Granary Weevil

Granary Weevil_Control_Header

This beetle has a polished chestnut brown or blackish body color that is approximately 5 mm long.  The characteristic feature of granary weevil is the long snout, however, it can be difficult to tell apart from the rice weevil.  The granary weevil feeds on grain kernels and leave only the shells.  The damage caused by the granary weevil often prepares the food stores for further insect infestation due to the increased number of damaged kernels. The adult beetles are unable to fly.  The typical lifespan is between 7 to 8 months. The female granary weevil drills a hole in a kernel to lay its eggs inside, which is subsequently sealed.  The female beetle will lay up to 150 eggs in the same number of grain kernels.  The granary weevil is very resilient to a wide range of temperatures, 15 to 30+ C.

How do granary weevils spread?

Like all weevils, granary weevils spread very easily.  The most common path of entrance into your home is through contaminated products, which include a variety of grains and cereals as well as dried fruits and nuts.  Food product contamination normally happens during food processing.  The risk of granary weevil infestation is much higher when foodstuff packaging is damaged when you pick it up off the shelf.  If you have a granary weevil infestation, it does not reflect the cleanliness of your home.  Weevils are also known to be very mobile.  If you are in an apartment building, there is a possibility that they could come from neighbouring apartments.

How can I identify granary weevils?

The rice weevil has a polished chestnut brown body that is approximately 5 mm long.  Weevil's have a characteristically long snout along with the ability to fly.  The granary weevil is commonly mistaken for a rice (or other species of) weevil. Rice weevils have four reddish patches on its rear body segment (elytra) whereas granary weevils are a solid chestnut brown. The damage that the granary weevil causes is similar to that of other weevils.  Larva will eat the endosperm within a kernel, whereas the adult will leave a significant exit hole in the kernel or feast on damaged kernels. Female granary weevils will lay their eggs in drilled out kernels. If you are having trouble identifying the beetle species, contact us for professional pest control service.

How do I control granary weevils?

As with all pantry pests, the first step in controlling them is to remove their sources of food from your pantry.  Seal suspected food sources in a plastic bag and keep an eye on them for up to a month.  If you notice any weevils in the sealed bags you should immediately discard the item. Since granary weevils mainly enter your home through contaminated food products, be careful to not purchase any damaged boxes or bags.  Controlling granary weevils can be difficult and a professional pest control expert is often necessary.  Call Nimby Pest Management today!