Photo: Cyperus squarrosus

Cyperus squarrosus L.

Awned Flatsedge

  • State Rank: S2
  • Global Rank: G5
  • State Status: Special Concern
  • Habitat: Damp sands, silts, and alluvium [Non-tidal river shore (non-forested, seasonally wet)]

    Range: New Brunswick and Maine, south to Florida, west to Texas, north to British Columbia.

    Aids to Identification: Members of this genus can be difficult to identify without careful examination of microscopic features and an overall knowledge of the group. Cyperus species are identified by their 2-ranked scales of spikes, triangular stems, terminal inflorescences, and styles deciduous from the achene. Cyperus squarrosus is an annual with a cespitose habit. It is recognized by its 3 styles, 1 stamen, trigonous achene, and oblong-lanceolate, conspicuously ribbed, recurved floral scales.

    Photo: Cyperus squarrosus

    Ecological characteristics: Found along riverbanks and stream shores.

    Phenology: Fruiting in summer.

    Family: Cyperaceae

    Synonyms: Cyperus aristatus Rothbøll, Cyperus inflexus Muhl.

    Known Distribution in Maine: This rare plant has been documented from a total of 11 town in the following county: Hancock, Kennebec, Penobscot, Washington.

    Reason(s) for rarity: Population is approaching northern edge of range.

    Conservation considerations: Degradation to river shores could be detrimental to populations.