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Grain Weevil

How To Deal With A Grain Weevil Infestation

The grain weevil, also commonly referred to as the wheat weevil, is quite a little pest.  As disgusting as it sounds, it is very likely that you have eaten them and their eggs.  Most people are not aware of this information and you probably have not eaten an adult but rather their larvae, exoskeleton or even a shed leg.  Unless you don’t eat any prepackaged food with grain such as pasta, crackers, cookies, cereal, etc., they are pretty difficult to avoid.

Appearing quite similar to a very small beetle, the grain weevil usually matures at a size of less than one-quarter inch.  The female uses her snout to literally drill holes in grain casings such as wheat, rye, oats, rice, barley, corn, beans and seeds.  After this is done, she deposits her egg and then seals up the hole with a substance that is glue-like and created by her.  After a few days, the egg hatches and the larvae feeds on its surroundings for about a month, unless it is eaten first.  What’s more disturbing than this?  A female is capable of laying 400 eggs so an infestation is a serious matter.  If you think that you have a female grain weevil reproducing in your pantry, it is important that you know how to tackle this issue.

Remove Contaminated Food

Anything in your pantry that you even think may be contaminated needs to be thrown away.  If you are like most people, you probably hate the thought of throwing away food but unfortunately, this has to happen.  Keep in mind that if you keep something that you think is questionable, your future food that you buy could become infested.  Throwing the items away now will save you money in the future.  Make sure that you dispose of everything in the outside garbage far away from your kitchen.

Clean Your Pantry

Your cupboards and pantry need to be thoroughly cleaned.  Remove everything from the shelves and vacuum every single crack and corner.  If your shelves happen to have contact paper, get rid of it.  After it is all vacuumed out, use hot soapy water and wipe everything down really good.  Once this is done, get fresh water and a clean towel and do it again.  Immediately put the towels you used in the washing machine.


To avoid another female grain weevil from coming in and laying eggs again, everything should be stored in tight-lidded containers made of glass, plastic, steel or tin.  You need to also get in the habit of cleaning your pantry out regularly.  This will also give you a good opportunity to make sure that everything is rotated.  It is also advised to caulk any cracks as well to reduce the chance of anything getting in.


It may sound strange but a grain weevil will not go near a book of matches.  The sulfur smell is an excellent deterrent so lay a few books of open matches on the shelves that house your grain products.


While you cannot allow matches to actually sit on your food, cloves are perfectly safe.  Before putting your grain products in your pantry, throw a clove in with them.  You can even scatter these around the shelves just to be on the safe side.

Cold And Hot

Freezing your food eliminates the chance of a grain weevil infestation.  You can pretty much freeze everything including bread, oats, flour, cookies, etc.  Weevils cannot survive freezing temperatures or if you have food that you think may be questionable and you don’t want to throw it away, you can put it in the freezer to kill eggs, larvae and adults.

A little heat will also realize the same goal if you do not have room in your freezer.  Preheat your oven to only 120 degrees Fahrenheit.  Lay everything on a baking sheet and cook for an hour.  After removing, be sure to put the food in seal tight containers.