590 



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



Kuntze.) — Introduced on the univer- 

 sit} T campus at Tucson, Ariz.; Cuba; 

 tropical Asia. 



Figure 849. — Eriochloa procera, X 10. (Griffiths 1516, 



Ariz.) 



5. Eriochloa gracilis (Fourn.) 

 Hitchc. (Fig. 850.) Annual; culms 

 erect or decumbent at base, 40 to 100 

 cm. tall; blades flat, glabrous, mostly 

 5 to 10 mm. wide; racemes several to 

 numerous, approximate, ascending to 

 slightly spreading, 2 to 4 cm. long, 

 the axis and rachis softly pubescent, 

 the pedicels short-pilose; spikelets 4 

 to 5 mm. long, rather sparsely ap- 

 pressed-pubescent, acuminate, or the 

 glume sometimes tapering into an 

 awn-point as much as 1 mm. long; 

 sterile lemma empty; fruit about 3 

 mm. long, apiculate. O — Open 

 ground, often a weed in fields, Okla- 

 homa and western Texas to southern 

 California, south through the high- 

 lands of Mexico. (This species has 

 been referred to E. acuminata (Presl) 

 Kunth, an unidentified species of 

 Mexico.) 



Eriochloa gracilis var. minor 

 (Vasey) Hitchc. Mostly smaller, with 

 more crowded, less acuminate spike- 

 lets, the pedicels with a few long hairs 

 at the summit; fertile lemma about 

 as long as the glume and sterile lemma 

 (excluding the short points), obtuse 

 or slightly apiculate. O — Open 

 ground, Texas, New Mexico, and 

 Arizona; Mexico. 



6. Eriochloa contracta Hitchc. 

 Prairie cupgrass. (Fig. 851.) An- 

 nual; culms erect or sometimes de- 

 cumbent at base, pubescent at least 

 about the nodes, 30 to 70 cm. tall; 



blades pubescent, usually not more 

 than 5 mm. wide; panicle usually less 

 than 15 cm. long, contracted, cylin- 

 dric, the racemes appressed, closely 

 overlapping, 1 to 2 cm. long, the axis 

 and rachises villous; spikelets 3.5 to 

 4 mm. long, excluding the awn-tip, 

 appressed-villous; glume awn-tipped; 

 sterile lemma slightly shorter, acumi- 

 nate, empty; fruit 2 to 2.5 mm. long, 

 with an awn nearly 1 mm. long. O 

 — Open ground, ditches, low fields, 

 and wet places, Nebraska to Col- 

 orado, Louisiana and Arizona; intro- 

 duced in Missouri and Virginia. Dif- 

 fering from E. gracilis in the pubes- 

 cent foliage, subcylindric panicle, and 

 the awned fruit. 



7. Eriochloa punctata (L.) Desv. 

 (Fig. 852.) Perennial; culms in tufts, 

 usually 50 to 100 cm. tall; blades flat, 

 mostly 5 to 10 mm. wide, glabrous; 

 racemes several, ascending, overlap- 

 ping, 3 to 5 cm. long, the axis, ra- 

 chises, and pedicels scabrous only; 

 spikelets 4 to 5 mm. long, lanceolate, 

 rather sparsely appressed-pilose ; 

 glume tapering to an awn-point about 

 1 mm. long; sterile lemma a little 

 shorter than the glume, empty; fruit 

 about half as long as the glume, with 

 an awn 1 mm. long or more. % — 

 Marshes, river banks, and moist 

 ground, southwestern Louisiana and 

 southern Texas; American Tropics. 



8. Eriochloa michauxii (Poir.) 

 Hitchc. (Fig. 853.) Perennial; culms 

 erect, rather stout, 60 to 120 cm. tall; 

 blades flat or, on the innovations, some- 

 times involute, elongate, 2 to 14 mm. 

 wide, usually less than 1 cm., glabrous; 

 racemes ascending or spreading, usu- 

 ally numerous, 3 to 5 or even to 15 

 cm. long, the axis 15 to 30 cm. long, 

 this and the rachises densely velvety- 

 pubescent; spikelets narrowly ovate, 

 4 to 5 mm. long, appressed-villous, 

 acute; sterile floret usually with a 

 well-developed palea and stamens; 

 fruit 3 to 4 mm. long, hirsutulous at 

 apex, apiculate or with an awn not 

 more than 0.3 mm. long. % (E. 

 mollis Kunth.) — Brackish or fresh 

 meadows and marshes and sandy 



