FIELD ID CHARACTERISTICS:
Identification of Cyperus to species requires examination of fruits and mature achenes (containing a single seed). Mature achenes in this species are dark and distinctly three-angled.
Description: A small (usually about 15 cm but sometimes to 30 cm) weedy, grass-like clumping sedge with triangular flowering stems and flattened spikelets.
Leaves: Narrow, basal, linear leaves.
Flowers/Fruit: Narrow, flattened spikelets at the ends of flowering stems, usually in pairs or groups. Achenes, which are distinctly three-angled and black at maturity in this species, are in a folded scale, unlike Carex.
Habit and Range: Found statewide in sunny, disturbed damp areas like roadsides, driveways, fields, edges of impoundements.
COMMON CONFUSIONS:
Cyperus compressus (poorland flatsedge) is similar to C. flavescens (yellow flatsedge), which grows somewhat larger but has similar seedheads. In C. flavescens, mature achenes are not distinctly three-angled, but rounded and lens-shaped instead. Cyperus compressus is also similar to C. polystachyos (many-spike flatsedge) which only grows to 15 to 30 cm tall and mature achenes are flattened and elongated.
Click here to view Cyperus flavescens.
Click here to view Cyperus polystachyos.
Link to side-by-side comparisons page
