Burke: Eurybia sibirica vs. Eurybia radulina

	Eurybia sibirica	Eurybia radulina
	arctic aster	rough-leaved aster
Habit	Rhizomatous perennial usually about 1 dm. tall; the stem and lower surfaces of the leaves sparsely to copiously short-hairy.	Herbaceous perennial from well-developed rhizomes, 1-7 dm. tall, the stem and lower surface of the leaves with short hairs.
Leaves	Leaves firm, entire or with a few short teeth, mostly sessile, 2.5-8 cm. long and 4-25 mm. wide, the lowermost reduced.	Leaves firm, usually sharply toothed, broadly oblanceolate or broader, the largest ones, found a little above the base of the stem, up to 10 cm long and 4 cm. wide; lowest leaves strongly reduced, middle and upper leaves gradually reduced, the stem appearing leafy.
Flowers	Heads solitary, or few in a compact inflorescence; involucre 6-9 mm. high, the bracts imbricate in several series, loose, papery below, green-tipped and purple-margined; rays 12-23, purple, 8-12 mm. long; pappus bristles of various lengths; disk corollas yellow, 5.5-7.6 mm. long, the tube about equal to the slender limb.	Heads several in a flat-topped inflorescence; involucre imbricate in several series, the bracts green-tipped, often purple-margined; rays lavender to white, 8-12 mm. long; disk corollas yellow, 7-8 mm. long, the tube longer than the slender limb; pappus bristles of various lengths.
Fruits	Achene	Achene.

	Eurybia sibirica	Eurybia radulina
Identification notes		The large, sharply-toothed leaves are distinctive.
Flowering time	July-September	July-September
Habitat	Rocky outcroppings, open slopes, and meadows in the subalpine and alpine.	Rocky outcroppings, forest edges and openings at low to middle elevations.
Distribution	Occurring west of the Cascades crest in Washington; Alaska to Washington, east to Northwest Territory, Nunavut, Alberta, Idaho, and Montana. [WildflowerSearch map] [BONAP county map]	Occurring east of the Cascades crest and in the Columbia River Gorge in Washington; British Columbia to California. [WildflowerSearch map] [BONAP county map]
Origin	Native	Native
Conservation status	Review Group 1 in Washington (WANHP)	Not of concern
Sibling taxa	E. conspicua, E. integrifolia, E. merita, E. radulina	E. conspicua, E. integrifolia, E. merita, E. sibirica
Web links	Local floras: BC, WA Local Web sites: Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Eurybia radulina

arctic aster

rough-leaved aster

Habit

Rhizomatous perennial usually about 1 dm. tall; the stem and lower surfaces of the leaves sparsely to copiously short-hairy.

Herbaceous perennial from well-developed rhizomes, 1-7 dm. tall, the stem and lower surface of the leaves with short hairs.

Leaves

Leaves firm, entire or with a few short teeth, mostly sessile, 2.5-8 cm. long and 4-25 mm. wide, the lowermost reduced.

Leaves firm, usually sharply toothed, broadly oblanceolate or broader, the largest ones, found a little above the base of the stem, up to 10 cm long and 4 cm. wide; lowest leaves strongly reduced, middle and upper leaves gradually reduced, the stem appearing leafy.

Flowers

Heads solitary, or few in a compact inflorescence;

involucre 6-9 mm. high, the bracts imbricate in several series, loose, papery below, green-tipped and purple-margined;

rays 12-23, purple, 8-12 mm. long;

pappus bristles of various lengths; disk corollas yellow, 5.5-7.6 mm. long, the tube about equal to the slender limb.

Heads several in a flat-topped inflorescence;

involucre imbricate in several series, the bracts green-tipped, often purple-margined;

rays lavender to white, 8-12 mm. long; disk corollas yellow, 7-8 mm. long, the tube longer than the slender limb;

pappus bristles of various lengths.

Fruits

Achene

Achene.