Aleman grass

On 1 July 2017, the Noxious Weeds Act 1993 was replaced by the Biosecurity Act 2015. The Weed biosecurity section of this website is being reviewed, and information currently on this page may not reflect the new legislation.


Flower heads are
15-30cm long.
Leaves are flat and
smooth, with rough
Aleman grass grows to 1-3m high. Aleman grass forms
dense stands.
Seed production is poor.

Aleman grass (Echinochloa polystachya) is an aquatic or semi-aquatic perennial grass growing to between one metre and three metres high. It forms dense stands in swampy areas and along banks of watercourses and is able to grow in water up to two metres deep.

Aleman grass originates from tropical and subtropical America. It was introduced to Queensland as a ponded pasture species and now invades seasonally flooded areas, swamps, and banks of watercourses. Infestations have also occurred in the Northern Territory, Western Australia and northern NSW.

There are eight infestations of Aleman grass known on the NSW North Coast.


  • Lower parts of stems are coarse and thick, arising from long, rooted runners. Leaves are flat and smooth, tapered, 20-50 cm long and 2-3.5cm wide, with rough edges.
  • Flower heads are 15-30cm long. Seed production is poor and most spread is vegetative, occurring when stems, runners and roots are moved in water.
  • Aleman grass is a class 2 noxious weed on the NSW North Coast under the Noxious Weeds Act 1993.
  • It must be eradicated and land must be kept free of the plant. As a notifiable weed, all outbreaks must be reported to the local control authority within three days and the plant is prohibited from sale in NSW.

Distribution map as at May 2017

Predictive mapping supplied by Queensland Biosecurity