204 GRAMINEAE. 
8. Poa praténsis L. Kentucky Blue-grass. June Grass. (Fig. 466.) 
Poa pratensis I,. Sp. Pl. 67. 1753. 
ie aad var. angustifolia Kunth, Enum. 1: 353. 
Glabrous, culms 1°-4° tall, from long running 
rootstocks, erect, simple, smooth. Sheaths often 
longer than the internodes; ligule 3¢’’ long or less, 
truncate; leaves smooth or rough, 1%4//-3/’ wide, 
those of the culm 2’-6’ in length, the basal much 
longer; panicle 214’-8’ in length, usually pyram- 
idal, the branches spreading or ascending, some- 
times flexuous, 1-3’ long, divided and spikelet- 
bearing above the middle; spikelets 3-5-flowered, 
2//-2'4/’ long, exceeding their pedicels; scales 
acute, the lower unequal, glabrous, rough on 
the keel, the lower 1-nerved, the upper 3-nerved; 
flowering scales 114’’ long, webbed at the base, 5- 
nerved, the marginal nerves and midnerve silky- 
pubescent below, the intermediate ones naked. 
In meadows, fields and woods, almost throughout North America. Widely cultivated for hay 
and pasture. Alsoin Europe and Asia. In North America probably indigenous only in the northern 
and mountainous regions. Variable. June-Aug. 
g. Poa pseudoprateénsis Scribn. & Ryd. 
Prairie Meadow-grass. (Fig. 467.) 
Culms 1°-2%° tall, erect, simple, smooth and 
glabrous. Sheaths shorter than the internodes, 
smooth or slightly rough; ligule 2’ long, acute, 
decurrent; leaves 1//-3/’ wide, smooth beneath, a 
little rough above and on the margins, those of 
the culm 1/-314’ long, the basal 6’—10’ in length; 
panicle 2/-5’ long, open, the branches spreading 
or ascending, 1/-2’ long; spikelets 3-5-flowered, 
3//-4’’ long, exceeding their pedicels; lower scales 
nearly equal, acute, 3-nerved; flowering scales 
acutish, about 14’ long, rough above, 5-nerved, 
pubescent between the nerves below, the marginal 
nerves and midnerve silky-pubescent about half 
their length. 
Manitoba and Assiniboia to Nebraska and Colorado. 
10. Poa trivialis L. Roughish Meadow-grass. (Fig. 468.) 
Poa trivialis \,. Sp. Pl. 67.1753. 
Culms 1°—3° tall, usually more or less decumbent 
at the base, simple, smooth or slightly scabrous. 
Sheaths usually shorter than the internodes, rough; 
ligule 2’/-3/’ long, acutish; leaves 2’-7’ in length, 
1//-2// wide, generally very rough; panicle 4’—6’ long, 
open, the branches usually spreading or ascending, 
1/-2/ long; spikelets 2- or sometimes 3-flowered, 114’’ 
long, exceeding their pedicels; scales acute, the empty 
basal ones rough on the keel, the lower 1-nerved, 
shorter than the 3-nerved upper; flowering scales 1//— 
114’’ long, webbed at the base, 5-nerved, the mid- 
nerve silky-pubescent below, the lateral nerves 
naked, the intermediate ones prominent. 
In meadows and waste places, New Brunswick to 
Michigan and Virginia. Naturalized from Europe. 
June-Aug. 
