Infestation by one to three females is sufficient to kill the twig or branch. Infestation becomes apparent when die-back of twigs and branches occurs. The black twig borer belongs to the tribe Xyleborini, all of which feed on ambrosia fungus and are called ambrosia beetles. The black twig borer is somewhat unique in that it attacks living plants rather than dead or dying ones. The life cycle of the black twig borer is completed in about a month.
Males spend their entire lives inside the brood gallery.
Females mate inside the brood gallery and then leave to produce new galleries. Females can reproduce without mating, in which case the offspring are all males Eggs Eggs are laid in galleries in the twigs. Larvae Larvae are grubs, white and legless. There are two larval instars. Males are about half as long and incapable of flight.