Mexican feather grass (Nassella tenuissa)
Close look at Mexican feather grass
Mexican feather grass is declared a Class A (to be eradicated) and Class C (not to be introduced to the Northern Territory) weed in accordance with the NT Weeds Management Act 2001.
- Mexican feather grass Photo Identification Table (pdf 112Kb)
Mexican feather grass (Nassella tenuissa), a native from southern USA, Chile and Argentina, poses a potentially serious new weed threat to Australia. The species is closely related to other exotic grasses, including serrated tussock (N. trichotoma) and Chilean needle grass (N. neesiana), both of which are Weeds of National Significance (WoNS). Serrated tussock is widely regarded as the worst pasture weed in Australia and is estimated to cost Australia more than $50 million a year in lost productivity and weed control costs. Mexican feather grass is similar to serrated tussock in terms of ecology and growth and has the potential to invade up to 14 million hectares in Australia, a far greater area than serrated tussock. Each Mexican feather grass plant can produce between 70 000 and 100 000 seeds per year.
Mexican feather grass is not known to be present in the Northern Territory. Its declaration prohibits its entry into and movement within the NT and provides a consistent and coordinated management approach to and from other States and Territories.
Mexican feather grass was introduced to Australia when mislabelled and sold as an ornamental plant under the names Elegant Spear Grass, Pony Tail and Angel's Hair. In 2008 an estimated 4000 Mexican feather grass plants were supplied and sold through retail stores in Victoria, Queensland and New South Wales. Following prompt action by DPI officers and retailers in Victoria, suspect plants were removed from sale and a state-wide recall of Mexican feather grass plants was initiated.
Mexican feather grass has escaped from cultivation in New Zealand and has become a weed that is continuing to spread. It is not known to be naturalised anywhere in Australia at the present time however Mexican feather grass has now been found in Victoria, New South Wales, Queensland and Western Australia.
Landholders are urged not to attempt to control or dispose of Mexican feather grass themselves. If you suspect that you may have, or have seen, Mexican feather grass, contact the Weed Management Branch on (08) 899 94567 for advice on identification and safe removal.
