Foliage may discolor or drop prematurely. Feeding damage may weaken limbs and trunks and can kill branches or entire plants. Many of the wood borers, however, are secondary pests that develop because trees lack proper care or are injured or dying from other causes. These are common pests of conifers, and some species attack woody nonconiferous plants. Bark beetles commonly attack trees weakened by other factors, such as drought stress, disease, injuries, or lack of proper cultural care.
Most adults are dark red, brown, or black.
Females of most of the bark beetles bore a tunnel or gallery in which they lay eggs at the interface between bark and wood. This group includes pine beetles, red turpentine beetle, engraver beetle, elm bark beetles, shothole borer, etc. Limbs or entire trees, especially young trees, may be killed by these borers. Most flatheaded borers do not attack vigorous plants. Larvae bore tunnels beneath the bark and sometimes into the wood.