DESCRIPTION: A subtle and easily overlooked gall caused by a tiny mite.  The galls are seen as blister-like bulges on the upper surface of the leaf and are of a contrasting yellow coloration.  On the corresponding underside there are felted areas laden with erineum hairs in which the mites dwell. DISTRIBUTION: Uncommon but seemingly spreading. Most records though are from central and southern Britain. HABITAT: Found on the leaves of Turkey Oak.