Burke: Poa cusickii vs. Poa macrantha

	Poa cusickii	Poa macrantha
	Cusick's bluegrass	sand-dune blue grass
Habit	Smooth, strongly tufted perennial, the culms hollow, 2-4 dm. tall.	Strongly rhizomatous, dioecious perennial, the culms hollow, glabrous, 2-4 dm. tall.
Leaves	Sheaths closed about half their length; ligules 1-3 mm. long, acute, jagged, glabrous; blades of the fertile stems 1-3.5 mm. broad, flat; blades of the sterile stems 0.5-1 mm. broad, involute, often 1-2 dm. long; all blades with prow-like tips.	Sheaths glabrous, open most of their length, but closed as least for the lower 2-3 cm.; ligules 1-1.5 mm. long, thick, strongly pubescent, truncate, highest on the sides; blades stiff and involute, in dense basal tufts, up to 3 mm. broad, 5-12 cm. long, the tips only slightly prow-like.
Flowers	Inflorescence a compact, ovoid panicle 2-6 cm. long, greenish or purplish; spikelets 3- to 5-flowered, 5-8 mm. long; flowers usually pistillate, the anthers vestigial or wanting, but occasionally the plants staminate- or perfect-flowered; glumes subequal, 3-nerved, 3.5-5 mm. long, shorter than the first floret; lemmas keeled, 5-nerved, 4.5-6 mm. long, pubescent; paleas slightly shorter than the lemmas, 2-keeled.	Inflorescence a compact panicle 4-12 cm. long, the branches short, stiff and ascending; spikelets 4- to 6-flowered, occasionally bulbiferous; glumes subequal, about 9 mm. long, 5-nerved, keeled; lemmas about 9 mm. long, 7- to 11-nerved, pubescent on the keel and marginal nerves, the rachilla also pubescent with soft, straight hairs; staminate flowers with anthers 3.5 mm. long, pistillate flowers with vestigial stamens.

	Poa cusickii	Poa macrantha
Flowering time	May-August	April-July
Habitat	Sagebrush plains to alpine meadows and ridges.	Sand dunes along the marine coast.
Distribution	Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Saskatchewan and Colorado. [WildflowerSearch map] [BONAP county map]	Occurring west of the Cascades crest along the coast in Washington; southern Alaska to California. [WildflowerSearch map] [BONAP county map]
Origin	Native	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. 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	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. 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. cusickii ssp. cusickii, P. cusickii ssp. epilis, P. cusickii ssp. pallida, P. cusickii ssp. purpurascens
Web links	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	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 macrantha

Cusick's bluegrass

sand-dune blue grass

Habit

Smooth, strongly tufted perennial, the culms hollow, 2-4 dm. tall.

Strongly rhizomatous, dioecious perennial, the culms hollow, glabrous, 2-4 dm. tall.

Leaves

Sheaths closed about half their length;

ligules 1-3 mm. long, acute, jagged, glabrous;

blades of the fertile stems 1-3.5 mm. broad, flat;

blades of the sterile stems 0.5-1 mm. broad, involute, often 1-2 dm. long; all blades with prow-like tips.

Sheaths glabrous, open most of their length, but closed as least for the lower 2-3 cm.;

ligules 1-1.5 mm. long, thick, strongly pubescent, truncate, highest on the sides;

blades stiff and involute, in dense basal tufts, up to 3 mm. broad, 5-12 cm. long, the tips only slightly prow-like.

Flowers

Inflorescence a compact, ovoid panicle 2-6 cm. long, greenish or purplish;

spikelets 3- to 5-flowered, 5-8 mm. long;

flowers usually pistillate, the anthers vestigial or wanting, but occasionally the plants staminate- or perfect-flowered;

glumes subequal, 3-nerved, 3.5-5 mm. long, shorter than the first floret;

lemmas keeled, 5-nerved, 4.5-6 mm. long, pubescent;

paleas slightly shorter than the lemmas, 2-keeled.

Inflorescence a compact panicle 4-12 cm. long, the branches short, stiff and ascending;

spikelets 4- to 6-flowered, occasionally bulbiferous;

glumes subequal, about 9 mm. long, 5-nerved, keeled;

lemmas about 9 mm. long, 7- to 11-nerved, pubescent on the keel and marginal nerves, the rachilla also pubescent with soft, straight hairs; staminate flowers with anthers 3.5 mm. long, pistillate flowers with vestigial stamens.