G14 CLXl. GRAMINE^. Poa 



41. POA. 



Gr. TToa, the general name <br grasses or herbage. 



Spikelets compressed, ovate, obloug or linear, many-flowered (3 — ■ 

 20) ; glumes 2, shorter than ttie lower flowers ; paleas subequal, awu- 

 less, often with an arachnoid web at base, bifid-toothed, the lower one 

 herbaceous, scarious on the margin ; scales ovate, acute, smooth. 

 * Flowers webbed at base. 



1. P. PRATENsis. Spear Grass. 



St. terete, smooth, 1 — 2f high ; Ivs. carinate, linear, abruptly acute, radi- 

 cal ones very long and numerous, cauline shorter than the veined, smooth 

 sheaths ; slip, short, truncate ; panicle difluse, branches 3 — 5 together in hall- 

 whorls ; spikelets ovate, acute, with about 4, acute flowers ; glumes lanceolate, 

 rather acuminate. — % An excellent grass both for hay and pasturage, very 

 abundant. May, June. Varies much in luxuriance according to the soil. 



2. P. TRiviALis. (P. stolonifera. Muhl.) Roughish Meadow Grass. 



Sis. sometimes stoloniierous at base, roughish backwards, 2 — 3f high ; 

 ivs. lance-linear, acute, rough-edged, lower ones very long, cauline as long as 

 the roughish sheaths, with long, acuminate stipules ; panidc difJuse, expanding, 

 scabrous, branches 4 — 5 together in hall-whorls; spikelets oblong-ovate, 2 — 3- 

 flowered. — %. A grass equally common and valuable with the last, JN". States, 

 June, July. 



3. P. coMPRESSA. Blue Ch-ass. 



St. decumbent and rooting at base, much compressed, smooth, striate, 12 

 — 18' high; lis. linear, carinate, veined, smooth, short, bluish-green; sheaths 

 smooth, rather loose, with a sliort, obtuse stipule ; panicle contracted, somewhat 

 secund, branches scabrous, in 2s and 3s; spikelets ovate-oblong, 3 — 6-"flowered, 

 subsessile. — % Less abundant tlian the last, forming tufts in moist places, Free 

 States. June. 



4. P. SEROTiNA. Erhr. (P. palustris. MiM.) Meadow Red-top. 



St. erect, 2 — 3f high; Ivs. liat, narrow-linear, smooth, 10 — 15' long; slip. 

 long, lacerated ; panicle diffuse, somewhat secund, 6 — 10' long, branches in 

 half-whorls ; spikelets ovate-lanceolate, 2 — 3-flowered ; fls. but little webbed at 

 base, yellow at the tip, obscurely 5-veined. — 1\. Common in wet meadows, Free 

 States. June. 



5. P. PUNGENs. Torr. (P. flexuosa. Muhl.) 



St. compressed, 1 — 2f high ; Ivs. ot the stem about 2, flat, oblong, lanceo- 

 late, cuspidate and pungent, lower about 1' long, upper minute, root Ivs. long 

 and narrow, all erect, keeled and pungent at the point ; slip, truncate, lacerate; 

 sheaths nearly as long as the nodes; panicle small, racemose at apex, branches 

 in half-whorls, capillary; spikelets ovate, 3 — 4-flowered ; fls. rather obtuse, 

 webbed ; glumes smooth, upper acute ; sty. doubly plumose, white. — 'Zj. Middle 

 and Western States. April. 



6. P. LAXA. Hoenke. (P. alpina. Torr.) 



St. caespitose, 6 — 8' high ; lis. linear, acute, smooth; slip, lanceolate -jpan. 

 1 — 2' long, contracted, nodding, branches mostly in pairs, smooth, fiexuous ; 

 spikelets 2^" long, ovate, 3-fldwered ; fls. often purple, acute, hairy, somewhat 

 webbed at base ; glume lance-ovate, slightly scabrous on the keel ; loicer palea 

 hairy below, upper rough-edged; «;i;A. violet. — Tj. Mountains and woods, N 

 Eng. ! and Mid. States. 



7. P. NEMORALis. Wood Spear Grass. 



St. slender, 2 — 3f high ; Ivs. narrow-linear, pale green, smooth as well as 

 the sheaths; slip, scarcely any; panicle 6 — 10' long, slender, nodding when in 

 fruit, branches capillary, flexuous, in 2s or 3s ; spikelets ovate, about 3-flowered, 

 the flowers spreading and at length remote, slightly webbed at base. — % A tall,' 

 rank grass, in wet, open woods, N. Eng. ! and Mid. States. July 

 * * Floiccrsfree, or not webbed at base. 



8. P. ANNUA. Annual Spear Grass. 



S/s. decumbent and rooting at the base, smooth, compressed, 3 — 8' long* 



