This has been interpreted as a hybrid complex involving laevis, arborea or canadensis (Dibble et al. 1998; K); reportedly, 2n = 34 and 54. However, it is currently treated it as a distinct northeastern species in FNA 9 and W. A. intermedia resembles canadensis in its relatively small flowers (6-12 mm versus 10-20 mm in arborea) on erect racemes (versus drooping), but differs in its leaves at flowering more expanded, reddish and glabrescent (suggesting laevis). E.J. Palmer applied the name intermedia to a coll. of B from BOON (US): E.L. Braun #857, 3 Apr 1935, Woolper Cr., field on terrace. This identification is consistent with FNA, but further assessment is desirable.