small-flower prairie wallflower —  Erysimum coarctatum {mustard family — Brassicaceae (Cruciferae)}
Flora of the Yukon Territory, Cody, p. 350b
 { 1/320 sec, f5.0} – {Hidden lakes, Whitehorse, Yukon} – {30/08/08 Saturday, August 30, 2008; 4:26:05 PM}