23 Wasps You Might Find In Your Yard: Which Are Harmless & Which To Kill

Imagine lounging idyllically in your sun-soaked garden until you notice a sinister buzzing sound. Before you lunge your book at the pesky wasp (Hymenoptera) to save your arm from developing a painful boil, step back; for there are high odds, it's merely exercising its nature-ordained right of way. As the human equivalent of introverts and extroverts, wasps are classified into solitary and social categories, with the latter accounting for a meager 1.5% of the total population. This implies there's more to wasps than the brightly colored yellow jackets, hornets, and paper wasps you've come to despise (and kill) for their stinging habits.

Like their bee brethren, wasps play the impressive role of a pollinator, with approximately 164 plants solely trusting them for the task (per a 2021 Brock et al. study). Figs and orchids are familiar examples. Similarly, with lip-smacking delight, these carnivores devour irksome critters, including aphids, stink bugs, spiders, and white flies, ensuring your plants put on their exquisite floral display come summer. Some even help decompose and clear out pests' corpses in a vulture-esque manner to feed their larvae. The best part, though? Their ecosystem services don't come at the price of a prick — they're utterly harmless and are best left alone. Read on to know if the wasps visiting your yard are beneficial, may require removal, or warrant slaying.

From June to August, black and yellow mud daubers are given to nesting around moist soil in protected areas, such as along a home's sidewalls or under eaves. Excluding their abdomen and legs that feature yellow speckles, they appear black all through, although their wings may give off an orange sheen. These under-an-inch-long, native solitary wasps feed on spiders, doing your garden a considerable service. Since their mud homes are usually annoying, rest assured that you can safely move them out without getting stung.

The great black wasp is another solitary digger wasp that has no interest in stinging homo sapiens unless threatened. They are usually found resting in cushy garden soils, pollinating plants (like milkweed and beans), or clamping down on pests like katydids and grasshoppers. They're active for a short season (July to August) throughout the US, excluding the northwest regions. Staying true to their name, they bear shadowy black, 1½-inch-long hairy frames with a gleam of blue in their wings. However, those sensitive to stings are better off keeping their distance, for they're painful without being harmful.

Although you're unlikely to recognize gall wasps, given their diminutive, brown-hued, you might have seen signs of their presence on oak trees and rose shrubs. Encompassing numerous species, they form distinctively shaped galls on twigs, buds, acorns, or foliage where the female wasps inject their eggs. Fortunately, their grubs aren't extremely damaging to their hosts, as they pupate in small numbers — stressed trees are an exception. Destroying the galls and improving trees' vitality should naturally reduce their presence. They pose no health concerns for people.

For those tired of searching for easy ways to prevent invasive emerald ash borers from destroying your trees, a smoky winged beetle bandit's nest in their yard's compacted soil will be a welcome respite. While the nests can pass for ant hills, the beetles lack ants' sly activity. Starring tiny, skittle-sized black bodies and wings, these native species can be distinguished by a single yellow stripe running across their abdomen and similarly-hued face markings. Fortunately, they're bandits only against wood-boring pests and remain docile even if a curious human pets them.

As ichneumon wasps are always on the lookout for the nests of horntails' (to lay their eggs inside the pupating larvae), they're usually found haunting stressed hardwood trees from May through July. Including their ovipositor, which doubles up as a mild stinger when they perceive danger, they measure 4 inches. Although boasting black bodies, this variety showcases significant color variation, with Megarhyssa macrurus strewn in red, yellow, and brown markings all over, in contrast to the bright orange head of Megarhyssa atrata. Often mistaken for dragonflies, their three tails are their biggest tell-tale sign.

Blue-winged wasps are renowned for their beautiful wings that appear celestial blue when the sun hits right. The two prominent yellow dots on their reddish-orange rear further add to their charm. However, they're widely anticipated during hot summers because they assist in our battles against exotic Japanese beetles and other native grubs (like June beetles). They kickstart their generational cycle by injecting eggs into immature grubs. Other times, they can be found relishing nectar from goldenrod flowers. Blue-winged wasps aren't known to sting humans.

Named after their preference to flake off wooden fibers from trees or untreated structures to hang them as their umbrella-shaped homes under protected sites like eaves, paper wasps are usually considered beneficial. As adults, they aid pollination, while their larvae gorge on caterpillars, which otherwise would eat through plants. Unfortunately, some species eat garden fruit, too, which gardeners dislike. While a stray wasp is benign — donning an ½ inch-long, rust-mottled, brown-to-black body with suspended legs (in flight) — encountering a nest full of workers in late summer will leave you stung.

Also called emerald wasps and gold wasps for the color variations — blues, greens, purples, and reds are up for grabs — cuckoo wasps are parasitoids. When flitting about and sipping on flower nectar (sometimes aphids' dew), their shimmery silhouette looks breathtaking. Still, when caught stealing into another bug's nest, they're quick to bring all their stocky armor and roll their two halves into a ball (like an Amarillo). Unfortunately, pollinating bees, fellow wasps, and silk moths are all fair game. Moreover, experts remain divided regarding losing their ability to sting, so exercise caution.

Although they belong to the paper wasp family, red wasps get a special mention because both the Carolina and rubiginosus species are eye-catching rusty red. However, they — especially the males — have pronounced black markings around the head and abdomen with brownish-black wings. These 1-inch-long wasps are pervasive in eastern parts of the US between summer and fall. As they provision their larvae with cicadas and caterpillars, some consider them useful around yards. However, they can sting when they feel endangered, prompting many to knock down their paper homes in the evening.

European hornets give homeowners quite the fright at night as they staunchly knock into brightly lit windows, which intensifies come morning when the insects are leaving lilacs, willows, poplars, and rhododendrons girdled and near-dead. They haggle with gardeners over dropped fruit, especially pears and apples, stinging them incessantly in return. While they collect yellow jackets, grasshoppers, and flies as trophies, they trouble honey bees, too. In short, they pack a lot of nuisance in their 1½ inches, yellow-banded, brown bodies, which grow redder and larger (over 2 inches) for their reigning queens — don't hesitate to banish them.

Born to put mighty tarantulas in their place, Tarantula hawks are 2½ long wasps with velvety blue-black bodies contrasted gloriously by sunny orange wings. Their ⅓-inch-long stinger has earned the spider-killer the highest pain score on the Schmidt Pain Index, which is ironic considering their adults get high on fruit juices and flower nectar, especially from milkweed and soapberry trees. In the US, they can be found as far up as Utah in the cooler parts of the summer — don't make the mistake of handling them.