Although female Cicada Killer Wasps rarely sting unless disturbed, homeowners may become alarmed or scared because of their very large size (almost two inches) and foraging habits in unwanted areas. These solitary wasps may become a nuisance when they dig holes in lawns, sand base volleyball courts, flower beds, gardens, and golf course sand traps, kicking out a six to eight inch diameter horseshoe-shaped pile of dirt (mound) around the nest entrance.
Males have in particular aggressive territorial behavior, but have no sting. Females are challenging to provoke, can sting, but rarely do. The female wasps aren’t aggressive and control is rarely needed except in unwanted places. Adults appear in mid to late summer (July and August) causing special concern to individuals with young children.
How you can Identify Cicada Killer Wasps
The adult cicada killer is a very large (1-1/8 to 1-5/8 inches long), robust wasp with a black body marked with yellow across the thorax (middle part) and on the first three abdominal (rear part) segments. The head and thorax are rusty red and the wings russet yellow (brownish). Legs are yellowish. Coloration may resemble yellowjacket wasps. Life Cycle and Habits
Solitary wasps (such as a cicada killer) are very different than the social wasps (hornets, yellowjackets and paper wasps). Cicada killer females use their sting to paralyze their prey (cicadas) rather than to defend their nests. The female wasps are non-aggressive and rarely sting unless touched, caught in clothing, disturbed by lawn equipment, etc. Though males aggressively defend nesting sites, they have no sting. Adults feed on flower nectar and sap exudates.
These wasps are widely seen in late summer skimming around the lawn, shrubs and trees searching for cicadas. Cicadas are captured, paralyzed by a sting and used for food to rear their young. After stinging a big cicada, the female wasp drags it up a tree, straddles it and takes off toward the burrow, partly gliding.
When trees aren’t available, the cicada (prey) is dragged to the burrow on the ground. Cicadas are very big insects, at times called “locusts.” They sing loudly (noisily) in trees during late summer.
Overwintering occurs as a mature larva within a leathery, brown cocoon in an earthen cell. Pupation occurs in the spring lasting 25 to 30 days. Adult wasps emerge about the first week in July in Ohio. Emergence continues throughout the summer months.
Adults live about 60 to 75 days (mid-July to mid-September) while they dig new nesting holes (burrows) in full sun where vegetation is sparse in light, well-drained soils. Eggs are deposited in late July through August. Eggs hatch in one to two days and larvae complete their development in 4 to 14 days. There’s only one generation per year.
Cicada Killer Wasp – Burrows and Nests
There might be many person flying over a lawn, but each female digs her own burrow six to ten inches deep and one-half inch wide. (They don’t nest together.) the soil is dislodged by her mouth and loose particles are kicked back as a dog would dig.
The excess soil thrown out of the burrow forms a U-shaped mound at the entrance, causing unsightly mounds of earth on the turf.
This ground-burrowing wasp may be found in sandy soils to loose clay in bare or grass covered banks, berms, hills as well as raised sidewalks, driveways and patio slabs. Some may nest in planters, window boxes, flower beds, under shrubs, ground cover, etc.
Nests ordinarily are made in the full sun where vegetation is sparse, in particular in well-drained soils. Occasionally they establish in golf course sand traps. (A very gravelly or bare area is preferred.)
Cicada Killer Wasps may tunnel as much as six inches deep and another six inches horizontally. At the end of the burrow are ordinarily three to four cells where one to two cicadas are placed in each cell with one egg. When all the cells are filled, secondary tunnels are constructed and provisioned. A single burrow may eventually have 10 to 20 cells.