Grapevine Killing Insect Could Threaten Napa Wine Industry: Agriculture Commissioner

NAPA COUNTY, CA -- The Napa County Agricultural Commissioner's Office on May 9 urged county residents to buy plants only at local nurseries to avoid the presence of an insect that could threaten the county's wine industry.

The county's new "Think Local, Plant Local" public information campaign comes during Glassy-Winged Sharpshooter Awareness Month.

The insect, seen in the above image, lays eggs on the underside of leaves, but adult sharpshooters can be anywhere on a plant or tree.

The adult sharpshooter bores through the woody pulp of plants and sucks out water that plants need to thrive, and the resulting Pierce's Disease can be found in dozens of plants including grapevines.

Residents, gardeners and landscapers are asked to purchase plants only from certified retailers in the county that comply with a strict inspection program. All commercial grape stock shipments in the county are
inspected before planting.

The county's plant inspection and insect trapping programs have kept the sharpshooter from becoming established in the county for 15 years, but a sharpshooter egg mass was found in April and two were found in 2016.

The value of Napa County's grape crop in 2016 was $683 million, according to the annual crop report.

Bay City News contributed to this report/Image via Stephen Osman/Getty Images