204 



A TEXT-BOOK OF GRASSES 



blades and an erect open often reddish panicle usually 4 

 to 8 inches long, with verticillate lower branches. A 

 smaller form, Rhode Island bent (A. alba vulgaris), with 

 finer foliage and a smaller more open panicle, is often 

 used for lawns. Another form of Agrostis alba with 

 creeping stems and narrow panicle is used for lawns 

 under the name of creeping bent. 



Agrostis alba L. (Fig. 40) Redtop. Peren- 

 nial; culms erect from a more or less decum- 

 bent base bearing rhizomes, smooth, 1 to 4 feet 

 high; sheaths smooth; hgule membranaceous, 

 pointed, more or less lacerate, as much as 6 

 mm. long; blades flat, 2 inches to as much as 

 a foot long, scabrous on both surfaces, strongly- 

 nerved, acuminate, usually rather stiffly up- 

 right; panicle 2 to 12 inches long, open at 

 anthesis but usually more or less contracted 

 in fruit, the branches in whorls, some naked 

 below, others short and spikelet-bearing at 

 base; glumes 2 to 3 mm. long, lanceolate, 

 pointed, scabrous on the keel, the lemma thin, 

 a little shorter than the glumes, the palea half 

 to two-thirds as long as the lemma. The color 

 of the panicle varies from greenish to purple or 

 brown. This grass has escaped from cultiva- 

 tion or has been introduced over a large part of 

 the United States. In the western mountains 

 the species is doubtfully native. This grass is 

 known by the name of herd's-grass in some 

 localities, especially in Pennsylvania. In Eng- 

 land it is called florin. 



Agrostis alba vulgaris (With.) Thurb. Rhode 

 Island bent. Differs from the preceding in the 

 smaller size, more delicate 

 culms and foliage, smaller 

 and especially more open 

 and fewer-flowered panicle, 



Fig. 40. Agrostis alba. Inflorescence and ,,. . , x j • 



rhizomes, XH: spikelet, X5. ttiis not contracted m 



i 



