Growers incorporating on-farm storage into their grain production, management, and marketing programs, need to be aware of the long-term consequences of pest damage in stored grain, says Jason Ward, Mississippi State University Extension associate agricultural engineer.
“Integrated pest management needs to be a part of every decision you make during the year,” he said at a recent stored grain management workshop.
“Borers and moths are your key enemies,” he says. Careful attention to sanitation, bin wall treatments, sealing of bins, treating grain as it goes into the bin, topdressing, and monitoring are all components of a pest management program, he notes.
“Be sure to rotate chemistries to reduce chances for resistance — we’re already seeing quite a bit of resistance to malathion.”
Bin wall treatments (Tempo, Storecide, malathion, methoprene) should be done four to six weeks before putting corn in bins, Ward says. “Spray material on the walls to the point of runoff.”
Also for insect control, diatomaceous earth, which is composed of hardshell microorganisms, could be used under plenum floors to reduce the cleanout frequency, he says.
Moisture is also an enemy of stored corn, so be sure to seal bins properly, he advises. “This is also important if you should need to fumigate; you need a tightly sealed bin in order to get a lethal level of fumigant. If you need to fumigate, we think it’s best to let professionals do it for you.”
Crop treatment/top-dressing employs chemistry similar to that for bin treatments, Ward says. Apply at the auger and mix into the last truckload going into the bin.
To monitor grain condition, take samples with a probe. Use pheromone strips and insect collectors to monitor infestations.
With the big movement to corn in recent years, a lot of producers didn’t have enough equipment to adequately handle grain being brought in from the field, he says, which generated a lot of interest in on-ground piles, silage bunks, grain bags, etc.
“For identity preserved grain, if the end user wants a specific type of grain separated out, or is paying a premium for certain grain, or if you want to segregate poor quality grain, alternate storage may be an answer,” Ward says.
“In the Midwest, a lot of grain goes directly into storage bags, which facilitates harvesting, but in our southern environment, a lot of work remains to be done with these systems.
“Site location for these bags is extremely important. Avoid low-lying areas, and have as smooth, firm a surface as possible. Think of it as you would a cotton module — that it needs care in filling, and systematic attention while grain is in the bag.”
For pest management, Ward says, keep weeds away from bags, use mothballs to minimize rodents, don’t use elemental sulfur near bags, and don’t leave grain on the ground to attract pests.
“When unloading grain, don’t go into the bag — there is a potential suffocation hazard. If you cut an opening in a bag, be careful to do it so you avoid spilling grain on the ground, and start cutting with round holes.”
If planning to use storage bags, Ward says, “Be sure you’ve got the needed equipment and correct horsepower, hydraulic capacity, PTO, transport, etc.” Prices can run $40,000 to $60,000 for a typical system, plus the cost of the bags.
He says research is continuing with storage bags “to try and get more answers for their use under our environmental conditions.”
If temporarily storing corn on the ground in covered piles, Ward says, “Be aware that moisture is a major enemy of corn.” He advises crowning the center of the pile to facilitate damage and orienting piles north/south in order to get the most advantage from solar drying.