other issues include; common boundaries and interactions with private landholders and with State Forests, the spread of broom through recreation activities, severe topography and landscape which restricts the range of possible control measures, the persistence of seed banks, and growth habits of broom that limit growth of natural species. The major questions to be resolved appear to include the specification of the utility functions of decision makers; the allocation of funds between containment of broom, preservation of biodiversity, and management of new forest areas; the estimation of a damage function (to show how the spread of broom and loss of habitats is affected by management and biophysical factors); and the choice of economically-efficient versus technically-effective methods of control