If anyone can give me some clues about how to go about destroying those nasty old nests the big wasps come out of, I'd appreciate it. I've tried everything from Invocation, Fear, Death Dome, etc and nothing seems to work. Thanks!

The easiest way I have discovered to destroy the nest is to cast invisibility on yourself and then avoid all the wasps as you make your way to the nests. Once you are standing right beside them simply start hacking away. Be careful as the wasps defend their nest zealously. It is much simpler to destroy all of the nests and then work on the wasps. The nests are no longer around to spawn reinforcements. Hope this helps but I bet you have already figured this out. Have fun!