GRAMINEAE. 139 



5. Poa nemoralis L. Wood Meadow-grass. Northern Spear-grass. 

 (I. F. f. 470.) Culms 1.5-6 dm. tall, erect, slender, sometimes rigid. Leaves 2.5- 

 10 cm. long, 2 mm. wide or less, erect, smooth or rough; panicle 5-12.5 cm. in 

 length, open, the branches erect or ascending, rarely spreading, 2.5-5 cm - l° n g> 

 spikelets 2-5 -flowered, 3-5 mm. long; lower scales acute or acuminate, 1-3-nerved; 

 flowering scales obtuse or acute, 2-2.5 mm - l° n g> faintly 5-nerved, somewhat webby 

 at base, the midnerve and the marginal nerves silky-pubescent on the lower half. 

 Anticosti Isl. to Br. Col., south to Me., Minn., S. Dak., and in the Rocky Mts. to 

 Colo. Also in Europe and Asia. Summer. 



6. Poa flava L. False Red-top. Fowl Meadow-grass. (I. F. f. 471.) 

 Culms 4.6-15 dm. tall. Leaves 5— 15 cm. long, 2-4 mm. wide, smooth or rough ; 

 panicle 1.5-3 dm. in length, open, the branches spreading or ascending, 5-12.5 

 cm. long, divided and spikelet-bearing above the middle ; spikelets 3-5 -flowered, 

 3-4 mm. long, exceeding their pedicels ; lower scales acute, the flowering scales 

 obtibe, somewhat webby at the base, 2-3 mm. long, silky-pubescent on the lower 

 half of the marginal nerves and the midnerve, the intermediate nerves obscure or 

 wanting. In swampy places, N. S. and N. B. to Vancouver Isl., south to N. J., 

 111. and Neb. Also in Europe and Asia. July-Aug. 



7. Poa pratensis L. Kentucky Blue-grass. June-grass. (I. F. f. 466.) 

 Culms 3-12 dm. tall, from long running rootstocks ; leaves smooth or rough, 1-6 

 mm. wide, those of the culm 5-15 cm. in length, the basal much longer ; panicle 

 6-20 cm. in length, usually pyramidal, the branches spreading or ascending, some- 

 times flexuous, 2.5-7.5 cm. long, divided and spikelet-bearing above the middle; 

 spikelets 3-5 -flowered, 4-5 mm. long, exceeding their pedicels; scales acute; flower- 

 ing scales 3 mm. long, webbed at the base, 5-nerved, the marginal nerves and mid- 

 nerve silky-pubescent below, the intermediate ones naked. In meadows, fields, 

 and woods, almost throughout N. Am. Widely cultivated for hay and pasture. 

 Also in Europe and Asia. In N. Am. probably indigenous only in the northern 

 and mountainous regions. Variable. June-Aug. 



8. Poa glauca Vahl. Glaucous Spear-grass. (I. F. f. 469.) Culms 1.5-6 

 dm. tall, rigid, somewhat glaucous. Sheaths overlapping, confined to the lower 

 half of the culm ; leaves 2.5-5 cm - l° n g> 2 mm - wide or less, smooth beneath, sca- 

 brous above ; panicle 2.5-7.5 cm. in length, open, the branches erect or ascending, 

 I.25-3.75 cm. long; spikelets 2-4-flowered, 5-6 mm. long; empty basal scales acute, 

 3-nerved, glabrous, rough on the upper part of the keel; flowering scales 3-3.5 mm. 

 long, obtuse or acutish, rough, not webbed at the base, the lower half of the mid- 

 nerve and marginal nerves silky-pubescent, the intermediate nerves obscure and 

 occasionally sparingly pubescent at the base. White Mts. of N. H. Also in 

 Europe. Summer. 



9. Poa trivialis L. Roughish Meadow-grass. (I. F. f. 468.) Culms 3-9 

 dm. tall, usually more or less decumbent at the base. Sheaths rough; leaves 

 5-17.5 cm. in length, 2-4 mm. wide, generally very rough; panicle 1-1.5 dm. 

 long, open, the branches usually spreading or ascending, 2.5-5 cm - l° n g> spikelets 

 \i- or sometimes 3-flowered, 3 mm. long, exceeding their pedicels; scales acute; 



flowering scales 2-3 mm. long, webbed at the base, 5-nerved, the midnerve silky- 

 pubescent below, the lateral nerves naked, the intermediate ones prominent. In 

 Meadows and waste places, N. B. to Mich, and Va. Naturalized from Europe. 

 June-Aug. 



10. Poa debilis Torr. Weak Spear-grass. (I. F. f. 472.) Culms 3-7.5 

 dm. tall, slender, flattened. Sheaths compressed; leaves 2.5-11 cm. long, 2 mm. 

 wide or less, erect, smooth beneath, rough above; panicle 5-15 cm. in length, open, 

 often nodding at the top, the branches erect or ascending, sometimes spreading, 

 3-75-7-5 cm - l° n g"> spikelets 2-4-flowered, 3-4 mm. long, their pedicels longer; 

 flowering scales 3 mm. long, obtuse, sparingly webbed at the base, 5-nerved, the 

 nerves naked. In woods, N. S. and N. B. to Ont. and Minn., south to R. I., 

 Penn. and Wis. June-Aug. 



ir. Poa sylvestris A. Gray. Sylvan Spear-grass. (I. F. f. 474.) Culms 

 3-9 dm. tall, slender, slightly flattened. Leaves smooth beneath, rough above, 

 2-6 mm. wide, those of the culm 3.75-15 cm. in length, the basal much longer; 

 panicle 7.5-17.5 cm. in length, the branches spreading or ascending, sometimes 

 reflexed when old, 3.75-7.5 cm. long, spikelet-bearing at the extremities; spikelets 



