Carex comans Berggr.
Very leafy dense red or yellow-green tufts to 25 cm high. Leaves concavo-convex, usually > stems, drooping above; sheaths dull brown to purple-black. Female spikes c. 5, distant, ± pedunculate, light brown to red-brown, to 2.5 cm × 3-4 mm. Utricle-beak deeply cleft, scabrid, ± 1 mm long. Stigmas 3.
N. Throughout. S. Very common; not known from Fiordland. St. In pasture, tussock grassland and damp river flats; lowland to subalpine.
Recognised by its dense tufts, narrow concavo-convex leaves, slender spikes and sharply toothed utricle-beaks. C. comans is sometimes mistaken at a distance, especially in drier sites, because of the colour and habit of its windswept tussocks, for the grass, Nassella trichotoma nassella tussock, a major weed of grassland in both islands.
C. comans is agriculturally the most significant of the indigenous spp. of Carex, being an increasingly troublesome weed of grassland over large areas in both islands, from the Volcanic Plateau and Taranaki to Southland where it has long been a problem and is known there as Longwood tussock. It is prominent on flats, or rolling and unploughable hill country, tolerating high or low rainfall, and wet to dry soils.
It invades newly sown grassland, lucerne crops occasionally, land brought in from modified tussock grassland or originally under indigenous forest. The tightly packed, green or reddish tussocks, vary in abundance from scattered plants, to dense dominant communities replacing the grassland so that control, or breaking up and re-sowing is necessary.
The recent increasing use of C. comans as an horticultural subject in pebble gardens has had an interesting effect on local distribution. It is now appearing as a persistent weed in cracks in footpaths and concrete gutter channels in towns, from seed carried by drainage water from domestic gardens and commercial garden centers.