Common name: serrated tussock, Yass tussock, Yass River tussock, nassella tussock (NZ)
Nassella trichotoma (Nees) Hack. ex Arechav. APNI*
Description: Densely caespitose perennial to 0.7 m high, with numerous intravaginal innovations and wiry roots.
Leaves with ligule opaque-whitish, papery, obtuse or truncate, 0.5–2.5 mm long; blade convolute-filiform, bristly, 0.25–0.5 mm wide.
Panicle at length shortly exserted, pyramidal, effuse with rather few spikelets towards the tips of the ultimate branches, erect, 10–25 cm long, often purplish, the main axis somewhat compressed and planoconvex. Spikelets narrow-lanceolate, 5–7.5 mm long. Glumes narrow-lanceolate, lower as long as the spikelet, upper a bit shorter, 3-nerved. Lemma obovoid, obscurely 5-nerved, c. 2 mm long, with an eccentric awn to c. 3 cm long; callus bearded, pointed. Palea nerveless.
Distribution and occurrence: A very invasive weed that is widespread in southeastern Australia (far northeastern New South Wales south to Victoria and eastern Tasmania), covering more than 1.1 million ha. A weed of low-fertility hilly areas; also occurring on fertile flats; roadsides, pastures, scrub and woodlands. Native of S America, N.Z.
NSW subdivisions: *CC, *SC, *NT, *CT, *ST, *CWS, *SWS
Other Australian states: *Vic. *Tas.
A declared noxious weed for all areas of N.S.W.; it causes serious impacts on pastures and native habitats. See also Weeds in Australia profile compiled by P.G. Kodela (2007).
Text by S. W. L. Jacobs & J. Everett; revised by P.G. Kodela (July 2012)
Taxon concept: Flora of NSW 4 (1993)
APNI* Provides a link to the Australian Plant Name Index (hosted by the Australian National Botanic Gardens) for comprehensive bibliographic data
***The AVH map option provides a detailed interactive Australia wide distribution map drawn from collections held by all major Australian herbaria participating in the Australian Virtual Herbarium project.