August 1996
Size
Larvae up to 3 ¼ inches (80mm) or more
Color
Brown, reddish brown or black
Description
Roundheaded borers are elongate, cylindrical, and
have large gnawing mandibles. The name roundheaded borer refers
to the enlarged thorax directly behind the head. They are sometimes
mottled or banded with white or gray. Adult roundheaded borers
are often referred to as longhorned beetles because of their long
and distinctive 11-segmented antennae, often longer than the beetle's
body. The thorax and wing covers on some species bear small, stout
spines.
Habitat
Most of the hundreds of species of roundheaded borers
are found in weakened, dying, and dead trees. In addition, they
feed on felled trees, stumps, and cut firewood. Roundheaded borers
feed under the bark and in the sapwood of trees. Adults often
emerge from firewood that is brought into the house and may cause
concern. They will not infest structural wood and are a nuisance
only.
Life Cycle
Adults lay their eggs on weakened and damaged parts
of the tree. The larvae bore into the tree, feed under the bark
at first, and later bore deep into wood. They may take one to
several years to mature before they pupate inside the tree just
under the bark.
Type of Damage
They bore long holes as they feed and weaken
and destroy the wood. Infested trees are often rendered unusable
for commercial purposes. Adult roundheaded borers (longhorned
beetles) do very little damage to trees and spend most of their
time feeding at flowers on pollen. A few species commonly referred
to as twig pruners will kill small branches and twigs.
Control
Insecticide control is not recommended for firewood,
simply burn the infested wood first.
