Storing organic wheat is an important part of being able to market a quality product.  Since most organic wheat buyers cannot or will not take wheat at harvest, farmers must be able to store their wheat.  Of course, storage bins must be labeled as organic and harvest and storage records must be maintained to insure organic certification.  There is the potential for insects to become a problem in stored wheat. We recommend adding food-grade diatomaceous earth (DE) to the wheat grain as it is being loaded into the storage bins (at a rate of up to 40 pounds per 1000 pounds of grain). DE can be sprinkled on top of the grain while it is moving in the auger to the bin, and then on top of the grain after it is loaded. DE works because the surface of each particle is very sharp and these sharp edges cut into worms as they feed or move over the grain causing them to desiccate, or dry out and die. You can obtain food-grade DE from the following companies:

• Fertrell 717-367-1566
• Lancaster Ag Products; 717-293-9701

PyGanic © is another product that can be used alone or, for better control, in conjunction with DE in stored wheat and other grains.  It contains pyrethrum, is labeled for use in stored grains, and is listed by OMRI as compliant with the USDA Organic Program Dilute at the rate of 1 part to 22 parts water (6 fl. oz. with one gallon of water). Thoroughly mix the emulsion and apply at the rate of 5 gallons per 1,000 bushels of grain as it is carried along a belt or as it enters the auger or elevator. Pyrethrum does not have a long residual so inspect grain weekly during the warm summer months and monthly over the winter. If the top 2 or 3 inches are found to be infested, re-treat applying at the rate of 2 gallons of diluted material per 1,000 bushels of stored product. Bacillus thuringiensis (Bt) is recommended for the control of Indianmeal moths. Apply as a liquid or dust to the top 4 inches of grain. Use only products labeled for grain storage.Another approach is to use carbon dioxide as a fumigant. Carbon dioxide is listed as an allowed synthetic under 205.605b in the National Organic Program rules. Carbon dioxide concentrations must be elevated in the bin for 15 days to insure destruction of insects. Sealed or sealable bins are required. For a complete guide to using carbon dioxide, please see University of Minnesota's Store Grain Pesticide Manual.

Other resources

Insect Pests of Stored Small Grains in Small Grain Production Guide from NC State University

Management of Stored Grain and Peanut Pests from the University of Florida