The potential to manipulate the numbers of insects in lucerne by strip cutting

Uncut strips of lucerne (Medicago sativa L.) were evaluated as refuges for natural enemies of pests in lucerne hay crops. Vacuum catches of seven spec ies of predator were significantly greater in uncut strips than in cut cont rol areas on as many as six of seven sample dates over three harvests. Catc hes of pest larvae (Helicoverpa spp.) (Lepidoptera: Noctuidae) were consist ently lower in the natural enemy refuges than in regrowth 16 or more days a fter harvest. Further work with larger plot sizes is warranted.