Systemic insecticides, such as acephate, will give good control with minimal impact on beneficials. They have long antennae and are pale yellow with two black spots behind the head. In late June to early July, female beetles lay their eggs in new shoots several inches below the bud. The larvae emerge, bore into and down the interior of the twig where they overwinter. The following year, the larvae continue to bore downward where they overwinter in the roots.
Adults are present every year, but each insect takes two years to complete a life cycle.
Damage Adult beetles feed on the undersides of leaves along the midveins, causing the leaves to curl. Boring by the larvae causes wilting and eventual dieback of individual canes. Monitoring Examine lower branches with curled leaves for the adults and signs of feeding in June and July. Prune and cut open wilted branches to see if larvae are present. Also, check branches for sawdustlike debris that push out through small entrance holes in the bark.