This has been generally misidentified as R. bifrons Vest in manuals; see also notes under armeniacus (Correll & Johnson 1970; Cr, RAB, St, W). R. serissimus Bailey has been indicated as the appropriate name by ongoing revision of M. Widrlechner for the Flora of Missouri (G. Yatskievytch, pers. comm.), and treatment as pascuus in FNA 9 remains uncertain (L. Alice & D. Goldman, pers. comm.). The plant has become widely scattered in southeastern states during the past 50 years, often spreading along rights-of-way: "it can be quite aggressive, often forming impenetrable thickets" (D. Goldman in FNA draft, pers. comm.). Flowers are pink (to various degrees); lower leaf surfaces have thin to dense gray-brown pubescence; primocane leaves mostly have only 3-4(5) leaflets, but often with lateral lobes; stems are erect at first but usually overarching, and sometimes trailing with rooting tips; plants are rarely more than 2 m tall. The taxon may have originated from hybridization between an Eurasian plant in the bifrons group and a native plant in the cuneifolius group (such as R. longii Fern. of Atlantic states). In some characters, it resembles R. cuneifolius Pursh (Sm, W), which has been reported from Ky. (BA) but probably in error (M). R. cuneifolius has more bluntly obovate, coriaceous leaves, and stems more erect but usually under 1 m long; it is largely restricted to sandy soils on the Coastal Plain and Piedmont, east of the Mississippi Rv.