Wheat: 20-Point Checklist for Controlling Insects in Stored Grain

    Prior to Harvest

    [ ] Clean all equipment thoroughly to remove old grain, trash, and debris that might contaminate the new crop –

    • combines, carts, trucks, receiving pits/hoppers, conveyers: use pressurized air/water or an industrial wet/dry vacuum
    • storage bins: use a broom and shovel or industrial wet/dry vacuum

    [ ] Check for leaks in the bin around ladders, roof vents, temperature cables and other openings.

    [ ] Treat bin walls and flooring with an approved residual insecticide (currently approved compounds are Tempo, Centynal, Pyronyl and Insecto).

    [ ] Treat the outside base of all bins with an approved residual insecticide (Tempo).

    [ ] Mow, spray, or remove weeds/grass/vegetation around storage bins.

    [ ] Seal floor and fans, unloading augers or other openings with heavy plastic to prepare bin for fumigation.

    [ ] Treat area under perforated floors with approved products and application methods (diatomaceous earth (DE) and Phosphine)

    CAUTION: Fumigants are restricted-use, potentially lethal pesticides and require formal training for safe application.

    [ ] Post written notice that bin has been fumigated.

    [ ] Wait the required time before entering the bin–depends on product used and air temperature (Note: Safe re-entry times range from 2 to 3 days at 70°F and 4 to 5 days at 56°F).

    During Harvest

    [ ] If drying with heated air, limit drying temperature to 110°F or 140°F to preserve seed or milling quality, respectively.

    [ ] Dry wheat to 12.5 % moisture if it will be held through August. (Note: This keeps the air space between wheat kernels dry enough [less than 65% humidity) to control mold growth and insect activity. Moisture “shrink” costs 1.14 cents/bu-pt for each $1.00/bu value (12.5 cents/bu-pt @ $11/bu)]

    [ ] Apply approved insecticide on unheated wheat as it’s transferred into storage (It is best to use a DIFFERENT product than in Step 4, thus Centynal or Sensat is suggested).

    [ ] Apply a “cap-out” treatment to the wheat surface after the bin is full.

    [ ] Remove spilled grain around pits/hoppers and storage bins daily to prevent contamination.

    After Harvest

    [ ] Insert pit traps into stored grain and check them weekly during the summer to track insect activity.

    [ ] Check wheat temperature and moisture weekly after binning for stability.

    [ ] Core the bin within a month after binning to provide more uniform airflow.

    [ ] Move the grain to another bin before corn harvest to disrupt insect activity and potential hot spots.

    [ ] Cool wheat below 65⁰F as soon as possible when the weather permits in September.

    [ ] Continue cooling about 10 degrees each month to 35⁰F  to 40⁰F by December and seal fans.

    [ ] Fumigate wheat prior to sale if insect populations reach economic thresholds.

    CAUTION: Fumigants are restricted-use pesticides and require formal training for safe control.

    UPDATE: Chlorpyrifos was phaseout on Feb 28, 2022, so Reldan (chlorpyrifos) or Storcide (deltamethrin + chlorpyrifos) can no longer be used.

    The Latest

    Send press releases to

    View All Events

    [ecs-list-events limit="5" key="start date" order="asc"]
    Send press releases to

    View All Events