By Clint Schroeder, OSU Extension, Allen County
The 2020 Ohio wheat harvest is rapidly approaching. Now is the time to prepare for a successful harvest. Before the combine goes to the field, a key component will be to have grain handling and storage facilities adequately sanitized. Taking the proper steps now should help eliminate insect infestations that can significantly reduce grain quality or salability.
The majority of insect infestations that occur in stored grains are a result of migration into the bin. These insect populations will be present in piles of spilled grain from the previous year, livestock feed in the area, litter, and weed growth. Newly harvested wheat can also be contaminated when it comes in contact with infested grain that was not cleaned from the combine, trucks, wagons, augers, dump pits, or grain leg buckets. Another source of contamination can be carryover grain in a bin that was not correctly emptied.
Proper sanitation begins outside the bin. Brush/sweep or vacuum out any grain left in the combine, wagons, or grain carts. Remove all vegetation that grows within ten feet of the bins. Then spray this area with a residual herbicide to prevent regrowth. Remove any grain spills or other debris that might have accumulated during the load out of the previous crop. This step will minimize the habitat available and make migration to the bin more challenging.
Inside the bin, it is crucial to make sure that there was no grain left from the previous crop. Thoroughly sweep or vacuum any area that grain could potentially be sitting on, which includes any ledges, ladders, or braces. Remove all dust and debris from fans, aeration ducts, and under slotted floors (when possible). Insects may remain in these hard to clean areas. While the bin is empty, an insecticide application should be completed to combat this potential problem. The treatment will help create another barrier for insects that try to migrate into the bin, but should not be used as a replacement for proper sanitation. The best time to apply insecticides to empty bins is two to three weeks before harvest. Some of the products that can be used for this application are Diacon II (s-methoprene), Storcide II (deltamethrin and chlorpyrifos-methyl (3 ppm)), Tempo 20WP (cyfluthrin), Tempo SC Ultra (cyfluthrin) or diatomaceous earth products. These products can also be applied to the external walls of the bin to create a secondary barrier. It is critical to read the full product label and follow all label instructions.