More farmers are requesting performance data for reduced rates of corn rootworm insecticides. Many are concerned about reducing costs and lessening the impact on the environment and beneficial organisms. But before reduced rates are used, a very important question needs to be answered. Will a reduced rate provide the same root protection as the full labeled rate? To answer this question, ISU research entomologists conducted tests in Iowa during the last four years under a variety of environmental conditions, ranging from drought in 1988 to very wet soils in 1991. Tested products included Counter, Dyfonate, Force, Lorsban, and Thimet.