This species is listed in most older field guides as Cypripedium calceolus. In older plant lists for the Ottawa area it is listed as C. calceolus, but noting that this includes var. parviflorum and var. pubescens. Recent updated lists of Ottawa flora now list this as C. parviflorum, which in some guides is called Small-flowered Yellow Lady's Slipper, but in most is just referred to as Yellow Lady's Slipper. In other flora it is listed as Cypripedium calceolus, var. pubescens, because it does not have the red petals.