Planting a garden that is wasp friendly provides organic pest control
The smoky-winged beetle bandit wasp, on Virginia mountain mint (Pycnanthemum virginianum). This wasp helps scientists track the emerald ash borer, a devastating invasive beetle that is killing native ash trees.
The Eastern cicada-killer wasp must dig each burrow in her nest so that it is large enough to fit the various species of cicadas that she brings inside to sustain her young.
The nest of the bald-faced hornet (Dolichovespula maculata), with its many layers of combs enclosed in an envelope, is fiercely defended and requires a wide berth to avoid a sting.
If the wasps had been nectaring on flowers like sumac or goldenrod, their most-visited woody and herbaceous plant choices, they would have paid us no mind. But when we threaten their nests — the home to the next generation — their best defense is a good, and painful, offense.
To dig its multicellular nest, the great golden digger wasp female uses the same vibratory mechanism that bees use in the buzz pollination of flowers, “making a sound like the dentist’s drill”.
A mason wasp on fleabane (Erigeron). Simple, shallow flowers are most accessible to wasps, which have shorter tongues than bees do.
Plant families with such flower forms include carrot relatives such as rattlesnake master (Eryngium yuccifolium) and golden Alexanders (Zizia aurea). Asters and their kin, including goldenrod (Solidago), fleabane (Erigeron), tickseed (Coreopsis) and boneset (Eupatorium perfoliatum), are also especially attractive to wasps.
So are mint family members, including various mountain mints (Pycnanthemum), horsemint (Monarda punctata) and bergamot (Monarda fistulosa), and likewise milkweeds (Asclepias) and their relative dogbane or Indian hemp (Apocynum cannabinum).
Social wasps like the Northern paper wasp (Polistes fuscatus) form colonies, living in multigenerational nests during breeding season to rear the next generation.
Yellowjacket females, probably the wasp most often responsible for stinging humans, search out pre-existing cavities, like rodent holes in the ground, when they are emerging from winter hibernation in early spring. Try closing up those holes proactively.
And if you had a ground-nesting colony in the yard last year, look there first, Ms. Holm recommended, because wasps will often search for and initiate a nest near the site of their natal one.
Similarly, check eaves, overhangs and birdhouses early and regularly for any sign of the construction of a nest comb, she said, “when maybe there is only an occupant or two involved.”
Yellowjackets (Vespula maculifrons) busily nectaring on biennial Korean angelica (Angelica gigas) in the garden won’t take notice of a passing human. But these social wasps will fiercely defend their nests.