Roundheaded Borers (excluding Asian longhorn beetles)

ROUNDHEADED BORERS
One of the families of beetles with the largest number of species is the Cerambycidae.

DESCRIPTION:
The adult beetles in this group are called longhorned beetles because of their long antennae.
The immature stage of most longhorned beetles is a woodboring larva called a roundheaded borer.
There are hundreds of species of longhorned beetles and many are very common. The beetles vary in size from 1/4 to 3 inches long. The longhorned beetles are attracted to dying, freshly cut or recently-killed trees where they lay eggs on the bark of the green wood.

The larvae emerge from the eggs and burrow into the tree and spend one to three years tunnelling through the wood. Tunnels may be just under the bark or in the heartwood, are usually about the size of a lead pencil, and are packed with coarse sawdust.
The larvae are wormlike and white to yellowish with a brown head, round-bodied and deeply wrinkled. Holes and piles of sawdust mark where the adult beetles emerge from the infested wood.
Adult roundheaded borers are medium to large, elongate, cylindrical beetles that are often brightly colored. They have long antennae, so are sometimes called longhorned borers or beetles.
One common species, the poplar borer (Saperda calcarata) attacks aspen, cottonwood, poplar, and willow.

LIFE CYCLE
:
Adult females of most species of roundheaded borers lay eggs in bark crevices.
The larvae bore beneath the bark and sometimes into the wood on tree limbs, trunks, and main roots. During the spring and summer the eucalyptus longhorned borer may complete its life cycle in 3 to 4 months, but in the fall and winter, it may require up to 9 months.

DAMAGE:
Holes in bark and stains or oozing liquid on limbs or trunks are common symptoms of damage by roundheaded borers. Foliage may discolor and wilt, limbs may die back, and branches or entire plants may be killed.
However, roundheaded borers attack mostly damaged or dying plants; vigorous trees are rarely attacked.