Juncus articulatus L.
Jointed Rush
Extremely variable, 6-60 cm high, dark green, commonly reddish-tinged, loosely or densely tufted or forming open colonies, rarely erect, more often decumbent or prostrate and rooting, or occasionally floating; rhizomes usually short with short internodes or occasionally long and giving rise to mat-like colonies. Leaves terete to ± compressed with transverse septa ± visible externally. Inflorescence very variable, 1-15- (40) cm long. Flowers in small dark brown clusters of 4-8 at tips of branchlets. Tepals 2.5-3 mm long, all ± equal, acute. Stamens 6. Capsule 2.5-3.5- (4) mm long, > tepals, ovate-oblong, trigonous, acute, upper third tapering to a distinct mucro, glossy, dark brown to black.
N., S., St., Ch., A., C. Occurring in swampy and wet places generally throughout; a significant weed in roadside channels and other drains, water races, streams and rivers. (Eurasia, N. Africa, N. America)
First record: Kirk 1875: 378, as "J. lamprocarpus Ehr."[J. lampocarpus Ehrh. ex Hoffman].
First collection: Christchurch, J. B. Armstrong, 1864(CHBG).
The most variable, widely occurring and abundant of the septate-leaved rushes; the acute, glossy, dark brown to black capsules > tepals distinguish it from allied spp. - J. acuminatus, J. canadensis, and J. microcephalus : for other differences, see these spp.
It sometimes forms a considerable element in poor pastures on wet soils and in swampy ground, but is often inconspicuous as the leaves are close-grazed, and flower heads are rarely allowed to develop. It appears relatively palatable in some localities, and is grazed even when other herbage is available.
