We have yellow jackets infesting our birdhouses and don't want to use pesticide to get rid of them because the birds won't come back. We covered them with garbage bags and zip tied them so they can't escape, but after 7 days, they are still alive!! What do you suggest we do now and in the future???
Yellow jackets are ground nesting wasps, so you likely have paper wasps or another related insect. If feasible, you could cover, remove, and deep freeze the bird houses to kill the wasps. You can also read the label on a wasp control insecticide; the label will tell of wildlife considerations including dangers to birds.
I believe this response is not quite accurate since yellow jackets are also cavity nesters, so they would nest in a birdhouse as well as the ground. It's not feasible to try to freeze the birdhouses that are in a bag screwed to a 4x4 post. How would we get the birdhouse off the post without disturbing the live yellowjackets since the bag is zip tied on the post? The wasp spray says not to spray near fish, so I would think it would be toxic for birds as well. Someone has to have a better answer!!!!!!
If you can leave the bags in place the wasps will eventually die from lack of food and water. For next year, consider using a poison baiting system the will greatly reduce the number of wasps in the area (see http://www.livingwithbugs.com/yellowjacket_bait.html for a discussion of baits; note, this is my personal site, your Extension office may have other suggestions). These baits only work for the scavenger species but these are the ones most likely to build troublesome nests.
Thank you for your more sensible answer! We will be on it next year!