Lyn,

As far as I know, not a particularly bad year with yellowjackets. But when they run low on other food sources, they will move to ripe fruits. Perhaps screening or floating row cover might help. Of course, that depends upon how large a berry patch you have.

It might help to use some of the commercial yellowjacket traps, but place them at some distance from the berries. Then cross your fingers that the pheromone-laden traps are more attractive to the yellowjackets than are the berries.

After the holidays, you might call the Oregon State University Extension Service office in Columbia County. (It's in St. Helens; 503-397-3462.)

Jean, Thanks for your post. After entering this, I talked to my immediate neighbor who said he had no problems with his crop of grapes. Apparently it's just my place, so I will start trapping early and hope for the best. I have too many plants to cover or screen. Maybe there is so much food here they don't need to go anywhere else. I was just surprised to lose every single berry, and every single grape on the whole place. It doesn't make sense. Lyn

It's possible that you might also have birds & squirrels helping with your harvests.

Jean001: There's no doubt about that. I have seen their damage, too, but the main problem was the wasps that completely covered the grapes and berries, so that you couldn't even see the fruit, and they sucked everything dry, leaving shriveled up skins. I'm frankly baffled. When I moved to Vernonia a local told me that people quit trying to garden here after about 5 years. I've never seen anything like this: raccoons, squirrels, rats, mice, voles, gophers, moles, deer, slugs, symphylans, elk, and birds, plus all the usual pests I had in Salem. I'll keep trying. Thanks for your input. I've benefited from your comments these past few years. Lyn