Beetles are the largest group of insects, there are over a quarter million species. They occur almost everywhere: some live and breed in lakes and ponds; some feed on the leaves of trees and shrubs; some feed in trees, ﬁrewood, and structural wood; and some feed on grain, Hour, wool, and leather. The most common indoor beetle pests are those that infest stored food and natural fabric.
Beetles have four stages of development: egg, larva, pupa, and adult.
There can be several generations a year, especially when they live indoors. Adults and larvae have chewing mouthparts, but adults usually do not feed much and do not live long. The larval stages cause damage by their feeding, and these stages can live for months or even years, as in the case of some wood—infesting beetles.
Wood is a source of food for several beetle species. Some attack the trunk of live trees, others infest logs, and other species infest processed wood used for house framing, furniture, and flooring. In all these cases, it is the feeding tunnels of the larval stage that decreases the strength of the wood. Wood-infesﬂng species, such as powderpost beetles, can complete several generations in wood framing and threaten the stability of the structure. The larvae have the ability to digest cellulose, or in the case oflyctid powderpost beetles, they utilize only the starch in the wood.
Stored flour, bread, noodles, and other grain products can be infested with beetles.
There are several species of ﬂour beetle that are common in households around the world. It is almost impossible to store or process Hour without having some level of infestation. Although it is the larvae that feed on the product, it is the adult beetle that penetrates storage bins and packaging materials to spread an infestation. Whole grains, such as wheat and rice, can also be attacked by beetle adults and larvae.
Wool fabric, leather, and other natural materials are attacked by several species of dermestid beetle. Many of these species are called carpet beetles because of their association with carpeting that was at one time predominately made of wool. The carpet beetle is one of only a few insects that can eat and digest wool, leather, and animal hair. However, it is not limited to these materials, but will feed on a variety of stored food products, dead insects, and dead animals that may occur indoors or outdoors.