OregonFlora: Chaenactis douglasii

	Chaenactis douglasii
	Douglas' dusty maidens, hoary false yarrow
Habit	Plants biennial or perennial, 5–60 cm.
Stems	erect, floccose-tomentose, often glandular-puberulent distally.
Leaves	basal and cauline, narrowly lanceolate to oblanceolate, elliptic, or linear, 1–12 cm, 2-pinnately lobed; secondary lobes becoming inrolled and disc-like with age; surfaces tomentose, petiolate.
Involucres	obconic or campanulate, 8–15 mm.
Disc florets	corollas 5–8 mm, white, pink, or pale yellow, glabrous or glandular-puberulent; outer radially symmetric.
Phyllaries	in 2–5 unequal series, linear to narrowly elliptic or oblanceolate; surfaces cobwebby to woolly, stipitate-glandular.
Fruits	5–8 mm; surfaces strigose or glandular-puberulent; pappi in 3–4 series of unequal scales.
Heads	erect, peduncled.
2n	=12, 24, 36.

	Chaenactis douglasii
Distribution	[WildflowerSearch map] [BONAP county map]
Discussion	Woodlands, shrublands, grasslands, dry hillsides, ridge tops, riverbanks, rock outcrops, disturbed areas. Flowering Apr–Sep. 0–2300 m. BR, BW, Casc, Col, ECas, Lava, Owy, Sisk. CA, ID, NV, WA; north to British Columbia, northeast to Alberta, east to SD, southeast to NM. Native. Chromosome studies by Mooring (1980) show that this species varies from diploid to hexaploid, with intermediate numbers resulting from hybridization. As a result, morphological differences at the diploid level become mixed into a morphological continuum among the polyploids.
Source	Flora of Oregon, volume 2, page 219 Kenton Chambers
Sibling taxa	C. alpina, C. cusickii, C. macrantha, C. nevii, C. stevioides, C. suffrutescens, C. xantiana
Synonyms	Chaenactis douglasii var. douglasii, Chaenactis douglasii var. glandulosa, Chaenactis douglasii var. montana, Chaenactis rubricaulis
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria, Turner Photog. WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Chaenactis douglasii

Douglas' dusty maidens, hoary false yarrow

Habit

Plants biennial or perennial, 5–60 cm.

Stems

erect, floccose-tomentose, often glandular-puberulent distally.

Leaves

basal and cauline, narrowly lanceolate to oblanceolate, elliptic, or linear, 1–12 cm, 2-pinnately lobed; secondary lobes becoming inrolled and disc-like with age;

surfaces tomentose, petiolate.

Involucres

obconic or campanulate, 8–15 mm.

Disc florets

corollas 5–8 mm, white, pink, or pale yellow, glabrous or glandular-puberulent; outer radially symmetric.

Phyllaries

in 2–5 unequal series, linear to narrowly elliptic or oblanceolate;

surfaces cobwebby to woolly, stipitate-glandular.

Fruits

5–8 mm;

surfaces strigose or glandular-puberulent;

pappi in 3–4 series of unequal scales.

Heads

erect, peduncled.

=12, 24, 36.

Chaenactis douglasii

Distribution

[WildflowerSearch map]

[BONAP county map]

Discussion

Woodlands, shrublands, grasslands, dry hillsides, ridge tops, riverbanks, rock outcrops, disturbed areas. Flowering Apr–Sep. 0–2300 m. BR, BW, Casc, Col, ECas, Lava, Owy, Sisk. CA, ID, NV, WA; north to British Columbia, northeast to Alberta, east to SD, southeast to NM. Native.

Chromosome studies by Mooring (1980) show that this species varies from diploid to hexaploid, with intermediate numbers resulting from hybridization. As a result, morphological differences at the diploid level become mixed into a morphological continuum among the polyploids.

Source

Flora of Oregon, volume 2, page 219
Kenton Chambers

Sibling taxa