Larvae bore beneath the bark and sometimes into the wood on tree limbs, trunks, and main roots. Larvae are generally creamy white, elongate, and cylindrical. Dogwood twig borer. Three black spots, arranged in a triangle is visible on the top of the thorax. The larva, which is yellowish and legless, bores into the twig.
Damage usually results in wilted leaves or drooping girdled tips.
Larvae tunnel within the center of the twig, making a series of holes in the twig. Larvae push the boring dust and frass out of the twigs. In most areas, this insect requires two years to complete its life cycle. This insect is one of the most commonly encountered roundheaded borers. Adults feed on pollen, especially of goldenrod, and larvae bore and feed in black locust.