Use of grazing animals to control insect pests of pasture

Abstract

A review of the literature shows that increasing the stocking rate of domestic herbivores causes reductions in the populations of most pasture invertebrates (type I response), although populations of some species may reach a peak at intermediate stocking rates (type II response) or increase up to high stocking rates (type III response). The effects of defoliation and trampling on microclimate and the living space of pasture invertebrates probably account for most of these responses. Insect pests which show type I responses, e.g., porina Wiseana spp., Australian soldier fly Inopus rubriceps (Macquart) and grass grub Costelytra zealandica (White) are susceptible to control by increased grazing intensity and/or stock trampling at critical periods of the life cycle, but the use of grazing animals to control pests is constrained by such factors as weather, topography, restricted application time, and detrimental effects of hard grazing and trampling on animal and pasture production.

Keywords:

• cattle
• cultural control
• defoliation
• grazing
• pasture insects
• pasture pests
• sheep
• soil poaching
• New Zealand