How many times have we traveled into California through the Agricultural Inspection and wondered if these efforts really matter? With the abundance and importance of farming in our state (for ourselves and our country), keeping invasive pests from ruining our plants, trees and vines helps all of us.
So when we learned earlier this week about Glass-winged Sharpshooters having been found on uninspected grapevines at a Costco in Sonoma, this quickly became a huge issue to educate people. It's amazing how many people buy plants (not just grapevines for your backyard) from Costco. (And credit to Costco for tackling this discovery of insects on their plants...not only with their staff calling the Ag Department, but also sending out press releases and offering refunds on plants to try to get this under control!)
But let's step back a bit here and explain why this is something to take seriously. A Glassy-winged Sharpshooter (GWSS) may sound like some sort of sexy character from a sci-fi movie or new video game. But alas, a GWSS is small (about 1/2 inch long) flying bug, kind of like a leaf-hopper. Here's what makes them so dangerous. Glassy-winged Sharpshooters are the vector (carrier) of Pierce's Disease for grapevines. And in grapes, Pierce's Disease (which doesn't allow fruit to ripen properly, discolors the leaves (so they don't work well), shrivels the leaves, and can kill the vines. Oh, and Pierce's Disease is incurable.
Now, why worry about the GWSS? Well, it turns out that GWSS thrive on all sorts of plants, using them as hosts. So if there aren't any grapevines around, they can live on almost anything as they travel and spread. Thus getting control of an outbreak (like in Southern California some years ago) is time-consuming, expensive, and equates to many vineyards being lost.
Now to this particular situation. Some how, grapevines with GWSS made it into Costco stores without having been inspected by the Ag Department (and given clearance). That means that every Tom, Dick and Harry that might have bought grapevines at a Costco from April 21st (the start) until about last week will have potentially helped the GWSS move into previously clean areas. But it is possible, because of the GWSS ability to use other plants (like ornamentals) as hosts, that they could be on that maple tree or whatever that Tom, Dick and Harry bought at Costco.
So here's the deal. If you have bought any plants from Costco between April 21st to say last week and brought them home, just take a look at them for these GWSS on the leaves/stems. If you have any questions, just call your local Agricultural Department, and they can come inspect too. For El Dorado County, our Ag Department's phone number is 530-621-5520.
Thank you all for taking this seriously, and may we be proactive in keeping Glassy-winged Sharpshooters and Pierce's Disease out of our vineyards!!!