334 

 I 



MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



Figure 457. — Calamovilfa gigantea. Panicle, X Yi \ glumes and floret, X 5. (White, Okla.) 



20 cm. long, usually less than half as 

 broad, the branches capillary, spread- 

 ing, whorled, naked at base; spikelets 

 2 to 2.5 mm. long; glumes somewhat 

 unequal, the first shorter and nar- 

 rower; lemma about as long as the 

 second glume, scaberulous, with a 

 slender awn from below the apex, the 

 awn about twice as long as the 

 glumes; palea about as long as the 

 lemma; rachilla less than 0.5 mm. 

 long. O — Introduced at a few 

 points from Maine to Maryland; 



Ohio; Missouri; Portland, Oreg.; Eu- 

 rope. 

 2. Apera interrupts (L.) Beauv. 



(Fig. 459.) Similar to A. spica-venti; 

 panicle narrower, more condensed, in- 

 terrupted, the branches or some of 

 them floriferous from the base; awn 

 of lemma about 1 cm. long. O — 

 Introduced in Missouri (St. Louis), 

 Washington (Spokane), Oregon (Port- 

 land), Idaho (Nezperce Forest), and 

 British Columbia (Okanogan); Eu- 

 rope. 



71. AGROSTIS L. Bentgrass 



Spikelets 1-flowered, disarticulating above the glumes, the rachilla usually 

 not prolonged ; glumes equal or nearly so, acute, acuminate, or sometimes awn- 

 pointed, usually scabrous on the keel and sometimes on the back; lemma 

 obtuse, usually shorter and thinner than the glumes, mostly 3-nerved, awnless 

 or dorsally awned, often hairy on the callus; palea usually shorter than the lem- 

 ma, 2-nerved in only a few species, usually small and nerveless or obsolete. 

 Delicate to moderately tall annuals or usually perennials, with flat or some- 

 times involute, scabrous blades, and open to contracted panicles of small 

 spikelets. Type species, Agrostis stolonifera. Name from Greek agrostis, el 

 kind of grass, from agros, a field; the word agrostology is from the same root. 

 The rachilla is regularly prolonged in a few species and in occasional spikelets 

 of other species. 



Most of the species are important forage plants, either under cultivation or 

 in the mountain meadows of the Western States. The three important culti- 

 vated species are redtop, Agrostis alba, used for meadows, pastures, lawns, 

 and sports turf, Colonial bent, A. tenuis, used for pastures, lawns, and sports 

 turf, and creeping bent, A. palustris, used for lawns and golf greens. Velvet 

 bent, A. canina, is sometimes used for putting greens. Recently forms of 

 A. palustris, called Washington bent and Metropolitan bent, have come into 

 use for lawns and especially for golf greens. They are propagated by the stolons. 

 Fiorin is a name applied in England to A . palustris. 



The native species abundant enough to be of importance as forage plants are 

 A. exarata, throughout the western part of the United States, A. oregonensis 

 in Oregon, and A. variabilis in alpine regions of the Northwest. 



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



