The galls on the upper surface of ash leaves are unmistakable and often particularly numerous on the terminal leaves. They are small and solitary, somewhat reniform in shape, and generally scattered at random on the lateral veins. Their greenish-yellow color and shape give a striking effect on an infested leaf. Specimens were found in galls on leaves of white, Oregon, and green or red ash in California, Wisconsin, Virginia, New York, Vermont, and Canada. In Europe, Eriophyes fraxinicola (Nalepa), a closely related species of E. chondriphora, makes similar galls on leaves of European ash (Fraxinus excelsior L.).
”- Hartford Keifer,Edward Baker,Tokuwo Kono,Mercedes Delfinado,William Styer: (1982) An Illustrated Guide to Plant Abnormalities Caused by Eriophyid Mites in North America©