Helianthus nuttallii

Helianthus nuttallii
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Asterales
Family:	Asteraceae
Genus:	Helianthus
Species:	H. nuttallii
Binomial name
Helianthus nuttallii Torr. & A.Gray

Helianthus nuttallii (Nuttall's Sunflower) is a species of sunflower native to northern and western North America, from Newfoundland west to British Columbia, south to New Mexico and California.^[1]

It is a herbaceous perennial plant growing to 0.5–4 m tall. The leaves are opposite on the lower part of the stem, alternate higher up, narrow lanceolate, 8–20 cm long and 6–30 mm wide, with a rough texture. The flowers are yellow, produced in a flowerhead 9 cm diameter with 10–20 ray florets and a centre of disk florets; each stem bears one to a few flowerheads.^[2][3]

There are three subspecies:^[1][2]

• Helianthus nuttallii subsp. nuttallii. Canada, western United States.
• Helianthus nuttallii subsp. parishii (A.Gray) Heiser (Los Angeles Sunflower). Southern California, endemic. It is an endangered subspecies thought to have been extinct since 1937, but it reappeared in southern California in 2001.
• Helianthus nuttallii subsp. rydbergii (Britton) R. Long. Central Canada, interior northwestern United States.

References

1. ^ ^{a b} Germplasm Resources Information Network: Helianthus nuttallii
2. ^ ^{a b} Jepson Flora: Helianthus nuttallii
3. ^ Plants of British Columbia: Helianthus nuttallii