Cyperus esculentus (also called chufa sedge, nut grass, yellow nutsedge, tiger nut sedge, or earth almond) is a crop of the sedge family widespread across much of the world. It is native to most of the Western Hemisphere as well as southern Europe, Africa, Madagascar, the Middle East and the India Subcontinent. It has become naturalized in many other regions, including Ukraine, China, Hawaii, Indochina, New Guinea, Java, New South Wales and various oceanic islands.
C. esculentus is an annual or perennial plant, growing to 90 cm (3 feet) tall, with solitary stems growing from a tuber. The plant is reproduced by seeds, creeping rhizomes, and tubers. The stems are triangular in section and bear slender leaves 3–10 mm (1/8 to 1/2 inches) wide. The spikelets of the plant are distinctive, with a cluster of flat, oval seeds surrounded by four hanging, leaf-like bracts positioned 90 degrees from each other. They are 5 to 30 mm (about 3/8 to 1 1/8 inches) long and linear to narrowly elliptic with pointed tips and 8 to 35 florets. The color varies from straw-colored to gold-brown. They can produce up to 2420 seeds per plant. The plant foliage is very tough and fibrous and is often mistaken for a grass. The roots are an extensive and complex system of fine, fibrous roots and scaly rhizomes with small, hard, spherical tubers and basal bulbs attached. The tubers are 0.3 – 1.9 cm (1/8 to 1/2 inches) in diameter and the colors vary between yellow, brown, and black. One plant can produce several hundred to several thousand tubers during a single growing season. With cool temperatures, the foliage, roots, rhizomes, and basal bulbs die, but the tubers survive and resprout the following spring when soil temperatures remain above 6 °C (42.8 °F). They can resprout up to several years later. When the tubers germinate, many rhizomes are initiated and end in a basal bulb near the soil surface. These basal bulbs initiate the stems and leaves above ground, and fibrous roots underground. C. esculentus is wind pollinated and requires cross pollination as it is self–incompatible.