Grain storage is a component of grain marketing, especially in years of low prices at harvest and/or volatile market conditions. Looking to the 2018 corn and soybean grain harvest, growers need to make preparations for storage of these crops. That preparation should include a thorough cleaning of combines and grain carts, consolidating any 2017-grain crops in storage to free up empty space for 2018 grain, and preparing grain bins for 2018 crop. In this article, I am drawing on the expertise and recommendations in previously written articles by Curtis Young, Extension Educator in Van Wert County with regard to new crop storage preparation.
Step 1: Remove all traces of old grain from combines, combine heads, truck beds, grain carts, augers, lift buckets, grain pits, grain driers, bins and any other equipment used for harvesting, transporting, and handling grain. Even small amounts of moldy and/or insect-infested grain left in equipment can contaminate a bin of new grain.
Step 2: Consolidate or market any 2017-grain crops to make bin space for the 2018 crop. The guiding principle here is that new grain should never be stored on top of grain from a previous harvest season. That is a formula to develop storage problems, either from insects, mold or both.
Step 3: Prepare grain bins for storage of the 2018 crop. Quoting from Curtis Young here: “Remove any grain or grain dust from inside the bins by sweeping or vacuuming empty bins and brushing down walls. Pay close attention to cracks and crevices, ledges over doors, and hollow tube ladder rungs where grain residue can accumulate. Clean fans, aeration ducts, exhausts, and even the area beneath slotted floors.
Sanitation outside of bins is as important as inside of the bins. Ideally there should be no vegetation (weeds, shrubs, etc.) growing up against the outside of the bin. Vegetation can harbor grain pests (insects and rodents). Bare ground covered with gravel or cement is preferred, but short-mown grass is tolerable. Remove any spilled grain from around the outside of the bin and storage facility.
Inspect bins for signs of deterioration, especially for leaks and holes through which insects, birds or rodents can gain easy access to the stored grain or moisture can drip or blow in onto the grain to produce wet spots that can lead to mold growth. While inspecting for physical problems, test aeration fans and driers for functionality. Check belts, bearings and gear boxes for wear and proper lubrication. Check electrical systems for corroded connections and frayed wiring before harvest. Mice like to nest inside electrical boxes. They will strip insulation from wires for nesting material and their urine causes corrosion. Be sure to seal any openings through which mice could get in. Be sure that guards and safety shields are in place over belts, chains and intakes.
After all cleaning and repairs have been completed, an empty-bin application of an appropriately labeled insecticide is advisable, especially in bins with difficult to clean areas and/or in bins with a history of insect problems. For empty-bin insecticide treatments that are applied as a liquid, allow a minimum of 24 hours for the sprays to dry before loading grain into the bin. It is preferable to have empty-bin treatments applied at least two weeks prior to harvest.”
According to 2018 Insecticide Recommendations University of Kentucky Extension publications Ent-13 and Ent-16, registered empty bin insecticides for soybeans include Tempo SC Ultra (cyfluthrin), Diacon-D IGR (s-methoprene = an insect growth regulator), and products that contain diatomaceous earth and/or silicon dioxide such as Insecto, Protect-It, and Perma-Guard. Empty bin surface insecticides for corn include all of the products registered for soybeans plus Centynal (deltamethrin) and Pyronyl (pyrethrin).
In situations where grain infesting insects have been observed on the outside of bin walls, an application of a perimeter spray around the base of, and up approximately 15 feet on the outside walls of the bin is useful. There are several synthetic pyrethroids (cyfluthrin, deltamethrin, permethrin, resmethrin, etc.) labeled for this purpose. Take care that these products do not contact the grain.
Insecticide labels for grain storage products tend to change frequently. Make sure to read and follow label directions and that you are using the appropriate product for your situation. From a marketing perspective, make sure that the end-user of the stored grain does not have restrictions on insecticide uses on or around the grains that they are going to purchase. For any specialty grains, check with buyers and their requirements before using insecticides.