Grape Erineum Mite, Colomerus vitis Pagenstecher
(Acari: Eriophyidae)
The grape erineum mite is very different in appearance from the twospotted spider mite. It is tiny-about 1/250 inch long-worm-like and yellow. The erineum mite overwinters under the bark of 1-year-old grape canes and crawls out onto the leaves during the summer to feed and reproduce. Several generations occur every year.
The damage due to grape erineum
mite is noticeable. On the upper leaf surface, a gall-like or blister-like
erineum forms, and on the lower surface, a white, dense growth of abnormally
curled plant hairs occurs. The mites feed and reproduce within the whitish plant
growth on the undersurfaces of the foliage.
In situations where severe infestations become established, reduced vigor and impaired vine growth could result from feeding by the mites on the new leaves. The mites may be introduced into a vineyard on infested nursery stock.
Current pesticide recommendations may be found HERE