During July and August, distal portion of stem wilts, turns brown. In spring conspicuous dieback of terminals. It is difficult to assess impact . Heavy infestation will not kill plants, but there may be some yield reduction. Don't need to remove prunings because tip will dry out.
Several wasps give some biological control.
Stem borer, Oberea myops Hald. Oviposit in current season's growth near tip in June or July. Larva feeds in cane, adult emerges after about three years. Shoot girdling associated with oviposition, tips wilt. As larva tunnels down, whole cane affected, leaves turn reddish-brown, drop.