In keeping with the pest control side of my blogging purposes, I bring to you, my loyal reader(s), some insights into the control of stinging insects, namely those of the hymenopterous variety.
Most folks that call a pest control firm tell the receptionist that they have
bees. Usually this isn't the case. It is hardly necessary to be an apiculturist to know the difference between bees and wasps or yellowjackets. We could go into the classification of insects in the order Hymenoptera in great detail, but that would serve little purpose here. Suffice it to say, if they're bright yellow instead of orange and hairy, you don't have bees.
Bees make honey, and are important contributors in the ecology web. We all know that they are pollinators; some people will remember that
colony collapse disorder has been in the news lately, and our bee colonies are in trouble. Fewer know that if you actually have bees, we are all better off if you call a local beekeeper instead of the exterminator. Many beekeepers will come and capture a feral colony if they can at no charge. Why? Well, the situation is analagous to calling a farmer if you've got wild cattle. Free livestock is a pretty good deal.
Bees (at least those that aren't of the Africanized variety) are fairly docile, and can easily be approached if you aren't the nervous type. If you just can't get a beekeeper in your area to come get your bees, and you can't afford an exterminator, an insecticidal dust is your best option. You need only treat the entrace hole. Keep in mind, though, that once you've got an inactive bee hive in your walls, loaded with honey and dead larvae and adults, you'll have another problem. The nest will be highly attractive to dermestids, fungi, and other undesirables.

Chances are, though, like most folks that call, you don't have actual bees. You have wasps. Or yellowjackets. Or hornets. Or . . . well, let's limit our discussion to the most common nuisance calls. Social wasps construct open-celled paper nests most often under the eaves on the sunny side of a structure and similar areas. If you've got a poorly built house, you're in trouble. Neglected cedar shake shingles, for example, are a haven for paper wasps. They offer cellulose for the construction of nests, and shelter as potential nesting sites.
Yellowjackets, on the other hand, usually construct nests in voids in the ground, an old stump, or even a house. Some will build aerial nests. These can be distinguished from paper wasps by their enclosed appearance. Yellowjackets are generally also distinguishable from paper wasps in flight by observing their legs: yellowjackets carry theirs next to their body, while paper wasps allow their long legs to dangle beneath them.
I guess they like to show them off.
The key here, and the difficulty, as with all social insects, is to treat the nest. This isn't terribly difficult
if the nest is in a known location, and
if you can approach and treat it safely. Dusts are superior to other insecticial formulations because of their longer residual effects, especially where yellowjacket nests are concerned. Yellowjackets become more difficult to approach as the summer wears on and the colony grows in size. And when their nest is in a void, the only exposed area that the workers must traverse is the entry to the nest - that is where you want to focus your efforts. Approach it in the cool of the morning to treat it, and if you get stung, well, that's your own fault for not calling me, the professional.
Caveat DYI, as it were.
What if you can't find the nest, or it is on a neighboring property where you can't treat? Insects are disrespectful little buggers, who don't observe property boundaries; keep that in mind. The alternative here is the trap. A number of traps are on the market, and they all work fairly well at what they claim to do. The main mistake I see here is this: people have a lot of wasps or yellowjackets flying around their favorite outdoor hangout, such as a patio. So they put the traps there.
The traps are attractive, of course, otherwise they wouldn't work very well. Consequently, every wasp and yellow jacket for several hundred yards is now visiting your patio, because you foolishly put the trap there.
So place the trap as far away from your house as possible, in an area you don't visit much, such as a neglected corner or, even better, your neighbor's house ("Hey, Bill, the yellowjackets sure are bad this year. I bought some extra yellowjacket traps and I figured I'd set one up for you, too. Naw, don't thank me - it's the least I can do.")
What can you do in prevention? Pretreat known harborage areas, pretreat sources of cellulose (like your cedar-shake shingles, or your unpainted fence - and paint that fence this year, gosh darnit!), hang out traps well in advance of the season to capture inseminated queens establishing nests, and eliminate standing water where possible (another necessary component of nest-building). Eliminate food sources by controlling pests, like aphid, that are feeding on your plants and, in turn, providing food for wasps and yellowjackets. Lastly, if you can place ant baits where wasps and yellowjackets are foraging (within the limits of the label and your state laws, of course), the effect on the local population can be surprisingly effective. Use both sugar-based and protein-based baits for maximum effect.
One last situation comes to mind - the invasion of your home by overwintering wasps (no, they don't overwinter in their nests, or return to their old ones, even though they may build in the same locations; each pupal cell is only used once). Unfortunately, areas such as attics, which are like the Bahamas to wasps looking for a place to lounge over the winter, are often poorly sealed. Use exclusionary tactics, such as fine-meshed screens, to cover areas that permit access to wasps looking for places to spend their dormant period. If you're reading this in the late winter, and it's too late to utilize this tactic, you will need to treat the areas where the emerging wasps are overwintering. Because we heat our living spaces, our homes throw off the environmental cues that wasps depend upon to tell them when to emerge in the springtime, and this can be an ongoing problem.
Alternatively, you could turn off the heat and just dress warmly all winter. Very warmly.
And if they don't really bother you, then don't bother them - yellowjackets and wasps prey on other insects while feeding their larvae,
so they're actually beneficial. They perform pest control for free.
It's okay, really. I don't mind the competition.