They nest in the ground during summer. They are found in many habitats but most often in open, sandy areas along rivers. Nests are often aggregated. Bembix americana spinolas is one of the largest and most conspicuous sand wasps. A single developing young may eat two dozen flies.
Adults often catch flies on the wing and are remarkably fast and agile.
Their habit of hovering uncomfortably close to a person for the purpose of catching flies attracted to that individual is often mistaken for aggression. But they are even-tempered wasps, and it is possible to feed them out of your hand by presenting them with a living fly not quite capable of flight. Sand wasps are occasionally mistaken for hornets or yellowjackets becaused of their banded color pattern. Nest cells are situated on short side tunnels off a long main tunnel. Typical nests have two or three cells, and a typical female will construct five or six nests in her one to two months of summer activity.