Keith Waldron, NYS IPM
Planning to store wheat on the farm? Are your grain bins ready? Wheat harvest is still a while off but it is not too early to begin thinking about gearing up for the big event. To maintain the profits a good yield can bring, make and follow a plan to protect your grain while it is in storage. Remember: Grain storage will not improve grain quality. However, proper management of grain during storage will protect the quality present at harvest.
The IPM approach for stored grain protection includes a combination of sanitation, well-sealed bins, frequent monitoring for temperature and insect populations, aeration to cool grain in the fall, and pest management treatments as needed. Stored grain management begins with “an ounce of prevention”. This article will highlight some steps one can take now to protect stored grain before it is harvested. The following pre-harvest information was “gleaned” whole or in part from Stored Grain IPM information from Oklahoma State University Stored Products Research & Education Center and Purdue University. Website source URL’s are provided at end of this article.
Insect infestations are the more common stored grain pest issues one might encounter. Insect infested grain can be docked at time of sale. Most common grain bin insect problems can be traced back to infestations in previously stored material, cracked grain and grain fines and trash. Don’t add new grain into storage bins that have not been cleaned and may harbor a collection of stored grain pests. The key to prevention is SANITATION – clean out the bin every time it is emptied. How clean? If you can tell what was stored in the bin the last time it was used, it needs more cleaning. In addition to insects, birds and rodents are also attracted to left over and spilled grain. Lights mounted on or in close proximity to grain bins may attract unwanted stored grain insects.
Who might the likely insect pests be? A variety of beetles, weevils and moths are common to stored grain infestations. Saw-toothed grain beetles, flat grain beetle, red flour beetles, granary weevils, Indian meal moths and Angoumois grain moths to name a few. A picture is worth a thousand words and the following extension factsheets provide information to help identify the insects you may find as you clean out your storage bins: Principal Stored Grain Insect Pests of Indiana, Stored Wheat Insects identification key (http://bru.gmprc.ksu.edu/proj/sga/key.asp) and Stored grain pests identification (http://storedgrain.com.au/wp-content/uploads/2013/05/Stored-grain-pests_NorthSouthWest_Pocketguide.pdf).
To prepare for grain harvest and storage the following sanitation practices are recommended.
* Clean harvest and transportation machines before harvest.
* Repair all grain handling equipment before harvest and keep it in good condition.
* Seal unloading auger, auger tube opening, and side door openings before harvest
* Empty storage structures of old grain. The new crop should never be stored on top of old grain.
* Remove and destroy any grain from beneath, around or near the bin area. Sweep and vacuum the floors, false floors, and walls inside empty bins to remove old grain and debris. This debris usually contains insect eggs, larvae, pupae, and/or adults, all ready to infest the new grain. A shop vacuum, broom and scoop are very useful in a cleanup job, and all collected material should be discarded properly.
* Check fan boxes for possible grain pests.
* Remove any spilled grain outside the storage structure.
* Mow / remove weeds at least 10 feet around the bins.
* Check and clean or replace rodent traps / bait stations. Be sure to follow all label directions.
* Check the integrity of screens and porcupine wires to limit bird entry and roosting.
* Insecticides? For additional protection against infestation, the inside and outside surfaces, foundations and floor of a storage facility can be sprayed with residual insecticide, four to six weeks prior to harvest, to kill any insects that were not removed during cleaning and those that migrate into the bin. Use appropriately registered insecticides. Be sure to follow all label directions. Rotate choice of insecticide chemical families to minimize risk of developing insecticide resistance.
* Establish a written sanitation schedule. Keep appropriate records.
Bin Sealing
Roof leaks commonly lead to columns of spoiled grain. Check for these leaks by looking for light coming into the bin. Moisture coming into the bin through the seal between the bin and concrete will cause spoilage around the perimeter of the bin at the base. Check the seal since sealants do deteriorate. Water will run away from the seal at the base of the bin wall if the concrete is sloped away from the bin. Also check the seals around the doors and hatches.
Besides keeping grain dry, grain storages should be well sealed for two other basic reasons: (1) to minimize grain insect entry problems into base and sidewall grain, and
(2) to minimize leakage should fumigants be used.
In addition, improved insect kill (efficacy), tighter sealed structures require lower dosage rates, which reduce the cost of future fumigations and cover the cost for the sealing materials and labor. When clean grain is transferred into a clean, sanitized structure with base and sidewalls well sealed, the main insect infestation and population growth should be on the grain surface in the structure headspace. Permanently sealing all non-functional base, sidewall and roof openings is the first priority of sealing storages. The second sealing priority is to seal functional openings at all times during the year when the component is not being used.
Source of the above stored grain pest management information:
Purdue’s Stored Product Pest factsheets:
Two excellent Stored Grain IPM resources:
“Stored Product Protection” – Practical guide to protecting grains and other raw commodities, food processing facilities, finished food, and durable plant and animal products from insects, molds, and vertebrate pests. Illustrated, 350 p. (http://www.ksre.ksu.edu/bookstore/pubs/S156.pdf)
“Maintaining Quality in On-Farm Stored Grain” https://utextension.tennessee.edu/publications/documents/PB1724.pdf