Culms 28-185 cm, somewhat bulbous at the base; nodes 5-13. Ligules 2-10 mm; blades to 34.5 cm long, 3-19 mm wide. Panicles 6.5-55 cm; branches ascending to spreading. Spikelets (3.5)4-6(7.5) mm; rachilla prolongations 0.1-0.4 mm, sometimes absent. Lower glumes (2.7)3.5-5(6.1) mm, somewhat shorter than the lemmas, 1-veined; upper glumes (3.5)4-6(7.5) mm, equal to or slightly longer than the lemmas, 3-veined, awns 0.2-1.5 mm, or rarely absent; stipes 0.25-0.7 mm; lemmas (2.7)3.5-5(6.4) mm, 3(5)-veined, awns 0.2-1.5 mm or rarely absent; paleas 1-veined; anthers 1, 0.8-1.9 mm. Caryopses 2.1-2.8 mm. 2n = 28.
Cinna arundinacea grows in southeastern Canada and throughout most
of the eastern United States, at 0-850 m. It is most common in moist woodlands
and swamps, depressions, along streams, and in floodplain and upland woods,
and is less frequent in wet meadows, marshes, and disturbed sites. It flowers
in late summer to fall. Cinna arundinacea is most easily distinguished
from C. latifolia by its 3-veined
upper glumes and larger spikelets.
From Flora of Indiana (1940) by Charles C. Deam
Frequent to rather common in all parts of the state. It grows in wet soils in almost all kinds of habitats except in pure sand. This is a woodland species but is sometimes found in wet clearings if shaded by rank vegetation.
Culms erect, 10-15 dm, with usually 5-10 nodes; lvs 6-12 mm wide, scabrous at least on the margins; ligules tinged with reddish-brown; infl narrow, 1.5-3 dm, often somewhat drooping, with crowded, ascending branches, dull grayish-green; first glume 1-veined, 3.5-5.6 (avg 4) mm; second glume sharply 3-veined, usually distinctly scabrous, 4.1-6.6 (avg 5) mm, herbaceous nearly or quite to the margin; awn usually under 0.5 mm; anthers 0.8-1.8 mm; 2n=28. Moist woods; Me. to Ont., Minn., and N.D., s. to Ga. and Tex.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.