9. Aristida Oligantha Michx. Few-Flowered Aristida

Fig. 431

Aristida oligantha Michx. Fl. Bor. Am. 1: 41. 1803.

Glabrous, culms 1°-2° tall, erect, slender, dichot-omously branched, smooth or roughish. Sheaths exceeding the internodes, loose; ligule very short, minutely ciliate; blades 1'-6' long, 1/2"-1" wide, smooth, the larger ones attenuate into a long slender point; spikelets few, borne in a lax spike-like raceme or panicle; first scale 5-nerved, occasionally 7-nerved at base, acuminate or short-awned, equalling or somewhat shorter than the second, which bears an awn 2."-4" long; third scale shorter than the first, awns divergent or spreading, the middle one 1Y-2Y long, the lateral somewhat shorter.

Dry soil, New Jersey to Nebraska, and Texas. Aug.-Sept. Ant-rice.

9 Aristida Oligantha Michx Few Flowered Aristida 431

10. Aristida Gracilis Ell. Slender Triple-Awned Grass

Fig. 432

Aristida gracilis Ell. Bot. S. C. & Ga. 1: 142. 1817.

Aristida gracilis var. depauperata A. Gray, Man. Ed. 5, 618. 1867.

Glabrous and smooth throughout, culms 6'-2° tall, erect, simple or branched. Sheaths shorter than the internodes; ligule very short; blades 1'-4' long, 1" wide or less, flat, or involute when, dry; panicle spike-like, 3'-7' long, slender; spikelets about 3" long; outer scales equal, or the lower somewhat shorter, awn-pointed; third scale about equalling the second, generally mottled, middle awn horizontal, the terminal straight portion 3"-7" in length, the lateral awns 1"-3" long, erect.

Dry soil. New Hampshire to Missouri, south to Florida and Texas. Aug.-Sept.

10 Aristida Gracilis Ell Slender Triple Awned Gras 43210 Aristida Gracilis Ell Slender Triple Awned Gras 433

11. Aristida Intermedia Scribn. & Ball. Plains Aristida

Fig. 433

A. intermedia Scribn. & Ball, Bull. U. S. Dep. Agr. Agrost. 24: 44. 1901.

Culms slender, finally branching, 1°-2 1/2° tall; sheaths glabrous or sparsely hirsute; blades 2'-6' long, 1" wide or less, erect, involute; panicle 8'-16' long, slender, its branches appressed; spikelets 4"-5" long, the empty scales manifestly awned, about equal, the flowering scale strongly hispidulous above the middle, equalling or exceeding the empty scales, the awns spreading, the middle one 7"-13" long, the lateral ones shorter.

In sandy soil, Iowa and Kansas to Mississippi and Texas. Aug.-Oct.

12. Aristida Purpurascens Poir. Arrow-Grass. Broom-Sedge

Fig. 434

Aristida purpurascens Poir. in Lam. Encycl. Suppl. i: 452. 1810.

Glabrous and smooth, culms 1°-2 1/2° tall, erect, simple or sparingly branched at the base. Sheaths longer than the internodes, crowded at the base of the culm; ligule very short; blades 4's' long, about 1" wide, flat, or becoming involute in drying, attenuate into a long point; spike-like panicles 5'-18' long, strict, or sometimes nodding, its branches appressed; outer scales of spikelet awn-pointed, the first longer than the second; the third scale from two-thirds to three-quarters as long as the first, middle awn 9"-12" long, horizontal, the lateral awns somewhat shorter, erect or divergent.

In dry soil, Massachusetts to Minnesota, south to Florida and Texas. Sept.-Oct.

12 Aristida Purpurascens Poir Arrow Grass Broom Se 434