Spikelets 1-flowered, and (in our species) often with a pedicel or rudiment of a second abortive flower (rarely 2-flowered), in an open or spiked panicle. Lower glumes mostly membranaceous, keeled or boat-shaped, often acute, commonly nearly equal, and exceeding the flower, which bears at the base copious white bristly hairs; flowering glume thin, bearing a slender awn on the back or below the tip, or sometimes awnless; the palet mostly shorter. Stamens 3. Grain free.—Perennials, with running rootstocks, and mostly tall and simple rigid culms. (Name compounded of κάλαμος, a reed, and ἀγρόστις, a grass.)
§ 1. DEYEÙXIA. Rudiment of a second flower present in the form of a plumose or hairy small pedicel behind the palet (very rarely more developed and having a glume or even stamens); glumes membranaceous, or the flowering one thin and delicate, the latter 3–5-nerved and awn-bearing.
[*] Panicle loose and open, even after flowering; the mostly purple-tinged or lead-colored strigose-scabrous glumes not closing in fruit; copious hairs of the rhachis about equalling the flowering glume, not surpassed by those of the rudiment; awn delicate, straight.
1. C. Canadénsis, Beauv. (Blue-Joint Grass.) (Pl. 8, fig. 1, 2.) Culm tall (3–5° high); leaves flat when fresh, glaucous; panicle oblong; glumes ovate-lanceolate, acute, 1¼–1½´´ long; awn from near the middle of the upper glume, not exceeding and scarcely stouter than the basal hairs. (Deyeuxia Canadensis, Hook. f.)—Wet grounds; common northward. July.
2. C. Langsdórffii, Trin. Spikelets larger, 2½–3´´ long; glumes lanceolate or oblong-lanceolate and gradually taper-pointed; awn stouter; otherwise like the preceding, (Deyeuxia Langsdorffii, Kunth.)—Mountains of N. New Eng., L. Superior, and northward. (Eu.)
[*][*] Panicle strict, its short branches appressed or erect after flowering, and the glumes mostly closed; flowering glume less delicate, roughish, sometimes of as firm texture as the lower; awn stouter.
[+] Leaves narrow, inclined to be involute; awn straight.
3. C. strícta, Trin. Panicle glomerate and lobed, strict, 2–4´ long; glumes 1½–2´´ long, ovate-oblong, not acuminate; hairs scarcely or little shorter than the flower, and as long as those of the rudiment; awn from the middle of the thin flowering glume or lower, and barely exceeding it. (Deyeuxia neglecta, Kunth?)—Mountains of N. New Eng., Lake Superior, and north and westward. (Eu.)
4. C. Lappónica, Trin. Culm and rootstocks stouter than in C. stricta; the narrow panicle less dense, and purplish spikelets larger; glumes fully 2´´ long, tapering to a point; awn from much below the middle of the glume, stout. (Deyeuxia Lapponica, Kunth.)—Isle Royale, Lake Superior, to Lab., north and westward. Aug. (Eu.)
[+][+] Leaves broader, flat; awn stouter, bent, divergent, or twisted when dry.