How does a weevil protect itself

Rice weevils are capable of flight, and infestations may develop in the field prior to harvest. Maize weevils, for a long time were referred to as a larger strain or race of the rice weevil, but are now recognized as a distinct species. The maize weevil is slightly larger, up to one-eighth inch four mm long, and darker than the rice weevil; the degree of variation within each species makes them difficult to tell apart. The thorax of the maize weevil is densely and uniformly pitted with round punctures.

An egg hatches in a few days into a soft, white, legless, fleshy grub which feeds on the interior of the grain kernel. After the larval stages are completed the grub changes to a white pupa and later emerges as an adult beetle. Adult granary weevil live an average of about seven to eight weeks. Each female lays 50 to white eggs during this period. The female uses her strong mandibles to chew a small hole in the grain kernel, where she deposits a single egg in the hole and seals it with a gelatinous fluid.

In warm weather, the granary weevil can develop from egg to adult in about five weeks. Cold weather prolongs development. The granary weevil cannot fly and so is most likely to be found where grain is stored, and moves with infested grain.

These weevils are very destructive grain pests. Of the three, the rice weevil is probably the most insidious, owing largely to the ability of flight. All three weevils develop as larvae within the grain kernels.

They frequently cause almost complete destruction of grain in elevators or bins, where conditions are favorable and the grain is undisturbed for some length of time.

Infested grain will usually be found heating at the surface, and it may be damp, sometimes to such an extent that sprouting occurs.

Wheat, corn, macaroni, oats, barley, sorghum, Kaffir seed, and buckwheat are just some of the grains and products on which these weevils feed. Prevention is the best strategy to avoid insect problems in stored grains. Proper bin sanitation before introduction of new grain minimizes the need for pesticides. Good sanitation involves the removal of old grain and dust in and around the grain bin.

This includes removal of old grain from corners, floors, and walls and grain that may have spilled on the exterior of the bin. Homeowners might not notice weevils when they are gathered on the outside of the home. But if the weevils manage to find an opening and invade the home, the homeowner often finds hundreds of insects crawling on the walls and windowsills. Size: Many are slender or oval-shaped insects. Depending on the species, weevils range in size from about 3 mm to over 10 mm in length.

Head: The most distinctive feature of weevils is the shape of their head. An adult weevil has an elongated head that forms a snout. The mouth is at the end of the snout. Some weevils have a snout that is as long as the body. Another family of beetles called. Bruchidae , such as the cowpea weevil, have a different appearance from the typical weevil.

They lack the elongated snout found in the. Weevils feed on plants in the larval stage and as adults. Some can be very destructive to crops.

For many years, one of the most destructive weevils was the cotton boll weevil. The black vine weevil , Otiorhychus sulcatus F. It feeds on a variety of plants, including hemlocks and rhododendrons. Weevil life cycles depend greatly on the species. For some, in spring, adults lay their eggs on the ground near host plants. When the eggs hatch, the larvae burrow into the ground and feed on the roots. Since the larvae are underground, people seldom see them.

Many of the larvae spend the winter in the ground and emerge as adults the following spring. However, the adults that emerge during the summer or fall may invade homes for shelter. Some, like the Asiatic oak weevil, are attracted to light, so they are drawn to homes at night. Others may be attracted by the warmth from the house. Boll Weevil —The boll weevil Anthonomus grandis is a type of beetle that is known to cause severe damage to cotton crops. Getting rid of pantry weevils is difficult but not impossible.

Prior to calling an exterminator, there are several steps you can take to try to remove these pests from your pantry. To fully remove the pantry weevils and prevent a future infestation, remove all unsealed dry foods from your pantry shelves.

This includes opened containers of rice, flour, pasta, and cereal, as well as boxed foods that are not sealed internally. Throw away all infected products and toss any boxes found in your pantry, even if their contents are sealed.

Weevils often live inside cardboard boxes and can easily jump to new dry food products if not properly removed from your pantry. This will kill any larvae that are still living in the food. Freezing dry foods after buying them from the supermarket can also be a good preventative measure to ensure there are no active larvae hiding in your food. Once all infected products have been thrown away, completely clear your pantry shelves.

Weevils feed exclusively on grains, seeds, nuts, roots and even some fruits. Unlike fleas or ticks, they do not have a parasitic relationship to either human beings or common household pets.

And, unlike ants or wasps, weevils will not attack when threatened. Weevils have a flight over fight instinct. When threatened, weevils will scatter and attempt to find the quickest route of escape.