TOWARDS AN ECONOMIC FRAMEWORK FOR EVALUATING POTENTIAL BENEFITS FROM RESEARCH INTO WEED CONTROL

Abstract

A dynamic economic model for estimating benefits from research into alternative tactics for weed control is developed, by treating weeds as renewable negative resources. Research benefits are evaluated as the change in steady‐state profit resulting from research‐induced changes in various parameters of the system. The model is illustrated by application to research aimed at the control of wild oats in wheat in Australia, whereby it was found that the magnitude of benefits depended not only on the level of research‐induced change but also on demographic behaviour of the weed. Research leading to reductions in seedling survival, potential fecundity or recruitment gave higher benefits than the manipulation of weed competitiveness or seed mortality. Reduced seedling survival gave the highest benefits in most cases, but achieving such improvement by improving herbicide efficacy may have a high marginal cost given that the tactic is already well‐researched. Thus it is concluded that research into reducing potential fecundity could be more worthwhile, since it also gave high benefits but is relatively unexplored.