We've had an annual problem with yellow jacket nests. Now that I've read about them, I understand the importance of eliminating the early visible nests and the new queens in Spring and early summer. Meanwhile, just for others' benefit: each year the yellow jackets manage to build large nests in roof cavities of our home. One year they swarmed so badly on our bedroom deck that we couldn't use it. An exterminator told us to wait and let the winter cold kill them, which it did. Next spring we noticed a stain in our bedroom ceiling and weakness in the ceiling wallboard. The exterminator confirmed that the bees were dead, leaving a 4' x 4' mess of dead, rotting bees in the ceiling. Luckily, we couldn't smell it because it was confined to the crawl space, but I'm glad we didn't send anyone up there to destroy while the bees were alive--very dangerous! The rotting nest weakened the ceiling, which might have collapsed into our bedroom from the moisture and weight! We hired a carpenter who removed a 2'x2' piece of ceiling and pulled out the mess, then replaced and repainted. Expensive! So now that we know about preventing the bees from building such a large nest, we can try to prevent by non-toxic means, i.e. finding early nests and killing the queens. We unfortunately have what seems like a big nest in our front entrance overhang, so must deal with that. I don't like to kill any creatures but prefer to prevent next year. We'll have to get rid of these, as they are aggressive and we need to use our door! Thanks for such a useful forum.