Nassella trichotoma
(Nees) Hack Serrated TussockTufted perennial, culms shorter than or shortly exceeding leaves, to 50 cm high, nodes pubescent but usually concealed by leaf-sheaths. Leaves scabrous; blade involute, filiform, to c. 30(–50) cm long and 0.5 mm diam.; ligule membranous, glabrous, truncate, continuous with margins of sheath, 0.5–1 mm long. Inflorescence a slender panicle with ascending branches, fully exserted from upper leaf sheaths, expanding fully and falling entire at maturity. Glumes 6–10 mm long, strongly purplish in lower part, long-acuminate, subequal; lemma cylindric to obovoid, truncate at apex, 1.5–3 mm long, pale brown to purplish at maturity, strongly antrorsely scabrous in the upper part; corona absent or a few uneven bristles to 0.5 mm long sometimes surrounding awn-base; callus c. 0.3 mm long with white hairs to 1.2 mm long; awn straight or obscurely twice bent, 25–35 mm long, twisting in the lower one-third, scabrous; palea hyaline, 0.3–0.6 mm long. Flowers Sep.–Dec.
Wim, VVP, VRiv, GipP, OtP, Gold, CVU, DunT, NIS, EGL, EGU, HSF, HNF, OtR. Also naturalised in NSW, ACT, Tas. Indigenous to South America (Argentina, Bolivia, Chile, Paraguay) in pampas country. First noticed in Victoria in 1954, now well-established in poorly maintained pasture, particularly immediately north and west of Melbourne, but also near e.g. Hamilton, Bendigo, Bairnsdale areas.
Nassella trichotoma has the ability to rapidly become established to the exclusion of other native or pasture species, particularly on dry, infertile soils. It has no value as a fodder species and is a declared noxious weed. Spread is likely via agricultural machinery and movement of stock. It is regarded as 'A Weed of National Significance'.
Walsh, N.G. (1994). Poaceae. In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 2, Ferns and Allied Plants, Conifers and Monocotyledons, pp. 356–627. Inkata Press, Melbourne.
Spinning
