Economics of alternative insecticide treatments and pollinators in Winter canola

Abstract

AbstractIn the US central and southern Great Plains, canola (Brassica napus) is a winter annual crop. It is pollinated by insects, particularly native bees and introduced honeybees (Apis mellifera Linnaeus, 1758). Canola is beset by many insect pests. Producers rely on insecticides to kill harmful insects, however, these chemicals can negatively impact pollinators. Our purpose is to provide an economic analysis comparing the positive effects of native bees and introduced honeybees in combination with the pest suppression effects of selective and broad-spectrum insecticides in Oklahoma canola production. We identify the breakeven yield necessary to support the conservation of pollinator habitat in or adjacent to canola fields. Using yields from field experiments, we found that an increase in yield ranging from 28.02 to 162.53 kg/ha from pollination justifies the conservation of pollinator habitat. The number of refuge acres and canola acres dictates the necessary yield increase. Our findings suggest that introducing honeybees for pollination of canola may not be an economically viable choice as pollination services are costly. We include analysis with the base rate of pollination service rate reduced to more closely examine this issue. The breakeven analysis with the reduced rate shows a range of 2.43 to 19.06 hectares of refuge area was needed. This analysis varies with annual crop returns and acres of canola planted. This study provides a deeper understanding of the costs and potential benefits associated with pollinator refuges and canola production and allows producers to make more informed decisions about wild pollinators and reliance on introduced honeybees.

Keywords

• canola
• honeybees
• native bees
• Oklahoma agriculture
• pollination