Burke: Symphyotrichum pilosum vs. Symphyotrichum chilense

	Symphyotrichum pilosum	Symphyotrichum chilense
	hairy aster	common California aster, Pacific aster
Habit		Fibrous-rooted perennial from a rhizome or branched base, the stems 2-10 dm. tall, pubescent at least above.
Leaves		Lower leaves oblanceolate, petiolate, entire, pubescent, early-deciduous; middle and upper leaves linear to obovate or oval, sessile, entire, usually pubescent, 2-10 cm. long and 2-20 mm. wide.
Flowers		Heads few to many in an open inflorescence, with a few erect, pointed, linear bracts below the heads; involucre 5-7 mm. high, the bracts imbricate, papery below and green above, the outer rounded, the inner pointed; disk flowers numerous, yellow; ray flowers 15-40, pistillate, blue or pinkish, 7-15 mm. long; pappus of numerous capillary bristles.
Fruits		Fruit an achene.

	Symphyotrichum pilosum	Symphyotrichum chilense
Flowering time	August-October	July-October
Habitat	River cobbles, gravel, disturbed ground, and railroads.	Coastal, bluffs, grasslands, open slopes, salt marsh margins, and disturbed ground.
Distribution	Occurring in scattered locations east of the Cascades crest in Washington; southwestern British Columbia to Washington, otherwise native from the U.S. Great Plains east to the Atlantic Coast. [WildflowerSearch map] [BONAP county map]	Occurring west of the Cascades crest in Washington; British Columbia to California. [WildflowerSearch map] [BONAP county map]
Origin	Introduced from central and eastern North America	Native
Conservation status	Not of concern	Not of concern
Sibling taxa	S. ×amethystinum, S. ascendens, S. boreale, S. bracteolatum, S. campestre, S. chilense, S. ciliatum, S. ×columbianum, S. ericoides, S. foliaceum, S. frondosum, S. hallii, S. jessicae, S. laeve, S. lanceolatum, S. novae-angliae, S. spathulatum, S. subspicatum	S. ×amethystinum, S. ascendens, S. boreale, S. bracteolatum, S. campestre, S. ciliatum, S. ×columbianum, S. ericoides, S. foliaceum, S. frondosum, S. hallii, S. jessicae, S. laeve, S. lanceolatum, S. novae-angliae, S. pilosum, S. spathulatum, S. subspicatum
Subordinate taxa	S. pilosum var. pilosum
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

Symphyotrichum pilosum

Symphyotrichum chilense

hairy aster

common California aster, Pacific aster

Habit

Fibrous-rooted perennial from a rhizome or branched base, the stems 2-10 dm. tall, pubescent at least above.

Leaves

Lower leaves oblanceolate, petiolate, entire, pubescent, early-deciduous; middle and upper leaves linear to obovate or oval, sessile, entire, usually pubescent, 2-10 cm. long and 2-20 mm. wide.

Flowers

Heads few to many in an open inflorescence, with a few erect, pointed, linear bracts below the heads;

involucre 5-7 mm. high, the bracts imbricate, papery below and green above, the outer rounded, the inner pointed;

disk flowers numerous, yellow;

ray flowers 15-40, pistillate, blue or pinkish, 7-15 mm. long;

pappus of numerous capillary bristles.

Fruits

Fruit an achene.

Symphyotrichum pilosum

Symphyotrichum chilense

Flowering time

August-October

July-October

Habitat

River cobbles, gravel, disturbed ground, and railroads.

Coastal, bluffs, grasslands, open slopes, salt marsh margins, and disturbed ground.

Distribution

Occurring in scattered locations east of the Cascades crest in Washington; southwestern British Columbia to Washington, otherwise native from the U.S. Great Plains east to the Atlantic Coast.

[WildflowerSearch map]

[BONAP county map]