Whenever I open my grain store, small moths fly out and I see webbing and clumped grain on top. What is this and how do I clean it up?
2 Answers
Those flying insects are storage moths, commonly the rice moth or the Indian meal moth. The adults do not eat grain, but their caterpillars do, and the webbing and clumped, matted grain on the surface is the giveaway. They mainly attack the top layer and broken or floury material. To control them, first scoop off and discard the webbed, clumped top layer where most larvae and cocoons hide. Spread the rest in the sun to drive out and kill stages, and sieve out dust and broken grain. Clean the bin walls, lid and corners because moths pupate in cracks and along seams. Then store the cleaned, dried grain in an airtight container filled to the top. Because moths need to fly and mate, sealed storage breaks their cycle well. Keep the store dark, dry and clean, and remove any spilled grain nearby that keeps them breeding. Avoid chemical sprays on stored food grain; any fumigant is hazardous and restricted and must be handled only by a trained or authorised person. Confirm safe storage moisture for your grain with your local agriculture office.
The webbing was always on top for me too. Removing that crust and sealing the drum stopped the moths within a month.