Returns to grasshopper control on rangelands in southern Alberta

Economic injury levels (EILs)—the minimum density of insects that would be required to warrant treatment—were estimated for the 4 most common insecticides sprayed on grasshoppers in Alberta. The results indicate that under the assumed conditions spraying was rarely profitable unless the pests were at very high outbreak levels (>30/M2), the benefits of control lasted more than 1 season or the producers' treatment costs were substantially subsidized by a provincial government rebate program. Estimates vary considerably depending on several parameter values. The most important variables were the cost, life, and efficacy of treatments, the derived price of forage, and assumptions regarding grasshopper population dynamics.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact lbry-journals@email.arizona.edu for further information.Migrated from OJS platform August 202