Vineyards in Sonoma County have been placed under quarantine after the discovery of 25 light brown apple moths.
Apple moth larva are a threat to grape crops; by gnawing at the leaves and fruit they can make them susceptible to rot.
The moths were first noticed in California in 2007 and have been trapped as far south as Santa Barbara County, but San Francisco and the surrounding counties of San Mateo, Alameda and Contra Costa are the most heavily infested.
The newest quarantine is an 18 square-mile area near Sebastapol within the Russian River Valley AVA, according to Sonoma County Wine Grape Commission president Nick Frey.
The quarantine zone affects some 280 acres of vines, some apple orchards and numerous plant nurseries and landscaping companies.
The United States Department of Agriculture (USDA) had hoped to eradicate the bugs quickly, but they appear to be spreading north.
‘Growers feel crop damage isn’t going to be much of an economic problem,’ said Frey. ‘The present problem is the quarantine, which means a slowdown and extra work at harvest… it will add cost and inconvenience at least.’
Frey explained that researchers are looking into the possibility of using a parasitic wasp from New Zealand to combat the apple moths.
Written by Tim Teichgraeber