Common Elderberry, a native species, has been added to the USWildflowers database (06/01/2011.)  Scientific name is Sambucus nigra ssp. canadensis.   It is also known by the common names American Elderberry and American Black Elderberry.  Photo below was taken in Walker County, GA on May 31, 2011.

Common Elderberry, American Elderberry, American Black Elderberry – Sambucus nigra ssp. canadensis