Economic analysis of using sheep to control leafy spurge

Leafy spurge (Euphorbia esula L,), a widely established exotic, noxious, perennial weed, is a major threat to rangeland and wildland in the Upper Great Plains. A deterministic, bioeconomic model, incorporating relationships between sheep grazing and leafy spurge control, grass recovery, and forage consumption by cattle, and expected costs and returns from sheep enterprises was developed to evaluate the economic viability of using sheep to control leafy spurge, Various scenarios were developed depicting likely situations facing cattle ranches adding a sheep enterprise for leafy spurge control, Two levels of flock profitability, one based on a level of proficiency achieved by established sheep ranches and one substantially low er than typically achieved in the sheep industry, were combined with debt and no-debt to represent best- and worst-case scenarios, respectively. In the best-case situations, using sheep to control leafy spurge was economical in all of the scenarios examined. In the worst-case situations, the economics of using sheep to control leafy spurge were mixed across the scenarios examined, Leafy spurge control with poor flock proficiency, high fence expense, and unproductive rangeland generally was not economical. Situations with low fencing costs, moderately productive rangeland, and poor flock proficiency resulted in less economic loss than no treatment. Actual returns from leafy spurge control for most ranchers will likely fall between the extremes examined.