About Themeda quadrivalvis (L.) Kuntze
Themeda quadrivalvis (L.) Kuntze, commonly called grader grass, is an annual grass that reaches up to 2 meters (6 feet 7 inches) in height. Its typically folded leaves grow up to 60 centimeters (24 inches) long. Its seed heads are either rounded or fan-shaped, and are accompanied by leaflike bracts. The grass turns orange, red, or golden brown when it reaches maturity. The clustered spikelets held in the seed heads have tubercle-based hairs and twisted awns, which can grow up to 5 centimeters long. The awn is hygroscopic: it twists when moist, and drills the seed into the soil. This species is similar to the native species Themeda triandra, which is typically smaller and more brown in color. Grader grass produces seed prolifically, and a single seed head can hold up to 1000 seeds. Seeds are dispersed by road graders, on animal fur and human clothing, and as a contaminant of pasture seed supplies. Seeds may also sometimes be found as a contaminant of bird seed.
