Syn.: Helianthus angustifolius subsp. nuttallii Anashch.
Family: Asteraceae Bercht. et J. Presl
Distribution: North American species found from south of Canada to California and New Mexico. It does not reach the east of US. In its region it is divided into 3 subspecies.
Ecology: Grows in wet to marshy meadows, close to water in elevations from (300–)1200 to 2700 m. Blooms from late summer until autumn. H. n. subsp. parishii is found in California and subsp. rydbergii in the northeast area. It can become invasive.
Description: Perennial herb, stems 100–400 cm tall, erect, single or somewhat branched. Leaves have short stalks, lower ones opposite, upper ones alternate, lanceolate to linear, sand-paper texture, 4–20 × 0.8–4 cm, smooth to toothed edges. Flowers single or 2–6, terminal, bracts 30–38, lanceolate to linear, 8–16 × 1.5–3 mm, ray florets 10–21, 20–25 mm long, yellow; disc florets about 60, 5–7 mm long, yellow. Fruit is an achene resembling a sunflower seed, pappus small, deciduous scales.
Note: Native American genus Helianthus includes more than 50 species found in North America and Mexico. Several species had been spread to other parts of the globe.
These images were taken in Canada, Alberta, Calgary, Confluence Park (August 29, 2013).
