Grape rust mite (Calepitrimerus vitis) densities and the development of short shoot syndrome in the Willamette Valley, Oregon

Feeding by the grape rust mite can cause early season damage to developing fruiting cane shoots, particularly in grape growing regions with extended periods of cold temperatures post-bud break.  Collectively this damage is referred to as short shoot syndrome.  Shoot stunting also can be caused by physiological factors, which can be confusing to vineyard managers.  In this poster I describe the relationship between mite densities on developing shoots and the degree of shoot injury using three indices of damage.