This native perennial grass is 6-16' tall and unbranched; individual plants are erect or they may lean over with age. The culm is light green, hairless, and rather stout; it has small rectangular impressions across its surface. The alternate leaves are abundant along the culm and they are ascending. The leaf blades are up to 2' long and 2" across; they are light green or greyish blue, linear-lanceolate, and hairless. The upper surface of each leaf blade has conspicuous parallel veins. The leaf sheaths are the same color as the blades and they are hairless. The culm terminates in a panicle of spikelets up to 1½' long and half as much across. This panicle is densely branched and its branchlets are ascending or drooping. While the florets are in bloom, the panicle has a silky reddish appearance, although it becomes light tan later in the year. Each spikelet is up to 2/3" long and it has 3-7 florets; the lowest floret is sterile or staminate, while the remaining florets are perfect. At the bottom of this spikelet, there is a pair of linear-lanceolate glumes about ¼" long. The lemmas above the glumes are linear in shape and up to ½" long, becoming smaller as they ascend the rachilla (central stalk of the floret). Along the rachilla, there are tufts of long silky hairs. The blooming period occurs during mid- to late summer. The florets are wind-pollinated. Upon maturity, each perfect floret develops a grain, but it is often abortive or sterile. The root system consists of stout rhizomes and coarse fibrous roots. This grass often forms vegetative colonies that are sometimes quite large in size.