A little over a year ago, the leaffooted bug (on the cover) was, for the first time, implicated in epicarp lesion of pistachios. Now it has been learned that several other species of true bugs can also cause some pistachio nut disorders. A fungus is the culprit in other cases. Still others remain a mystery. Cover photo by Jack Kelly Clark.

This research was supported in part by financial assistance from the Pistachio Commission of California. The cooperation of pistachio growers, processors, farm advisors, and other technical personnel is gratefully appreciated. Several of the photographs were taken by Jack Kelly Clark, Visual Media, UC Davis.