Rhizomes normally remaining horizontal, sometimes hollow-centered, air canals absent. Culms 2-8 m tall, to 3 cm thick; internodes typically sulcate distal to the branches. Culm leaves deciduous; sheaths 9-15 cm; fimbriae 2.2-7 mm; blades 1.5-3.5 cm. Topknots of 6-8 leaves; blades 16-24 cm long, 2-3.2 cm wide, lanceolate to ovate-lanceolate. Primary branches to 25 cm, erect or nearly so, with 0-1 compressed basal internodes, lower elongated internodes flattened in cross section. Foliage leaves: abaxial ligules usually ciliate, sometimes glabrous; blades subcoriaceous, persistent, evergreen, 8-15 cm long, 0.8-1.3 cm wide, bases rounded, abaxial surfaces glabrous or pubescent, strongly cross veined, adaxial surfaces glabrous or almost so. Spikelets 4-7 cm, greenish or brownish, with 8-12 florets. Glumes unequal, glabrous or pubescent, lowest glumes obtuse to acuminate or absent; lemmas 1.2-2 cm, usually appressed-hirsute to canescent, sometimes pubescent only towards the base and margins. Caryopses oblong, beaked, without a style branch below the beaks. 2n = 48.
Arundinaria gigantea forms extensive colonies in low woods, moist ground, and along river banks. It was once widespread in the southeastern United States, but cultivation, burning, and overgrazing have destroyed many stands.
From Flora of Indiana (1940) by Charles C. Deam
This species is restricted to southern Indiana. I have found it only in the counties bordering the Ohio and Wabash Rivers. Kriebel, however, found it along Beaver Creek near Huron, Lawrence County, and there is a place named "cane marsh" in Greene County which indicates that it, at one time, did occur in that county. This species is usually found in lowlands that are periodially inundated. I have seen it on rocky wooded slopes, however, and on the top of the bluff of the Ohio River, where it was 200 feet above the water. In my opinion fire and grazing have been instrumental in limiting its distribution on the uplands.
Culms to 3+ m from a system of rhizomes, forming dense brakes; sheaths glabrous or hairy, ciliate, truncate at the summit and bearing a few long deciduous bristles on each angle; blades 10-30 cm, usually hairy beneath, sometimes also above; aerial stems monocarpic, sometimes some of them flowering the first year, but others only after several years, then forming fastigiately branched panicles on the old wood; first glume to 6 mm, or wanting; second glume to 12 mm; lemmas acuminate, the lower 15-20 mm; 2n=48. Damp woods, wet ground, and swamps; Md. and Va. to s. O. and s. Ill., s. to Fla. and Tex. (A. macrosperma; A. tecta)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.