Question of the Week © 2017 Mike McGrath
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Are 'Yellow Flying Insects' Honeybees? Or Yellow Jackets?
Q. You mentioned Yellow Jacket nests on a recent show and I found the timing serendipitous, as I just discovered 'bees' living in a stone wall in my yard. I think they're Yellow Jackets, but have not wanted to get close enough to be sure. In any case, there are a lot of them and they are yellow. How would you suggest I deal with these bees?
--- Sean in Alexandria, Virginia
A. Well first I have to correct Sean—and pretty much everyone else out there. Yellow jackets are in the wasp and hornet family and are not bees of any kind. So if Sean has yellow jackets, he has wasps, not bees.
What's the difference? The vast majority of bees (there are thousands of different kinds) are either stingless, gentle or both. In the bee family, pretty much only honeybees sting—and they don't like to do it because they lose that stinger and die. But many members of the wasp family do sting (yellow jackets actually like to sting) and they can sting repeatedly without any harm to themselves.
Now, if these 'yellow insects' were coming in and out of a hole in the ground, they'd definitely be yellow jackets; honeybees just don't nest in the ground. But we've gotten lots of calls over the years from people with yellow insects going in and out of a hole in the side of their home who turned out to have an escaped 'feral' (or 'wild') colony of honeybees, which are prized by beekeepers for their stamina.
And when we told Sean that yellow flying insects living in a stone wall might be an escaped honeybee colony, he responded "I know that the bee population has been struggling, and I don't want to wipe out a colony if they're not Yellow Jackets." Good man!
Now let's compare and contrast:
• Both insects live in very large colonies. A big yellow jacket nest can contain thousands of the aggressive wasps, but a wild honeybee hive could be even bigger, and might house tens of thousands of the hugely-important pollinators.
• Both insects are yellow with black markings.
• But yellow jackets are a brighter, shinier yellow. They're hairless and have that famously distinctive thin 'wasp-like waist'.
• Honeybees are fatter, less brightly colored and look kind of fuzzy.
• Yellow jackets are also much more likely to just come after you, while honeybees aren't aggressive unless you approach the hive.
If honeybees you have, contact your local beekeeper's association to see if someone wants to come out and possibly move the hive (which they would probably do in late fall or early winter).
Or you could just leave them alone and enjoy the benefits of their pollination. (And for potentially a long time--unlike yellow jackets and other wasps, honeybees will continue to use the same nest year after year.) But let's be clear that you need to call for the beekeepers if the nest is in the walls of your house; all those bees and their honey can make a huge mess.
If they are instead dangerous and aggressive yellow jackets and they're anywhere near a home, the nest must be destroyed. But despite what so-called experts will tell you, poisonous insecticides are not a good choice for this; they just don't work--insecticides can't penetrate the complex structure of the nest.
Instead, wait until the cool of late evening or dawn when any nest guards will be absent or sluggish. But just to be safe, take a sprayer with horticultural oil (or even better, a product like Pyola that combines oil with a small amount of natural insecticide) along with you and spray any wasps that come near you. Even a can of a cooking oil spray like Pam will work; oil sprays are highly effective against single insects. Then:
• If the nest is in an open, easy-to-access flat area, just place a heavy glass bowl over the hole. They can't dig a new way out and will cook inside the nest over the next week or so.
• If the nest entrance is in a more complex area (like a stone wall), place the hose of an old canister vacuum nearby—again, when the air is cool and the yellow jackets are sluggish—but wait to turn it on until you have a clear exit path. The preferable way to do this is to have the machine switched on but not yet plugged in; then you can start it up from a distance using the plug or an extension cord. Either way, the wasps will attack the noisy machine and be sucked inside. When you see no more yellow jackets, cover the hose end with duct tape and then turn the machine off and let it sit in the sun for a few days. (This is my personal preferred method. I've gotten rid of four or five nests over the years with a beat-up old canister vacuum. I just love watching them fly up to the hose, hover for a second and then—zip!—they're gone.)
• You can do essentially the same thing with one of those 'bug zappers' sold to kill mosquitoes. (In fact, this may work better on the Hole in the Wall Gang.) Put it in position, turn it on from a distance and the wasps will attack the buzzing intruder until they're all zapped.
And don't worry about the actual nest; it won't be re-used by future yellow jackets—they always start fresh in the Spring.