Astrebla is a small genus of xerophytic (adapted to survive in an environment with little liquid water) grasses found only in Australia.[2] They are the dominant grass across much of the continent.[3] They are commonly known as Mitchell grass after Scottish explorer Thomas Mitchell (1792-1855), who first collected a specimen near Bourke in New South Wales.
| Mitchell grass | |
|---|---|
 | |
| Astrebla pectinata | |
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Monocots |
| Clade: | Commelinids |
| Order: | Poales |
| Family: | Poaceae |
| Subfamily: | Chloridoideae |
| Tribe: | Cynodonteae |
| Subtribe: | Eleusininae |
| Genus: | Astrebla F.Muell.[1] |
| Type species | |
| Astrebla pectinata | |
Mitchell grasses grow on clay soils, mainly between an upper limit of 600 millimetres or 24 inches and a lower limit of 200 millimetres or 8 inches average annual rainfall, and at even lower rainfall in depressions where the water concentrates following rains, for example in Sturt's Stony Desert. Mitchell grasses are deep-rooted and become dormant during drought, allowing them to survive extended periods without rainfall.[4][5]
They are commonly found clumped together and reaching one metre high, providing habitat for organisms such as mammals.[6]
| Scientific name | Common name | Characteristics |
|---|---|---|
| Astrebla elymoides | hoop Mitchell grass | the second most common species |
| Astrebla lappacea | curly Mitchell grass | the most common species |
| Astrebla pectinata | barley Mitchell grass | the most drought-tolerant species |
| Astrebla squarrosa | bull Mitchell grass | the most flood-tolerant species |