European grapevine moth eradicated from California

US agricultural officials have confirmed the extermination of the European grapevine moth from California, which has threatened crops worth US$5.7 billion for the past seven years.

The European grapevine moth originates from southern Europe and primarily feeds on grapes.

The European grapevine moth (EVGM) was first detected in Napa County in 2009, with the infestation peaking in 2010 when more than 100,000 of the mothers 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.

In a statement released yesterday, the California Department of Food and Agriculture (CDFA) said that it had lifted quarantines put in place throughout the state following its successful eradication, with the pest not detected in California since June 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 European grapevine moth, or Lobesia botrana, is originally from southern Europe and 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.

“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 US grapes around the world”, said Kevin Shea of the Animal and Plant Health Inspection Service (APHIS).

“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.”