Campsomeris plumipes (Scarab-Hunter Wasp) ♀.
Size: approx. 10 mm. Photo: 07/19/11, 9 am.

A scoliid wasp: Campsomeris plumipes or scarab-hunter wasp. The bug guide lists five genera for this family. They are predators on white grubs (Scarabaeidae), which they use as food for their offspring. The adults--as can be seen--nectar on flowers. 
bug guide (this photo):