In Hopland yesterday, growers in Mendo, Lake and other counties met to hear the latest recommendations from U.C.'s Cooperative Extension researchers studying and learning how to combat invasions of the non-native Virginia Creeper Leafhoffer, a bug that has been plaguing North Coast vineyards.
This leafhopper has been particularly devastating to organic growers, a number of whom have abandonned organic practices in order to stay in the vineyard business, according to UCCE Farm Advisor, Glenn McGourty, who serves in the Mendocino and Lake county region. But, as the latest research shows, there's hope they could return to organic wine grape growing.
|Virginia Creeper Leafhopper|
Credit: Mike Poe, UC ANR Communications
The parasitoid also lives in Mendocino, but local specimens have not been going after the Mendocino Virginia Creeper Leafhoppers, which only recently invaded the area.
|Virginia Creeper Leafhopper eggs parasitized by the Anagrus daanei|
"We started our initial releases in July 2015 with 2,000 Anagrus daanei, and they spread into the vineyard blocks," Wilson said. Now in 2016, his group has started a much larger release program, with four vineyards in Mendocino and one in Lake County. "And we're looking for new targets," he added.
Wilson said the fairyflies reproduce up about 10 times per season, faster than the leafhoppers.
Use of the parasitoids to control the Virginia Creeper Leafhopper will reduce the amount of pesticides used in fighting the invasive non-native species as well as reduce pesticide costs for both conventional and organic growers.
For more information, or to find out how to participate in the program, visit the project's web site at http://ucanr.edu/sites/vclh/.