Eleocharis quinqueflora (F.X. Hartmann) Schwarz
Habitat: Damp calcareous shores, ledges and swamps. [Non-tidal rivershore (non-forested, seasonally wet)]
Range: Circumboreal, south to New England and west to Iowa.
Aids to Identification: This spikerush is a perennial species with stems clustered on a short rhizome. Stems are normally 10-30 cm high, and not flattened. The solitary, terminal spikelet is ovoid, 4-8 mm long, with 3-9 flowers. The 2 lowest scales are the largest, up to 5.5 mm long. The achene is gray-brown with a thickened, confluent projection (tubercle).
Ecological characteristics: In Maine, this species is known to occur on rocky river shores and riverside seeps.
Phenology: Fruits July - September.
Synonyms: Formerly known as Eleocharis pauciflora (Lightf.) Link, Eleocharis pauciflora (Lightf.) Link var. fernaldii Svens., Scirpus quinquefolius F.X. Harmann, or in older treatments, as Scirpus pauciflorus Lightf.
Known Distribution in Maine: This rare plant has been documented from a total of 11 town(s) in the following county(ies): Aroostook, Oxford, Piscataquis.
Dates of documented observations are: 1894, 1916, 1933, 1934, 1941 (2), 1984, 1985, 2000, 2001 (4)
Reason(s) for rarity: Suitable habitat naturally scarce.
Conservation considerations: Maintain hydrologic integrity of its rivershore habitat, including the natural disturbance.