Populations of a newly invasive species, the Virginia creeper leafhopper (Erythroneura ziczac), have been detected in some vineyards in Northern California, from the Oregon border to the Northern Sacramento Valley, Northern Sierra foothills, and Lake and Mendocino Counties.
Thus far, the problem is being reported primarily from backyard vines or organic vineyards. Distribution in the California counties where it has been reported is not yet well understood. Although not yet found in Napa or Sonoma Counties, proximal populations are located in Lake and Mendocino. For additional information on identification of this species, refer to a video prepared by UC Cooperative Extension Advisors.
Damage from this species can be much more severe than Western grape leafhopper, in some cases resulting in complete defoliation when control measures are not properly implemented. In many regions of California, the Western grape leafhopper is under control by natural enemies--a complex of parasitic wasps of the genus Anagrus that attach leafhopper eggs. At this time, Virginia creeper leafhopper (VCLH) eggs do not appear to be parasitized by the species of Anagrus present in California, however a thorough investigation has not occurred. Without effective controls, VCLH populations can reach very high levels, especially in backyard and organic vineyards.
Additional information on Virginia creeper leafhopper will be presented by Dr. Lucia Varela, during a "Pest and Disease Update" that is scheduled for March 6, 2013 at the Yountville Community Center