How to Get Rid of Weevils

Quick answer: To get rid of weevils, throw out infested grain products, then vacuum and wipe pantry shelves with soap or vinegar water. Store flour, rice and cereal in airtight containers, and freeze new packages for several days before storing them.

Weevils are small beetles with long snouts, and some of them are among the most troublesome pests in kitchens, gardens and farms. Some eat stored foods like rice and flour, while others chew garden plants, crops and trees. The good news is that most weevil problems can be fixed without strong chemicals.

Weevils Quick Facts

Common name	Weevils
Scientific name	Curculionidae
Kingdom	Animalia
Phylum	Arthropoda
Class	Insecta
Order	Coleoptera
Type	Insect (beetle)
Diet	Plants, seeds and stored grains, depending on the species
Habitat	Pantries, grain stores, gardens, farms and forests
Native range	Worldwide
Size	Most pest weevils about 2-10 mm long
Special feature	Long snout with jaws at the tip

What are weevils?

True weevils belong to the beetle family Curculionidae, one of the largest animal families on Earth, with tens of thousands of species. Thousands live in North America alone. Most weevils have a long snout, called a rostrum, with tiny chewing jaws at the tip and elbowed antennae on the sides.

A few pests called weevils, such as bean and cowpea weevils, are actually seed beetles from a different family, but they cause similar problems.

Common pest weevils

Different weevils cause different problems, so it helps to know which one you have. Here are some of the most common:

Boll weevil

The boll weevil (Anthonomus grandis) is about 6 mm long and grayish-brown. It lays its eggs in cotton buds and young cotton bolls, and its larvae eat them from the inside. It was once one of the most destructive farm pests in the United States, but large eradication programs have removed it from most US cotton-growing areas.

Flour weevil

The name flour weevil is a nickname for the small beetles people find in flour and other pantry foods. Often these are grain weevils, which breed in whole grains, or reddish-brown flour beetles, which are not true weevils at all. Both are only about 3 to 4 mm long.

Rice weevil

Rice weevil – Photo by: Olaf Leillinger

The rice weevil (Sitophilus oryzae) is a serious pest of stored rice, wheat, corn and other grains. It is only about 2 to 3 mm long, with a long snout and a dark brown body marked with four reddish or orange spots on its wing covers.

Bean weevil

Bean Weevil – Photo by: Clemson University – © Bugwood.org

Bean weevils are seed beetles in the subfamily Bruchinae, part of the leaf beetle family. They are not true weevils and do not have long snouts. Most are only a few millimeters long and brown, gray or black. Their larvae grow up inside dried beans and peas, often spending their whole larval life inside a single seed.

Wheat weevil

Wheat Weevil – Photo by: CSIRO

The wheat weevil, more often called the granary weevil (Sitophilus granarius), feeds on whole grains such as wheat, barley, oats, rye, rice and corn. It is about 3 to 5 mm long, shiny dark brown to black, and cannot fly.

Black vine weevil

Black Vine Weevil – Photo by Denny Bruck.

The black vine weevil (Otiorhynchus sulcatus) is a garden pest about 1 cm long. It is black with tiny patches of yellowish hairs. Adults notch the edges of leaves on plants like rhododendrons, while the grubs eat roots, which can kill potted plants. Almost all black vine weevils are female, and they cannot fly.

Rose weevil

Rose Weevil – Photo by: Ingrid Taylar

The rose weevil, or rose curculio (Merhynchites bicolor), is red and black and about 5 to 6 mm long. It drills holes into rose buds with its snout, so the flowers are damaged or fail to open.

White pine weevil

Pine Weevil – – Photo by: Arnstein Rønning.

The white pine weevil (Pissodes strobi) is about 4 to 6 mm long, rusty brown with patches of white and tan scales. Its larvae tunnel into the top shoot of white pines and spruces, killing it and leaving the tree crooked.

Cowpea weevil

Cowpea Weevil – Photo by: Carl Davies, CSIRO.

The cowpea weevil (Callosobruchus maculatus) is a seed beetle that infests stored cowpeas (black-eyed peas) and other beans. It is reddish-brown with darker and lighter patches on its wing covers.

How weevils get into your home

Most pantry weevils arrive in food you bring home. Rice, flour, grains, pasta, nuts, dried beans, cereals, popcorn kernels and birdseed can all carry eggs or larvae. Once inside, the weevils spread to other foods in the cupboard.

Some plant-feeding weevils wander indoors from outside, especially in autumn, looking for shelter. They crawl in through gaps around doors and windows, cracks in walls and vents. These weevils do not usually breed or eat food indoors. They are simply lost visitors and can be swept up or vacuumed.

Getting rid of pantry weevils

• Find the source: Check every package of grain, flour, pasta, cereal, nuts, dried beans and pet food. Throw away anything with live weevils or tiny holes in the grains.
• Clean the cupboard: Take everything out, vacuum every crack and corner, then wipe the shelves with soap and water. Empty the vacuum outside.
• Freeze new food: Putting new packages of flour, rice or grains in the freezer for about four days kills any hidden eggs or larvae.
• Use airtight containers: Store dry foods in sealed glass, metal or thick plastic containers so weevils cannot get in or out.
• Buy smaller amounts and use older food first, so nothing sits in the cupboard for months.

Insect sprays should never be used on food or in food cupboards to treat weevils. Cleaning, freezing and good storage work much better.

Controlling garden and farm weevils

• Hand-pick: Many garden weevils feed at night. Check plants with a flashlight after dark and shake the weevils onto a sheet or into soapy water.
• Beneficial nematodes: These microscopic worms can be watered into the soil or pots to kill vine weevil grubs.
• Remove damaged buds and shoots: Cut off and destroy rose buds or pine shoots with weevil damage to stop the larvae inside from finishing their growth.
• Use barriers: Sticky bands around pots or stems can stop flightless weevils from climbing up.

Traps

Farmers, warehouses and food factories use traps baited with pheromones, scents that copy the signals weevils use to find each other. The traps show how many weevils are around and help people decide whether they need to take action. Pheromone traps were an important part of the program that eliminated the boll weevil from most US cotton fields. There are also traps for pantry pests that can be used in homes, mainly to check whether weevils are still around.

For a large outdoor infestation, an adult can ask a local garden center or agricultural extension office for advice on the safest treatment.

Related: What Do Beetles Eat?

Weevils FAQs