132 



GKAMINEAE (GRASS FAMILY) 



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

 or erose glumes about i 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 l-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 scabrotis leaves, membranaceous ligules and open or con- 

 tracted panicles. (Name from dypos, 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 verj- delicate 



Awn short or none. 

 Panicle diffuse, branches long and capillary . 

 Panicle spreading but not diffuse. 



Lemma awnless . 



Lemma awned. 



Spikelets 2 mm. long 



Spikelets 3 mm. long 



. 1. A. alha. 

 (1) A. alha, v. maritima. 



2. A. EUiottiana. 



3. A. hyemalis. 



4. A. perennans. 



5. A. canina. 



6. A. borealis. 



1. A. alba L. (Fiorix or White B., Red Top.) Bootstocks creeping or sto- 

 loniferous ; culms 3-10 dm. high, often decumbent at base ; leaves fiat, 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 ^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. (Xat. 

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

 — One form {A. stolonifera autii., not L.) is cultivated as a 

 lawn grass under the name Creepi^tg 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. arista ta Gray. Culms slender and strict, with small 

 open panicle ; lemma aioned 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 (I^am.) 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 YA\x\\.) — Brackish 



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



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

 der ; panicle open, xceak, and drooping ; glumes nearlj'- equal, rougliish 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, 

 3-0 dm. liigli ; leaves short and narrow, the tufted basal ones soon involute, the 

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

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

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

 very acute glumes; paU-a obsolete. (A: scahra Willd.) — Dry Or moist open 

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



103. A. alba, v. vulg, 

 Panicle x y^. 

 Spikelet x 3. 



