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DescriptionThis native perennial grass is 2½5' tall and little branched. The erect central culm is green and terete (round in cross-section). The blades of the alternate leaves are up to 12" long and 2/3" across; they are greyish green to dark green, hairless, and rather floppy. The leaf sheaths are greyish green, finely ribbed, hairless, and sometimes glaucous. The ligule at the junction of the sheath and blade has a short papery membrane that eventually turns brown. The nodes are swollen and often whitened. The central culm terminates in a floral spike about 5-9" long; this spike is more or less erect. Pairs of spikelets occur sparingly along the spike; during the blooming period, they are perpendicular to the central stalk (or rachis) of the spike and widely spreading. Each spikelet has 2-4 florets. Usually, there are no glumes, although sometimes the lowest spikelets have glumes that are reduced to bristles up to 2/3" long. The lemmas are about ½" long and their straight awns are ½1½" long. Each lemma is lanceolate-linear, greyish green, and convex on the outer surface. The florets of the lemmas have 3 white anthers and a pair of plumose stigmas. In the typical variety of Bottlebrush Grass, the lemmas are hairless, however var. bigeloviana has pubescent lemmas. The blooming period occurs during the summer. Pollination is by wind. The spikelets easily detach from the central stalk of the inflorescence and fall to the ground; they become straw-colored with maturity. The seeds are long and narrow. The root system is fibrous. This grass spreads primarily by reseeding itself; it often forms small colonies of several plants.