132 



GRAMINEAE (GRASS FAMILY) 



. 1. A. alba. 

 (1) A. alba, v. maritima. 



flowered, branches solitary, much divided ; spikelets 1.5 mm. long ; the obtuse 

 or erose glumes about | as long as the equal glabrous obtuse lemma and palea. 

 (S. serotinus Gray.) Bogs and wet sandy soil, Me. to N. J. and Mich. Aug., 

 Sept. FIG. 102. 



32. AGR6STIS L. BENT GRASS 



Spikelets 1-flowered ; glumes subequal and acute, longer than the broad ob- 

 tuse lemma which is awnless or dorsally awned ; palea hyaline, shorter than the 

 lemma, or obsolete ; grain loosely inclosed in the lemma. Annuals or peren- 

 nials with usually flat scabrous leaves, membranaceous ligules and open or con- 

 tracted panicles. (Name from dyp6s, afield, the place of growth.) 



Palea at least one-half as long as the lemma, 2-nerved. 



Culms erect or decumbent at base 



Culms prostrate, rooting at the nodes 



Palea minute and nerveless or wanting. 



Awn long and very delicate 2. A. Elliottiana. 



Awn short or none. 



Panicle diffuse, branches long and capillary 3. A. hyemalis. 



Panicle spreading but not diffuse. 



Lemma awnless 4. A. perennans. 



Lemma awned. 



Spikelets 2 mm. long 5. A. canina. 



Spikelets 3 mm. long 6. A, borealis. 



1. A. alba L. (FIORIN or WHITE B., RED TOP.) Rootstocks creeping or sto- 

 loniferous ; culms 3-10 dm. high, often decumbent at base ; leaves flat, stiff 

 and upright to lax and spreading, the ligule 4-5 mm. long ; panicle 5-30 cm. 



long, contracted after flowering, greenish, purplish, or brown- 

 ish, the branches slightly rough ; lemma nearly equaling the 

 glumes, 3-nerved, rarely short-awned, the palea J-f as long. 

 Meadows and fields ; a valuable grass naturalized from Eu. 

 and native northw. and westw. Var. VULGARIS (With.) 

 Thurb. (RED TOP, HERD'S GRASS of Pa., etc.) Culms lower, 

 more slender, with narrow leaves ; panicle smaller and more 

 divaricate, not contracted after flowering ; ligule short and 

 truncate. (A. vulgaris With.) Dry knolls and hills. (Nat. 

 from Eu. and cultivated, also perhaps indigenous.) FIG. 103. 

 One form (A. stolonifera auth., not L.) is cultivated as a 

 lawn grass under the name CREEPING BENT. A teratological 

 form (due to the presence of nematodes in the abortive 

 ovaries) with floral parts elongated (A sylvatica L.), occurs 

 in N. E. 



Var. aristata Gray. Culms slender and strict, with small 

 open panicle ; lemma awned from near the base. (A. stricta 

 Willd.) Open ground, Me. to Va. In habit resembling 

 A. canina, with which it is often confused. 



Var. maritima (Lam.) G. F. W. Mey. Culms densely 



tufted, prostrate, rooting at the nodes; leaves mostly short and appressed ; 



panicle contracted, dense, about 1 dm. long. (A. coarctata Ehrh.) Brackish 



meadows or wet sands along the coast, Me. to Del. (Eu.) 



2. A. Elliottiana Schultes. Culms delicate, 1-4 dm. high ; leaves very slen- 

 der ; panicle open, weak, and drooping ; glumes nearly equal, roughish on the 

 keel and margins, the lemma shorter, with 2 minute bristles at the truncate apex; 

 awn 5 mm. long; palea minute. In dry soil, Mo. to Ky., Tenn., and S. C. 

 May- July. 



3. A. hyemalis (Walt.) BSP. (HAIR GRASS.) Culms very slender, erect, 

 3-6 dm. high ; leaves short and narrow, the tufted basal ones soon involute, the 

 upper 2-7 cm. long, less than 2 mm. wide; panicle purplish, the whorled 

 scabrous branches spikelet-bearing at the ends ; spikelets 1.5-2 mm. long ; lemma 

 awnless or rarely short-awned on the back, shorter than the rather unequal 

 very acute glumes; palea obsolete. (A. scabra Willd.) Dry or moist open 

 woodland, sandy low land, rocks, etc., common. June- Aug. A form with 



103. A. alba, v. vulg. 

 Panicle x %. 

 Spikelet x 3. 



