202 



GRAMINEAE. 



2. Poa Chapmaniana Scribn. Chapman's Spear-grass. (Fig. 460.) 



Fl. S. States, 562. 1860. Not 

 Bull. Torr. Club, 21: 38. 



Poa cristata Chapm. 



Walt. 1788. 

 Poa Chapmaniana Scribn 



1894- 



Culms 3 / -6 / tall, erect from an annual root, 

 simple, rigid, smooth and glabrous. Sheaths 

 tight, mostly at the base of the culm; ligule y^ f/ 

 long, truncate; leaves J^'-i'long, J^" wide or less, 

 smooth; panicle i / -2 / in length, the branches 

 usually erect, sometimes spreading or ascending, 

 ^ f long or less, naked at the base; spikelets 3-7- 

 flowered, lX // - I X // l n g; lower scales about 

 equal, 3-nerved, acute; flowering scales webbed at 

 the base, obtuse, 3-nerved. sometimes with two ad- 

 ditional obscure nerves, the prominent ones some- 

 times pilose for three-fourths their length. 



In dry soil, Kentucky and Tennessee to Florida and 

 Alabama. April-May. 





3. Poa compressa 



. Wire-grass. Flat-stemmed Meadow-grass. English 

 Blue-grass. (Fig. 461.) 



Poa compressa L. Sp. PI. 69. 1753. 



Pale bluish-green, glabrous, culms 6 / -2 tall, decum- 

 bent at the base, from long horizontal rootstocks, smooth, 

 much flattened. Sheaths loose, flattened, shorter than 

 the internodes; ligule y z fr long; leaves \ f -\' long, about 

 i" wide, smooth beneath, rough above; panicle usu- 

 ally contracted, the branches erect or ascending, \ f 

 long or less, spikelet-bearing nearly to the base; spike- 

 lets 3-9-flowered, i^ // -3 // long; lower scales acute, 3- 

 nerved; flowering scales i // -i^ // long, obscurely 3- 

 nerved, the nerves sparingly pubescent toward the 

 base. 



Waste places and cultivated grounds and woods almost 

 throughout North America. Ascends to 2100 ft. in Virginia. 

 Naturalized from Europe. Native also of Asia. Varies from 

 weak and slender to quite stiff. June-Aug. 



4. Poa abbreviata R. Br. Low Spear- 

 grass. (Fig. 462.) 



Poa abbreviata R. Br. Bot. App. Parry's Voy. 287. 



Culms 6' tall or less, erect, simple, smooth and 

 glabrous. Sheaths and leaves crowded at the base 

 of the culm; ligule %" long; leaves % f -i f long, 

 y-i" wide; panicle contracted, J^'-i' long, branches 

 very short and erect; spikelets 3-5-flowered, 2#" 

 long; lower scales acute, smooth and glabrous; 

 flowering scales about \W long, obtuse, strongly 

 pubescent all over, the intermediate nerves very 

 obscure. 



Arctic America from Greenland and Labrador to the 

 Pacific. Summer. 



