Scientific Name: Cyperus compressus

Common Name: poorland flatsedge

Habit: Annual sedge is a weed of container ornamentals, nurseries, landscapes, and turf. It typically occurs in areas of frequent irrigation or low-lying poorly-drained sites.

Leaves: Leaves of annual sedge are light green, shiny, linear in outline but tapering to a point, and three-ranked. Individual leaves may be from 3 to 8 mm wide. Plants range from 4 to 18 inches tall and leaves are shorter or equal in length to the flowering stems. Leaves arise from the plant base. When crushed, leaves emit a sweet fragrance. No ligules or auricles occur, as would be the case with most grass seedlings.

Identifying Characteristics: Annual sedge is one of several types of sedge that are found in turf. Annual sedge differs from many of the perennial sedges in that it lacks rhizomes and tupers in the fibrous root system. Annual sedge is also much shorter than purple or yellow nutsedge and the leaf blades are narrower.

Flower Seed Head: Terminal seedheads occur at the ends of the triangular stems of annual sedge. Seedheads are typically less than 10 inches but may reach 18 inches.Three to ten short spikelets are found in a dense cluster at the tip of each stem.

Seed Fruit: Seeds of annual sedge are dull brown three-angled achenes.

Where Found: Annual sedge is found in most of the US and often infests irrigated lawns or low-lying wet areas.

  • Life cycle: summer annual

  • Plant type: Sedge

  • Auricle: not present

  • Plant family: Cyperaceae

  • Leaf arrangement: rolled in bud

  • Hair surface: no hairs

  • Ligule: none

  • Length: none

  • Seed head: multiple spikes

  • Width: less than 5 mm; 6 to 15 mm

  • Grass stem: triangle