The larvae are legless, yellow to yellowish-white and have a broad, flattened area immediately behind the head. Mature larvae are 1 inches long. The larvae damage the trees by boring in the trunk and main branches. The galleries will be filled with sawdust-like frass or excrement. Infested trees will often have cracks in the bark that ooze sap.
Initial attacks are usually on the sunny side of the tree.
Eventually the galleries can girdle the tree and cause death of the tree. Adult beetles are present from late spring to November. There is one generation a year. Vigorous trees will often produce enough sap to drown the larvae in the galleries. The only good control is to keep the trees healthy and vigorous.