All stages are tiny and best viewed with a microscope. Larvae and nymphs are white to orange and 0.10–0.12 mm long. Adults are white to (typically) orange and have a worm-like appearance. They have two pairs of developed legs near their heads and can be 0.16–0.23 mm long. All stages feed on stem bud tissue by extracting sap from plant cells. This induces the development of galls 5–30 mm in diameter, which serve as protective housing to hundreds of mites. Galls are the best indication of mite presence. As galls grow, they become increasingly hairy until they senesce, at which time mites migrate to new buds to form new galls. Galls may develop faster and have greater impact at hot, dry sites; mite numbers appear to be greatly reduced during overwintering. There can be several generations per year, and all stages are capable of overwintering within new buds.