Long-rhizomatous perennial. Culms erect, to 85 cm high, each with up to c. 5 leaves and 1–4 cataphylls towards the base, and 1–2 leaves above, fibrous remains of old cataphylls ± persisting. Leaf-blades solid, shorter or longer than culms, 0.5–2 mm wide, usually channelled toward base, flattening toward apex, underside with raised nerves, apex acute or eroding and appearing toothed; auricles obtuse, to c. 1 mm long. Inflorescence with flowers spaced along the ascending or diverging branches; primary bract leaf-like, ± exceeding the inflorescence; prophylls present. Tepals with a broad green midrib when young, margins reddish-brown, membranous, strongly incurved towards the tip; outer tepals 2.5–4 mm long, obtuse and hooded at tip; inner shorter than or equal to the outer, obtuse; stamens 6, anthers 1–2.2 mm long. Capsules light brown at maturity, ovoid, c. 3 mm long, shorter than to slightly exceeding the tepals, obtuse, with a fragile mucro; seeds c. 0.4–0.7 mm long, slightly asymmetric, with fine longitudinal and transverse ridges discernible at fairly low magnification, minutely apiculate at one or both ends. Flowers recorded Nov., fruiting period unknown.
GleP, DunT, HSF. Also naturalised Tas. Native to Europe, Asia, northern Africa, North America. In Victoria known from a single population discovered in 1950 on saline flats at Fawthrop Lagoon, Portland.
Several subspecies are recognised overseas but apparently only the subsp. gerardii occurs in Australia. Closely resembles J. revolutus and occupies a similar ecological niche, but differs in having taller culms, smaller tepals and capsules, and in consistently having 1–2 culm leaves.
