Meehan (1898: 21) lists this specimen, Lewis 57, as Rhus canadensis Marsh. var. trilobata (Nutt.) A. Gray ex J. M. Coult. (in Contr. U.S. Natl. Herb. 2: 68. 1891). Moulton (1987a: 470) gives the location as near the mouth of the Cheyenne River, Stanley Co., South Dakota. The specimen was gathered on 1 Oct 1804. (The Lewis & Clark Herbarium Digital Imagery Study Set, ANSP, 2002) On deposit at the Academy of Natural Sciences, Philadelphia Collected by:Meriwether Lewis & William Clark Collection date:10/01/1804