The Great Black Wasp, scientific name Sphex pensylvanicus, is a species of digger wasp found across most of the Continental United States and northern Mexico. They are also called the Katydid Hunter and Steel-blue Cricket Hunter, though the latter name is also shared with a different wasp species.
Male black wasps are about 1.1 inches long, while females black wasps are slightly larger at about 1.3 inches long. They have entirely semi-gloss black bodies with thin waists and very spiny legs. Heavy-duty mandibles decorate their large heads, and females sport stingers on the tips of their abdomen (males do not have stingers). They have large, iridescent wings that can be folded flat over their abdomen.
They are solitary hunting wasps, and you’ll find them most active during summer peacefully sipping on nectar and munching on pollen. Their young though are a different story – they’re carnivores. An adult female black wasp will lay her fertilized eggs in an underground nest then go off to hunt katydid, cricket, grasshopper, or another similar insect to take back to the underground nest, alive but paralyzed from the mother wasp’s sting so they can be as fresh as possible for their intended purpose. Wasp eggs are then glued to the underside of the paralyzed insects, and once the egg hatches, the emerging larvae have instant access to food which they will devour as they grow and develop. Before the mother wasp leaves her eggs to their own fate, she closes the nest chamber and surrounding tunnels by filling it with soil and systematically tamping it down, often vibrating her abdomen to effectively act as a jackhammer. An interesting thing that happens is, sometimes the mother wasp may use tools such as a small leaf, twig, or pebble to aid in her efforts.
The mother wasp will spend a significant amount of time hunting food for her offspring, and while carrying paralyzed insects, she will be vulnerable to birds – particularly the house sparrow and catbird – stealing her victims. This is known as kleptoparasitism, which is when one organism benefits from another organism by stealing their caught, collected, or stored food.
Solitary wasps such as the great black wasp are much less aggressive than your average wasp and will not sting unless they feel very threatened. Their stings are painful, but will not swell like the stings from other wasps. Their stings are generally considered not dangerous, unless you have an allergy to insect stings – in which case, seek medical attention immediately.
If you find a lot of these wasps on your property and want to get rid of them, make sure you cover as much skin as possible – wear gloves, long-sleeved shirts, jeans, shoes, etc. – then spray them using a wasp or hornet insecticide spray can that shoots from several feet away so you can stay as far away as possible.
Find wasp nests on your property by keeping a lookout for the burrow entries they fly in and out off. Then saturate the burrow entries with insecticide spray or insecticide dust at dawn, just before these wasps wake and fly off for the day. Make sure you don’t hang around in the area – you don’t want angry wasp survivors exacting revenge.
If you have a wasp infestation on your property and have difficulty locating their burrows, get in touch with a professional pest control company to get rid of them safely and thoroughly for you.