Answer: One pest that causes the symptoms you've described is the Japanese Weevil (not to be confused with Japanese Bettle). These weevils are very small, and drop to the ground when they perceive danger. Adults emerge from soil in early summer and skeletonize leaves as they feast. The larvae may feed on rootlets of your shrubs. Since the weevils can't fly, their lives are pretty circumspect - they probably complete the cycle right on your bushes. You can try to identify them by placing a white cloth under the edge of the barberry bush. Visit later in the day, and you may witness the adults dropping to the white surface, where you can identify them. If you want a definitive I.D. on the pests, collect specimens and contact your agricultural extension service for help with I.D. (ph# 414/335-4477). Beneficial nematodes (from Gardens Alive, 5100 Schenley Pl., Lawrenceburg, IN 47025; ph# 812/537-8650) will feast on their larvae; to prevent adult feeding, try using a neem-based repellent such as Safer Japanese Beetle Repellent (offered by Burpee) as soon as possible, before the weevils make their appearance, and maybe they'll just stay away this year! Hope this helps!
Q&A Library Searching Tips