Sacramento, California - Agricultural officials from the California Department of Food and Agriculture (CDFA) and the United States Department of Agriculture (USDA), in cooperation with county agricultural commissioners, have declared the European grapevine moth (EGVM) eradicated from California and have lifted quarantine restrictions.
The EGVM was first detected in Napa County in 2009 with subsequent detections and quarantines in the counties of Fresno, Mendocino, Merced, Nevada, Santa Clara, Santa Cruz, San Joaquin, Solano and Sonoma in 2010, 2011, and 2012. No EGVM have been detected in California since June 25, 2014.
"It is no easy feat to eradicate an invasive species, especially one like the European grapevine moth when it gains a foothold in a place as hospitable as California's prime winegrape growing region," said Karen Ross, CDFA Secretary. "But together with growers and stakeholders and this community and others , we have done just that. It's no accident that this program has performed so well when you consider the ground we've covered together before and the relationships in place because of the ongoing, cooperative program created by this industry years ago to combat Pierce's disease and the glassy-winged sharpshooter."
The infestation peaked in 2010 when more than 100,000 EGVM were detected. Following an intense period of coordinated trapping, treatments and other detection and response activities, the detection numbers dropped dramatically to 144 detections in 2011. As a result of the collaborative efforts between, USDA, CDFA, county agricultural commissioners, grower liaisons, University of California Cooperative Extension (UCCE) and especially growers, the quarantine area in California shrunk quickly from a high of 2,334 square miles in 2013 to 446 square miles in 2014.
"This destructive invasive species put grape and stone fruit crops worth more than $5.7 billion at risk and threatened to close valuable export markets for U.S. grapes around the world." said APHIS Administrator Kevin Shea. "Eradicating EGVM has been a top priority for APHIS, and together with industry, state and local officials, growers, university scientists and extension services, we were able to successfully invest in and implement the right tools to safeguard California grapes. The collaborative strategies used by the EGVM eradication project will be a model for addressing future pest incursions."
Napa County Agricultural Commissioner Greg Clark added, “Over the past seven years our growers, their neighbors, and certainly our staff here in Napa County - and in all of the counties that have dealt with this pest and this quarantine - have done a lot of the heavy lifting to get us to this point. Eradication of the EGVM is an important accomplishment in itself, but this program is perhaps even more valuable as an example of what we are capable of as a community."
The EGVM, or Lobesia botrana, is originally from southern Europe. The pest primarily damages grapes, but has also been known to feed on other crops and plants. First and second generation larvae feed on flowers and developing berries in the spring and summer. Third generation larvae occur in August and September and cause the greatest damage by webbing and feeding inside berries and within bunches, which become contaminated with frass. Feeding damage to berries also exposes them to infection by Botrytis and other secondary fungi.