Last week I talked about one of the gentle non-stinging (or better yet, rarely stinging) wasps, the Golden Digger wasp, that I have on the property. I also have a lovely blue-black wasp known as the steel-blue cricket hunter. This one too is generally a non-stinger unless you really rile it up–and by rile, I mean practically grab it while its feeding. These two are so generally gentle that they are like the bumble bees–they may fly at you to warn you that you might be a little too close, but they’re not like the wasps and hornets (sometimes called yellow jackets) that we usually think of when we think “wasp” that you generally just have to look at cross-eyed and they’ll be coming at you with a stinger!
So what is it that makes these bugs so ornery anyway? Well, generally they tend to be a more aggressive species of the bug to begin with. If you think of the range of insects, all insects have some species that are more aggressive and some that are less so.
Here in the Northeast, we are fortunate that we don’t have any real biting or stinging ants like the Fire ants. But there are many varieties of ants that can inject venom (most are in Central and South America, thankfully) and to read accounts of their stings are painful in and of themself!
We’ve heard accounts, though thankfully they did not turn out to be as fearful as projected, of “africanized” honey bees as well–our tame honey bees that bred with other imported species and became quite aggressive, often stinging in vast numbers.
And interestingly enough, wasps are defined, at least according to that great source Wikipedia, as “any of the insects of the order hymenoptera…that is not a bee or an ant. So all these insects are all more or less related.
But why do the wasps and hornets get the particularly bad rap? It’s because these insects are hunters–they eat other insects and not just nectar. Regular readers may remember my somewhat heartbreaking post on the “Parsleyworms” about a month or so ago: a hornet despatched the swallowtail butterfly larva caterpillars that were feeding on my parsley.
Why is that? Because caterpillars in general are a regular part of a wasp/hornet diet. In this case, the hornet ate one of the good guys. But in a lot of cases, they eat the bad guys. Think of how many “bad” caterpillars there are in the garden. It may help us all to feel a bit more kindly disposed toward hornets next time we see them.
As to why they tend to turn so aggressive particularly in the fall, it’s because the insects’ diets needs change and they begin seeking out sweets. Up until then, they’ve been seeking protein–hence the caterpillars and other insects they’ve been eating.
But somewhere around mid to late August (again the timing isn’t specific–the insect knows more than we do) something changes and the bugs begin to seek out sweets rather than protein. That’s why at picnics and sporting events suddenly the soft drinks are more attractive than the burgers and dogs!
In either case, these insects do sting, as we all probably know, and they can sting repeatedly. The best instinct, if you can, is not to threaten them.
I’ve attached a helpful fact sheet prepared by the extension services of the Universities of Minnesota, Iowa and Wisconsin. Not only does this show the differences between several of the hornet species but it also shows the nests. A couple of caveats however: the information on pesticides is out of date as several of the pesticides are no longer on the market; and it is fairly easy to ride yourself of a ground dwelling nest by placing a large clear bowl over their nest at night, thereby using no pesticides at all. But more on that tomorrow.