Description: This introduced perennial grass is 2½–3½' tall and usually unbranched. The culms are dull green, hairless or slightly pubescent, and terete. The blades of the alternate leaves are up to 10" and 2/3" across; they are greyish blue on the upper side, green on the lower side, hairless, and flat. The leaf blades are ascending to spreading and somewhat floppy in habit. The leaf sheaths are greyish blue, hairless, and closed, although they usually split open near the ligules.
Each culm terminates in a panicle of floral spikelets up to 8" long; the entire panicle has a tendency to lean sideways or droop from the weight of the spikelets. The branchlets of this panicle are ascending to spreading during the period of bloom, otherwise they are more erect and contracted. The branchlets occur in whorls along the central stalk of the inflorescence, and they often divide into secondary branchlets. These branchlets are green, hairless, and somewhat wiry. Each elongated spikelet is about ¾–1¼" in length; it consists of a pair of glumes and 5-10 fertile lemmas that are arranged in 2 columnar ranks. During the period of bloom, the spikelets are whitish green, sometimes with purplish or reddish tints. The glumes are about 1/5" (5 mm.) to 1/4" (6 mm.) in length; they are narrowly lanceolate, hairless, and shorter than the lemmas. The individual lemmas are about 1/3" (8 mm.) to 1/2" (12 mm.) in length; they are narrowly lanceolate, hairless, and usually awnless. On rare occasions, some plants may have lemmas with awns up to 2 mm. in length. The outer surface of each lemma has several longitudinal veins. The blooming period occurs during early to mid-summer. Shortly afterwards, the spikelets and culms become light tan. The elongated grains are about 1/3" long and light tan or brown. The root system is fibrous and produces abundant rhizomes. Dense colonies of plants are often formed.