The gall mite Aceria iteina causes galls to form on the leaves of Grey Willow, Goat Willow and Eared Willow.  The galls may be hairy in appearance, 2 to 4 mm tall and narrower at the base looking rather toadstool-like. 

Gall

Gall:  Please provide good photograph showing the galled leaf and state the host plant species.

Areas where Grey Willow, Goat Willow or Eared Willow occur.

When the host species are in leaf.

True status in Britain is difficult to determine due to lack of records, but it seems to be rather infrequently recorded.

Infrequently recorded in Leicestershire and Rutland.