Identification
Psocids (SO-sids) are soft bodied insects, less than 4 mm (3/16 inch) long with long, slender antennae and chewing mouthparts. They may have four wings or be wingless. They are generally gray or brown in color. Psocids are readily identified (under magnification) by the presence of a large, conspicuous clypeus (nose).

Biology
Most psocids live outdoors and have wings. They can be found on tree bark, tree and shrub foliage, or under stones. These psocids are known as 'barklice'. They sometimes can become quite conspicuous when they congregate in large groups. Barklice feed on fungi, lichen, pollen, decaying plants, and other organic material. They are harmless to plants and no control is necessary.

There are a few species of wingless psocids that may be seen commonly in buildings, usually Liposcelis spp. These psocids are commonly called booklice because of their association with books or paper. Despite being called 'lice', booklice are not harmful to people or pets.

Booklice feed most commonly on molds as well as fungi, grains, insect fragments, and other starchy material, including glue from book bindings. In homes, they can be found in damp, warm, undisturbed places where mold and fungi are growing. They are more likely to be a problem during summer. They are rarely damaging inside buildings but they can become a nuisance because of their presence, especially when they occur in large numbers.