Although most of these are checked by natural controls, some plant damage occasionally will take place. Few insecticides are registered for use on elderberries, so controls must be primarily cultural.
Elder Shoot Borer
The larval stage of the elder shoot borer, Achatodes zeae (Harris), is a worm that bores in the stems and shoots. The adult moth lays eggs in July and August in canes at least 1 year old. Eggs hatch the following April or May. The larvae feed first within the unfolding leaf whorls, then bore into new lateral shoots. When partially grown, they migrate to the ground shoots, entering these at the bases and feeding upwards into the shoots. When the larvae are fully grown in mid-June, they leave the ground shoots and tunnel into dead canes to pupate, leaving small piles of frass (sawdust) on the ground at the base of the old wood. To control, prune out infested shoots or canes. Eliminate dead canes to discourage pupation. Remove old canes with holes or with piles of frass at their bases. Destroy all prunings.
Larval cecropia moths, Hyalophora cecropia (L.), are large caterpillars that can remove much foliage during feeding. They are most abundant near wooded areas. Control them by hand removal and destruction.
Certain species of aphids occasionally are found feeding on elderberry. Although feeding may cause stunted and distorted leaves, usually only a few terminals are involved. If aphids become numerous, wash them from the plants with a strong spray of water, or prune out and destroy the infested terminals. Insecticidal soap or oil may control aphids.
(Courtesy of and adapted from the University of Wisconsin)