Cyperus trachysanthos, a member of the Cyperaceae (sedge) family, is a short-lived perennial sedge with a short rhizome (underground stem). The culms (aerial stems) are densely tufted, obtusely triangular in cross section, 20 to 45 cm (8 to 18 in) tall, sticky, and leafy at the base. The linear leaf blades are green, covered with a waxy coating, and somewhat leathery. The leaf sheath is yellowish brown and partitioned with nodes. The flower clusters are 5 to 9 cm (2 to 3.5 in) long and 6 to 12 cm (2 to 5 in) wide. The flower head contains 10 to 30 pale, yellowish brown spikelets each of which contains 8 to 20 flowers. The glumes (small pair of bracts at the base of each spikelet) are broadly egg-shaped. The fruit is a dark-brown, egg-shaped achene.