This giant ground wasp, the Cicada Killer, hunts cicadas as a food source for their young. This giant wasp can dig a 4-foot burrow in the ground with several branches and cells. One to four cicadas are placed in each cell for the larvae to eat.
The female paralyzes the host (cicada) by stinging it, then carries the cicada by dragging or flying to the nest. One egg is placed on the last cicada in each nest.
Cicada killers are usually considered beneficial insects since they destroy plant feeding cicadas. Also, they rarely sting except when the females are handled. However, under certain circumstances such as when elderly persons or young children are present in the breeding areas one may want to discourage their presence. This can be done by eliminating or reducing the breeding area which usually consists of exposed, sandy soil. This area can be mulched or covered with grass. Labeled insecticides can be applied to the nesting sites to kill the wasps.
For more information see this site: http://www.entnemdept.ufl.edu/creatures/beneficial/cicada_killers.htm