Children (8 direct children, 8 direct and indirect children):
Helianthus nuttallii subsp. nuttallii
Nuttall's sunflower
Helianthus nuttallii subsp. parishii
Parish's sunflower
Helianthus nuttallii subsp. rydbergii
Rydberg's sunflower
Helianthus nuttallii subsp. canadensis
Helianthus nuttallii subsp. coloradensis
Helianthus nuttallii var. rydbergii
Helianthus nuttallii var. subtuberosus
Helianthus nuttallii f. verticillatus