Helianthus nuttallii subsp. canadensis R.W. Long
Helianthus nuttallii subsp. canadensis R.W. Long is a synonym sensu FNA Ed. Comm., 2006c of:
Helianthus nuttallii Torrey & A. Gray subsp. nuttallii, an accepted subspecies name sensu FNA Ed. Comm., 2006c.