Tips for preventing insect infestation during fall grain storage

Proper preparation and care before and after you store your grain can prevent insect infestations. Here’s how:

Decide which bin you will use for each crop

  • How you clean and prepare an empty bin depends on what type of crop you plan to store in it.
  • Avoid using chemical insecticides, for example, malathion, on bins in which you plan to store canola or flax. These oilseed crops absorb malathion and the residue remains in the seed.
  • When you plan to store cereal grains, there are several approved insecticides you can use to treat the interiors of empty grain bins.

Clean your bin thoroughly before harvest.

  • Insects in grain bins feed on debris, dockage and leftover cereal grain.
  • Clean the bin with high-pressure water or air, a heavy broom and/or a vacuum. Don’t forget to clean aeration systems.

When you add clean grain to the bin ensure the surface is level.

  • Aeration is more effective when the grain pile is level.
  • Grain is a very good insulator. If warm grain is stored and left undisturbed, convection currents can develop and cause hot spots and condensation.

Bring the temperature of the grain down to 18°C as soon as possible.

  • If you lower moisture content below 14.5 % and cool the grain below 18°C you can prevent stored-grain insect pest problems.
  • Most stored product pests do not feed or reproduce below 18ºC.
  • Grain bulks that are stored above 14.5 % moisture content can develop heated regions.
  • Heat encourages fungal growth. Fungi and heat attract insects to stored grain.

Monitor the temperature of stored grain and aerate the grain bulk.

  • Check the temperature of the bin every 2 weeks. Aerate stored grain as soon as possible after harvest particularly if aeration can reduce the bulk temperature below 18°C.
  • When the ambient temperature falls below that of the grain bulk (during the early evening, night and early morning), you can use aeration to reduce the temperature of the grain.
  • Aeration systems preserve stored grain and keep it dry by reducing the temperature of the grain and reducing moisture migration.
  • Always ensure that temperature fronts have moved fully through the grain bulk prior to stopping the aeration.

If you need to temporarily store grain temporarily, give consideration to:

  • If grain is stored on the ground, ensure the ground is hard and the site is convex.
  • Determine if there’s a need to manage grain temperature/moisture in temporary storage and how it will be accomplished.
  • If grain is stored on the ground, cover the grain as best possible.
  • If silo bags are used, regularly check and maintain the integrity of the bag.
  • Move temporarily stored grain into bins as soon as possible.