Wasps are a predator insect. They feed on other insects and their young, providing population control for agricultural pests, fleas and flies, among others. Several types of wasps live in the ground, and while there are circumstances in which you must destroy their colonies, whenever possible it is a more environmentally sound practice to simply leave them alone.
Yellow jackets will build their paper wasps in old rodent dens below the ground. They construct these out of chewed wood fiber and saliva, shaped into cones and stacked. These small, shiny yellow and black wasps are colony dependent, and go dormant in the winter, when temperatures drop bellow freezing. Because of this dormancy, they become aggressive scavengers in the fall and may become more disruptive of human activity. Yellow Jackets can sting more than once, but generally will not sting unless they feel they are trapped, or their colony is threatened.
Cicada killer is the common name for the largest of the digger wasps. They can get up to 2 inches long at full maturity. Cicada killers are black with yellow markings on the thorax and abdomen and rusty colored wings. They are considered solitary, and do not act as members of a colony, but rather live and raise offspring independently. Cicada killers are named for the female wasps of their type, who paralyze cicadas, and bury them in underground tunnels for their young. Each tunnel, is about 2 feet deep, and the diameter of a quarter, and designed to hold 2 cicadas and a wasp egg. After laying her eggs, the female wasp will seal the tunnel, and abandon her young. Grubs hatch and feed on the cicadas, and emerge from the nest as mature wasps the following summer. Only the female cicada killer has the capacity to sting, and she will not unless provoked.
The term theadwaisted wasp is used to refer to both blue and gold digger wasps. These wasps overnight in ground nests but emerge at dawn and spend the whole day looking for food. Like the cicada killer, they are solitary insects that live and work alone, lay eggs, and leave their young to develop independently from the nest. The golden digger wasp reaches a mature length of about an inch, and has a reddish orange abdomen, with a black tip. Like the cicada killer they build provisioned tunnels in which to lay their young. The gold digger wasp will paralyze and store a great variety of prey insects for their young. The blue digger wasp is a black bodied wasp with metallic blue wings, and a total body length of three-quarters of an inch. It fills its nesting tunnels with grasshoppers and crickets.