, is one of 129 US species in this genus, part of the pycnostachys subgroup which is characterized by florets with three (rather than two) stigmas, three-angled seeds, and spikelets (the inflorescence) arranged in hand-shaped clusters rather than elongated clusters. The green stems are triangular in cross-section, hairless, several feet tall, and produce a whorl of long, strap-like leaves at the tip, bending back downwards. Leaves have prominent lengthwise veins.
The inflorescence forms in spring at the base of the upper leaves; it consists of 3 to 10 rays, bearing between 30 and 50 spikelets, each of which carries between 20 and 30 florets. The inflorescence is colored greenish yellow, often brown towards the center of the spikelets.