POACEAE 147 



Panicle open, usually less than 2.5 dm. long, its branches spreading or ascending : spike- 

 lets not crowded. 

 Spikelets 1.5 mm. wide or less : palets remaining attached to the continuous rachis for 

 some time after the flowering scales have fallen. 

 Flowering scales thin, usually bright purplish, the lateral 



nerves faint or wanting : spikelets about 1 mm. wide. 5. E. pilosa. 



Flowering scales firm, usually dull purple or green, the lateral 



nerves very prominent : spikelets about 1.5 mm. wide. 6. £. J'urshii. 



Spikelets more than 2 mm. wide : palets falling with the flowering 



scales and the internodes of the rachis. 7. E. major. 



** Perennials. 



Spikelets scattered on long branches. 



Branches of the open panicle spreading or ascending, rather stiff. 



Lateral nerves of the flowering scales faint. 8. E. Itigeni'. 



Lateral nerves of the flowering scale very prominent. 



Spikelets short-pedicelled, the pedicel 1 mm. long or less. 9. E. cuHipedicellata. 



Spikelets on pedicels which are often as long as or much ex- 

 ceeding the spikelet. 

 Pedicels usually less than twice as long as the spikelet. 

 Margins of the flowering scales convex above the middle, 



the scales hence merely acute. 10. E. pectinacea. 



Margins of the flowering scales straight or concave above 



the middle, the scales hence acuminate. 11. E. refracta. 



Pedicels many times longer than the spikelets. 12. E. Elliotiii. 



Branches of the narrow and elongated panicle long and flexuous, 



erect or nearly so. 13. E. trichodes. 



Spikelets crowded and clustered on short branches : 



Linear-lanceolate, 2 mm. wide or less. 14. E. simplex. 



Oblong to oval, exceeding 3 mm. in width. 



Flowering scales 3^ mm. long, acute. Arm. 15. E. secundiflora. 



Flowering scales 5 mm. long, acuminate, thin and papery. 16. E. Beyrichii. 



h. Palets of the spikelets beautifully and conspicuously ciliate with long 

 hairs. 

 Panicle contracted, spike-like, the branches short and appressed. 17. E. ciUarin. 



Panicle oY)en, its branches spreading. 18. E. plumosa. 



B. Stems creeping, rooting at the nodes. 



Flowering scales less than 2 mm. long, glabrous. 19. E. hypnoidcs. 



Flowering scales 3-4 mm. long, pubescent. 20. E. capitata. 



1 Eragrostls Frdnkii Steud. Stems 1.5-4 dm. tall, tufted, erect, often decumbent at 

 the base, branching : leaf-blade,s 5-13 cm. long, 2-4 mm. wide, rough above : panicle 5-15 

 cm. long, open, its branches ascending : spikelets ovate, 2-3 mm. long, 3-5-tiowered, the 

 flowering scales acute, the lower ones 1.5 mm. long, their lateral nerves obscure. 



In moist places, Connecticut to Minnesota, Mississippi, Louisiana and Kansas. Fall. 



2. Eragrostls capill^ria (L. ) Nees. Stems 2-5 dm. tall, slender, erect, finally 

 branching at the base : leaf-blades 7-25 cm. long, 2-4 mm. wide : panicle diil'use, 1-4 dm. 

 long, its capillary branches spreading or ascending : spikelets ovate, 2-3 mm. long, 2-4- 

 flowered, the flowering scales acute, 1.5 mm. long, their lateral nerves obscure. 



In dry places, Rhode Island and New York to Missouri, Georgia and Texas. Summer and fall. 



3. Eragrostls hlr.siata (Michx.) Nash. Stems densely tufted, rather stout, 7-13 dm. 

 tall : leaf -sheaths, at least the lower ones, strongly papillose-hispid, each with a tuft of hairs 

 at the apex ; blades, the lower leaves, 4-6 dm. long, less than 1 cm. wide, long-acuminate, 

 flat : panicle 5-8 dm. long, diffuse, its long brandies finally widely spreading : spikelets 

 3-5-flowered, 3-4 mm. long, the flowering scales 2-2.5 mm. long. 



In dry fields, thickets and woodlands, South Carolina to Florida, the Indian Territory and Texas. 

 Summer and fall. 



4. Eragrostls glomerata (Walt.) L. H. Dewey. Stems erect, rather stout, 2.5-8 



dm. tall : leaf-slieatlis glabrous ; blades rough, 2 dm. long or less, less than 1 cm. Avide, 



long-acuminate : panicle narrow, contracted, 1-5 dm. long, its branches erect or nearly so : 



spikelets 5-10-flowered, 2.5-3.5 mm. long, the flowering scales about 1 mm. long. [E. 



conferta Trin.] 



In damp or wet places. South Carolina to Florida, Louisiana, Arkansas and Texas. Also in Mexico. 

 Summer and fall. 



5. Eragrostls pilosa (L. ) Beauv. Stems tufted, 1.5-5 dm. tall, erect, slender, 



branched : leaf-blades 2-13 cm. long, 2 mm. wide or less : panicle 5-15 cm. long, its 



branches finally .spreading, often hairy in the axils : spikelets 5-1 2-flowered, 3-6 mm. long, 



about 1 mm. wide, the flowering scales acute, the lower ones 1.5 mm. long, thin, the lateral 



nerves faint or wanting. 



In cultivated ground or waste places, southern New England to Illinois, Kansas, Florida and 

 Texas. Naturalized from Europe. Summer and fall. 



6. Eragrostls Purshll Schrad. Steins 1.5-5 dm. tall, tufted, finally much-branched : 

 leaf-blades 3-11 cm. long, 2 mm. wide or less : panicle 7-20 cm. long, open, its branches 

 spreading, naked in the axils : spikelets 5-15-flowered, 3-8 mm. long, about 1.5 mm. wide, 

 the flowering scales acute, firm, the lower ones 1.5 mm. long, the lateral nerves prominent. 



In dry places, throughout the I'nited States and extending into Ontario. Summer and fall. 



