Burke: Poa pratensis vs. Poa confinis

	Poa pratensis	Poa confinis
	Kentucky bluegrass	coastline blue grass
Habit	Strongly rhizomatous perennial, the culms hollow, glabrous, 4-10 dm. tall.	Strongly rhizomatous, dioecious perennial, mostly glabrous, the culms 10-35 cm. tall with a decumbent base.
Leaves	Sheaths closed about half their length; ligules 1-1.5 mm. long, truncate, usually entire; blades flat, numerous, 2-4 mm. broad, the tips strongly prow-shaped.	Leaves basally tufted, the sheaths open for over half their length, the blades involute, reaching to the panicles, scarcely 2 mm. broad, the tips only slightly prow-like; ligules membranous, acute, 0.8-2 mm. long, entire, pubescent.
Flowers	Inflorescence a moderately loose panicle 3-10 cm. long, the branches slightly ascending, the lower ones 3-5 per node; spikelets 3- to 5-flowered; glumes 2.5 and 3 mm. long, strongly keeled; lemmas about 3.5 mm. long, strongly keeled, cobwebby at the base; palea subequal to the lemma, 2-keeled.	Inflorescence a compact panicle, 1.5-3.5 cm. long, the branches erect, tawny to purplish; spikelets 3-4 flowers, the rachilla usually with a terminal rudiment; glumes 3-nerved, about equal in width, the first 2.5-3 mm. long, the second 3-4 mm. long; lemmas strongly keeled, faintly 5-nerved, glabrous, unawned.
Fruits		Utricle

	Poa pratensis	Poa confinis
Flowering time	April-October	May-June
Habitat	Moist, distrurbed areas from the coast to middle elevations.	Coastal sand dunes.
Distribution	Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast: circumboreal. [WildflowerSearch map] [BONAP county map]	Occurring west of the Cascades crest in Washington along the coast; British Columbia to California. [BONAP county map]
Origin	Both native and introduced	Native
Conservation status	Not of concern	Not of concern
Sibling taxa	P. alpina, P. annua, P. arctica, P. bolanderi, P. bulbosa, P. compressa, P. confinis, P. curtifolia, P. cusickii, P. fendleriana, P. glauca, P. howellii, P. infirma, P. interior, P. laxiflora, P. leibergii, P. leptocoma, P. lettermanii, P. macrantha, P. marcida, P. ×multnomae, P. nemoralis, P. nervosa, P. palustris, P. paucispicula, P. secunda, P. stenantha, P. suksdorfii, P. trivialis, P. unilateralis, P. wheeleri	P. alpina, P. annua, P. arctica, P. bolanderi, P. bulbosa, P. compressa, P. curtifolia, P. cusickii, P. fendleriana, P. glauca, P. howellii, P. infirma, P. interior, P. laxiflora, P. leibergii, P. leptocoma, P. lettermanii, P. macrantha, P. marcida, P. ×multnomae, P. nemoralis, P. nervosa, P. palustris, P. paucispicula, P. pratensis, P. secunda, P. stenantha, P. suksdorfii, P. trivialis, P. unilateralis, P. wheeleri
Subordinate taxa	P. pratensis ssp. angustifolia, P. pratensis ssp. irrigata, P. pratensis ssp. pratensis
Web links	Local floras: BC, OR, 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

Poa pratensis

Poa confinis

Kentucky bluegrass

coastline blue grass

Habit

Strongly rhizomatous perennial, the culms hollow, glabrous, 4-10 dm. tall.

Strongly rhizomatous, dioecious perennial, mostly glabrous, the culms 10-35 cm. tall with a decumbent base.

Leaves

Sheaths closed about half their length;

ligules 1-1.5 mm. long, truncate, usually entire;

blades flat, numerous, 2-4 mm. broad, the tips strongly prow-shaped.

Leaves basally tufted, the sheaths open for over half their length, the blades involute, reaching to the panicles, scarcely 2 mm. broad, the tips only slightly prow-like;

ligules membranous, acute, 0.8-2 mm. long, entire, pubescent.

Flowers

Inflorescence a moderately loose panicle 3-10 cm. long, the branches slightly ascending, the lower ones 3-5 per node;

spikelets 3- to 5-flowered;

glumes 2.5 and 3 mm. long, strongly keeled;

lemmas about 3.5 mm. long, strongly keeled, cobwebby at the base;

palea subequal to the lemma, 2-keeled.

Inflorescence a compact panicle, 1.5-3.5 cm. long, the branches erect, tawny to purplish;

spikelets 3-4 flowers, the rachilla usually with a terminal rudiment;

glumes 3-nerved, about equal in width, the first 2.5-3 mm. long, the second 3-4 mm. long;

lemmas strongly keeled, faintly 5-nerved, glabrous, unawned.

Fruits