Coolatai grass (Hyparrhenia hirta) is a perennial tussock-forming grass that invades pastures and native vegetation.
- perennial tussock grass to 2m tall
- main growing period and flowering is late spring and summer
- leaves are thin grey-green straps with a prominent midrib to 30cm long and 0.5cm wide
- flowers are grey-white spikes to 5cm, forming a ‘V” at the end of the stalks
- produces thousands of tiny sticky seeds to 2mm long, in hairy husk.
Why is it a problem?
- forms a dense monoculture and crowds out other ground cover
- fire hazard particularly on roadsides and in urban areas
- has low digestibility, and is not preferred by livestock
- preferential pasture species are consumed allowing coolatai grass to expand its area.
- Adelaide Hills
- Peninsula region
- Upper South East.
- infestations of coolatai grass can be found in areas where the average annual rainfall is between 400 - 800mm
- grows on many different soil types and under varied climatic conditions.
How it spreads
- produces thousands of tiny seeds with hairy awned husks which adhere to clothing, animals, machinery and vehicles
- seeds may also be transported via water along drainage lines.