This is widespread eastern species with much variation that needs further investigation. Records mapped here include more pubescent plants that have been called var. illinoensis (Greene) Rehd., with colls. from PULA and perhaps CART (B). However, it remains uncertain if that midwestern segregate occurs in Ky. (F, Cr). A cultivar named "Gro-Low" is widely grown. This mostly remains less than 0.5 m above ground; leaflets are distinctly glossy and have a more obovate to rounded shape. These plants may belong to R. aromatica var. serotina (Greene) Rehder, a western taxon (perhaps species) that probably extends into Tenn. (D. Estes, pers. comm.). It differs as follows (W): terminal leaflets more broadly shaped and deeper lobed, rounded or angled at the tip (versus acute); flowers produced at or after the expansion of the leaves (versus before); pedicels 2-3 mm long, glabrous to densely woolly (versus 1-2 mm, glabrous); petals usually hairy on the inner surface (versus glabrous); fruits 5-6 mm in diameter (versus 4-5 mm);