This is close to bicolor, with similar distribution in North America. It differs as follows (Isely 1990; W): corollas mostly 12-15 mm long (versus 8-11 mm); calyx lobes (at least the lowest) longer than the calyx tube (versus equal or shorter); leaflets with L/W = 2-3 (versus 1.5-2); racemes lax and drooping (versus erect or strongly ascending); stems many per crown (versus 1 to several), purplish when young (versus brown).