silver tussockgrass (Poa labillardierei var. labillardierei)
This perennial tufted grass, with its dense foliage, silvery leaves and plume-like flower heads, is the most common Tasmanian tussockgrass, found in most saline soils in coastal areas. It is often found together with a relative grass, Poa poiformis.
Tasmanian Aborigines found its thin leaves ideal for fine weaving, making baskets, bags and mats from the tightly-woven fibres.
The plant’s greatest value is undoubtedly ecological. Like all coastal native grasses it is important as a binder of soil, growing where few other plants can take hold. The root systems of native grasses are much deeper than introduced grasses, making them more drought tolerant.
Other common native grasses in Taroona are:
- common wallabygrass (Rytidosperma caespitosum)
- kangaroo grass (Themeda triandra)
- coast speargrass (Austrostipa stipoides).
Only 0.5% of Tasmania's original grasslands survive, with most being cleared for pasture, cropping or housing.
Silver tussockgrass is a source of food for small seed-eating birds, and its roots and leaves are eaten by insects, notably butterfly larvae. In turn, the eastern barred bandicoot feeds on the insects, digging distinctive conical holes in grassy areas. Native birds scavenge the grassy forest understorey for seed-heads and insects. Many birds line their nests with dried grasses interwoven with spider webs. Silver tussockgrass is also a favoured habitat for reptiles such as the metallic skink and the blue-tongue lizard.
(Photos: Fiona Rice and Friends of Knocklofty)
STUDENT INQUIRY QUESTION
What do you think would happen if we didn't have any native grasses growing beneath trees and shrubs in the school's bushland and coastal areas?