Eleocharis parvula is a perennial spikerush from small rhizomes, very small, hair-like, 2-6 cm tall, forming dense mats.
Leaves alternate, bladeless sheaths only.
Flowers dry, papery, no petals or sepals, stamens; spike solitary at top of stem, 0.3-0.6 cm long, oval, 2-9 flowers , scales green to brown about 0.2 cm, style 3-parted.
Fruit dry, 1-seeded (achene) straw-color, 3-sided, tubercle at top confluent with body, short.
Wetland status: OBL.
Frequency in NYC: Very infrequent.
Habitat: High salt marshes. Tolerant of fire, moderately tolerant of salt, intolerant of shade. Soil pH 6-8 (USDA, NRCS 2010).