Juncus bufonius is an annual rush to 30 cm tall, tufted, often branched.
Leaves alternate, from base and stem, thread-like, 0.5-10 cm long to 0.1 cm wide, lower surface rounded, upper surface flat or channeled.
Flowers in clusters of 2-4, scattered along stems, above tiny membranous bracts 0.1-0.2 cm long, petals linear, 0.3-0.6 cm midrib green, margins membranous, slightly shorter than sepals; inflorescence a third or more of plant height.
Fruit capsule about as long as sepals, June-Nov.
Wetland status: FACW.
Frequency in NYC: Infrequent.
Habitat: Wet to moist soil, open sites, soil pH 4.6-7.6, moderately tolerant of salt, intolerant of shade, fire, drought (USDA, NRCS 2010).
Notes: Sometimes planted in wetland restorations.