Plants perennial; rhizomatous, rhizomes short, usually more than 1 cm thick. Culms 2-10 m tall, 1-3.5 cm thick, usually erect, occasionally pendant from cliffs; nodes glabrous; internodes hollow. Leaves cauline, conspicuously distichous, glabrous; sheaths open, longer than the internodes; ligules membranous, shortly ciliate; blades flat or folded, margins scabrous. Panicles terminal, plumose, silvery to purplish. Spikelets laterally compressed, with 1-several florets; rachilla segments glabrous; disarticulation above the glumes and between the florets. Glumes longer than the florets, 3-5-veined; lemmas pilose, hairs not papillose-based, 3-7-veined, apices entire or minutely awned; paleas shorter than the lemmas, 2-veined; anthers 3. x = 12.
Del., W.Va., Pacific Islands (Hawaii), Fla., Tex., La., Tenn., N.C., S.C., Nev., Va., Calif., Puerto Rico, Virgin Islands, Ala., Ark., Ill., Ga., Ariz., N.Mex., Md., Okla., Utah, Mo., Kans., Miss., Ky.
Arundo, a genus of three species, grows throughout the tropical and warm-temperate regions of the world. Only one species has been introduced to the Western Hemisphere.
Arundo is similar to, but usually larger than, Phragmites, a much more common genus in North America. In addition, Arundo, but not Phragmites, has a wedge-shaped, light to dark brown area at the base of its blades.