Excerpts from the report Preface: This report presents results of a small-bin, intermediate-type experiment with wheat treated with the standard malathion protectant application, a candidate chemically active insecticidal material (diazinon), a silica aerogel (Cab-O-Sil), and a diatomaceous earth (Kenite 2-1) for protection against the lesser grain borer. Materials and dosages treated were selected on the basis of previous laboratory and small-bin studies. The two experimental protectant materials—diazinon and Cab-O-Sil—have not been registered with the Pesticides Regulation Division, Agricultural Research Service, as grain storage treatments, and residue tolerances have not been established by the Food and Drug Administration for Cab-O-Sil or diazinon. All diatomaceous earth products containing more than 80 percent silicon dioxide are exempt from the requirements of a tolerance for use on certain stored grains including wheat. Trade names or proprietary names are used in this publication solely to provide specific information. Mention of a trade name or testing of a material does not constitute a guarantee or warranty of the product by the U.S. Department of Agriculture and does not imply either a recommendation for its use or an endorsement over comparable products.