Lesser Grain Borer Beetle
Lesser Grain Borer beetles are black or brown, stout insects that have a body length of about 1/2 inch. They feed on dried plant products that contain grain, cereal, wheat, corn, rice, oats and other seeds. These can include food items made with flour such as pasta dough and bread dough. They are also found in cereal boxes, flour sacks, and other places where food is stored. Lesser Grain Borer beetles can be found on the surface of grain bins or in silos containing grains. The females burrow into grain kernels to lay their eggs while the larvae feed on the interior of kernel and can damage it severely.
Lesser Grain Borer Beetle
Lesser Grain Borer Beetle Facts
The first sign of a problem can be small piles of beetle feces on the surface of grains or in flour sacks. This is where the beetles gather to lay their eggs and is often described as looking like pepper or black sand. Beetles and larvae are also sometimes found trapped in spider webs when they crawl up walls or window sills in search for light sources to help them navigate.
People sometimes mistake Lesser Grain Borer beetles for Rice Weevils. It can be easily mistaken for the Rice Weevil because it has the same long snout and considerable size. The easiest method to tell rice weevil from a grain borer is that grain borers have three light brown lines on their back toward the head area. Rice weevils do not have those lines.
Behavior of Lesser Grain Borer Beetle
The adult beetles are generally most active at night, especially during warm humid weather. They are known to fly to lights and are attracted by the yellow light given off by common porch lights. The adults live for about a month if food is abundant and they will eat all of their nutritional needs but can survive on fat reserves as long as no food is available. When food is scarce, such as in the winter months, many adults enter a state of hibernation until warmer temperatures arrive.
Grain Borer Prevention
The key to preventing an infestation of Grain Boring Beetles is to keep food sources completely sealed and stored in the refrigerator if they cannot be used immediately. Removing infested foods such as old cereals, damaged food items and those with broken packaging will reduce chances for beetles gaining access. These pests are known to invade other food items such as dried flower arrangements, empty bottles, and jars that may be left on shelves or in cupboards.


Contact Us
If you find any Grain Boring Beetles in your Charlotte County home, contact Bug Off Pest Charlotte immediately. We can help rid you of these garden pests and get your lawn or yard back to normal! As always, we are happy to answer any questions you may have about Grain Boring Beetles or any other pest. Call us today 941-676-2005