Signs of Insect Infestation in Grain Storage Bins

Post-harvest insect damage to stored grains is estimated to cost the U.S. agricultural industry upwards of $2.5 billion a year. Proactive prevention of stored grain insects includes the implementation of an Integrated Pest Management (IPM) program and the proper application of stored grain insect control products such as Diacon® IGR PLUS.

If you find signs of grain bugs, it is important to ensure proper grain insect idenfication to confirm which insects are present and determine the most effective means of stored grain insect control. Dust, odor and damaged grain are all indicators of an insect infestation.

Common Signs of Grain Insects:

Shot hole appearance in kernels

The rice weevil leaves holes in grain and deposits larvae inside of kernels.

Dense insect webbing on equipment or grain

Indian meal moth larvae weave dense webbing on the top 4 to 6 inches of grain and other surfaces. Indian meal moths are also spotted by the presence of adults flying near the grain or larvae climbing nearby walls.

Elevated grain temperature

Sawtoothed grain beetle activity causes grain temperatures to increase and overheat, typically resulting in a visible population build up.

Sweet, musty grain odor

The lesser grain borer is known to leave behind dust and just the outer husk, totally consuming the internal kernel. They also can have a sweet, musty scent.

Get Professional Stored Grain Insect Control

If insects are detected, it is best to turn the grain and treat it with a tank mix of Diacon® IGR and Centynal EC Insecticide or the combination product Diacon® IGR PLUS. If you suspect weevils are present, it is important to incorporate PBO-8® Synergist, as it boosts the active ingredients in Centynal EC Insecticide and Diacon® IGR PLUS, significantly improving the effectiveness against this difficult-to-control insect. For severe insect infestations, consider treating with an EPA-registered fumigant.

For the most effective control of stored grain insects in the future, you’ll need to get ahead of infestations with proper prevention. This includes cleaning empty bins, treating empty bins and applying grain protectants to the newly harvested grains as they go into the cleaned bins.


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