Badly infested grain may require fumigation (release of poisonous gas into the stored grain mass). Fumigation of large-volume storage facilities is a specialized and potentially hazardous procedure. Contact local experts for guidance and materials.

Grain fumigants

  • aluminum phosphide (PH3 Alp Fumigant Tablets and others)—The tablet or pellet formulations are most suitable for farm applications; consult label for directions.
    • Solid aluminum phosphide formulations release hydrogen phosphide (phosphine) gas when exposed to moisture and heat. Warm, humid air accelerates the reaction while cool, dry air slows it down. The reaction starts slowly, gradually accelerates, and then tapers off.
    • Aluminum phosphide tablets and pellets may be applied to the grain mass by probing them below the grain surface, adding them as the grain is turned, or placing them in the aeration ducts below the grain mass. Treatment while turning the grain generally is not feasible in on-farm storage, and often alternative methods must be used to treat the grain in place.
    • In shallow bins, tablets may be probed into the grain using a 5- to 7-foot-long hollow tube, designed for this purpose. These tubes can be purchased or made from electrical conduit or plastic pipe, according to distributor recommendations.
    • Sealing the bin is the single most important step in fumigation. Properly sealing grain bins before fumigation is essential for reaching and maintaining the required combination of gas concentration and exposure time necessary to kill grain pests.
    • Phosphine gas is also available in a pressurized container; consult label for directions.
    • magnesium phosphide (Degesch Fumi-Cell)—Similar to aluminum phosphide, though the more rapid release of phosphine may hinder penetration as well as endanger the applicator. This product must have a Fumigation Management Plan (FMP) in place prior to use. Consult label for directions.
    • methyl bromide (Methyl Bromide 100 Commodity Fumigant and others)—Do not use this product when the temperature is below 40°F. This product converts into a gas at temperatures above 39°F and has virtually no odor or irritating qualities to indicate its presence. Consult label for necessary PPE and work time restrictions when using this product.
    • sulfuryl fluoride (ProFume) applied by trained staff for seeds of any commodities.