By Robert Haugh

For the last two weeks, Santa Clara County agricultural inspectors have been going door to door to recover grapevine plants that may be carrying a dangerous invasive insect.

The recalled plants were sold at Northern California Costco stores between April 21 and May 19.

Some were infested with the glassy-winged sharpshooter, a pest that can spread Pierce’s disease. The disease kills grapevines. There is no cure.

Now county officials are trying to find every plant before the insect gains a foothold in Santa Clara County.

Residents who bought grapevines at Costco during the recall period are being urged to contact the County Division of Agriculture immediately.

The county began collecting the plants July 15. Inspectors are contacting customers by phone, mail and in person. They are providing bags, disposal instructions and pickup dates.

Officials have one clear warning: Do not throw the plants in the garbage. Do not compost them. Do not move them.

Doing so could spread the insect or the disease.

Residents should remove any stakes, place the plant in county-provided bags and double-bag it. The bags should be tied securely, marked with the recall notice and placed near the front door or gate before 9 a.m. on the scheduled pickup day.

They should not be left at the curb or placed near garbage, recycling or compost bins.

County pickup is free. Customers should contact Costco directly about refunds.

The glassy-winged sharpshooter is established in Southern California but is not normally found in Northern California.

The insect feeds on plants and can transmit Pierce’s disease. Infected grapevines can die within two to five years.

An outbreak could threaten vineyards, farms and nurseries throughout Santa Clara County. It could also hurt local fruit and wine production and trigger restrictions on businesses that ship plants to other parts of California.

Residents who bought a grapevine during the recall period should call the County Division of Agriculture at (408) 918-4662 or email sccagriculture@cep.sccgov.org.

They should contact the county even if they no longer have the plant.

Anyone who believes they have seen a glassy-winged sharpshooter should also report it.

County officials are racing to contain the problem before one infested plant turns into a much larger agricultural threat.