Excerpts from the report Summary: This report presents results of tests with various insecticidal dusts and sprays applied to stored wheat and shelled corn for protection from insect attack. The tests with synergized pyrethrum formulations made during the period September 1952 through December 1957 are summarized at this time, even though they are still in progress, because of the interest in protective dusts and sprays for the protection of stored grain. The studies were conducted on wheat and shelled corn stored on Commodity Credit Corporation, U. S. Department of Agriculture bin sites in rectangular, wooden bins of a rated capacity of 3, 200 bushels, and in standard circular metal bins of a rated capacity of 3,250 bushels. After the protective treatments were applied, the grain was sampled monthly to determine levels of insect population and moisture content, and quarterly for chemical residue analyses, bioassay tests, and commercial grade.