New Perspectives on Pierce's Disease in the North Coast
Pierce's disease (PD) has reemerged in Napa and Sonoma counties, where disease incidence has been higher than usual and the distribution of infected vines within vineyards is different than in prior years. Researchers are investigating a number of biological and environmental factors so that ecology-based disease management strategies can be devised and implemented. New findings point to the potential for vine-to-vine spread in vineyards, as well as spittlebugs being additional disease vectors.
Additional observations pertinent to PD management:
PD symptoms in the first year can be subtle
Severe pruning is ineffective
Infected vines should be removed to reduce secondary spread
Vector control measures may need to be adjusted
Read more about the research led by Rodrigo Almeida, UC Berkeley; Monica Cooper, UCCE Napa County; Matt Daugherty, UC Riverside; and Rhonda Smith, UCCE Sonoma County.