Tasmania is home to many local native grass species, as well as 150 non-native grass species. Some of these non-native grasses present little-to-no significant threat while others can be serious problems in ornamental and home gardens, natural and semi-natural areas, urban and industrial landscapes, and agricultural and horticultural settings.
3D images for identification
We are developing online resources to help landowners and land managers to identify and control invasive perennial grasses.
The first stage in this process is presenting computer-generated, 3D images in Sketchfab to help identify eight of these grasses.
The 3D images were produced by Tasmanian botanical illustrator, Rachel Klyve. They show all details of the plant including leaves, flowers, seeds and roots, to help people identify plants in the wild.
Four invasive perennial grasses are presented on Biosecurity Tasmania's Sketchfab page. If the 3D images are not accessible for you please contact the Invasive Species Branch invasivespecies@nre.tas.gov.au
Another four invasive perennial grasses are presented below by the NSW Department of Primary Industries and Regional Development.
More resources will be added at this webpage over time so be sure to check back here for updates.
Invasive perennial grass species
Of the 150 non-native grasses found in Tasmania, invasive perennial grasses are the most problematic. Invasive perennial grasses threaten both rural production and natural and semi-natural areas and are recognised as among the most serious weeds in the state.
The species in this group are:
Economic impact
Invasive perennial grasses may have a major economic impact on farms and rural enterprises because they:
outcompete desirable pastures and crops
reduce stock carrying capacity
affect stock movement
taint meat, wool and fur
may cause injuries to livestock and farm animals.
Environmental impact
Invasive perennial grasses can have a major impact on local native grasslands, grassy woodlands and forests. They:
impact on the quality and diversity of the native ground-flora
affect shrub and overstorey regeneration
increase the risk and intensity of bush fires.
reduce the quality and extent of habitat available for local native fauna
Background
The invasive perennial grasses found in Tasmania originate from South America and southern Africa.
They were introduced to Australia:
accidentally, as impurities in agricultural produce
deliberately for pasture purposes or as ornamental garden plants
They do well here and in mainland Australia due to:
fast growth rates, mass seed production, ease of reproduction and long-lived seed (remaining dormant in the soil for many years)
highly effective dispersal mechanisms for seed and reproductive propagules (i.e., rhizomes - underground stems)
ability to exploit disturbed and modified environments
similarities between their home range and conditions here
lack of diseases and predators, unlike in their home ranges
Control Methods
Controlling invasive perennial grasses takes time and resources. It also requires integrating a range of control measures.
Depending on the situation, controls include:
A method that works in a highly modified, horticultural setting may not be appropriate in a natural area due to possible impacts on threatened native flora and fauna.
Remember to always select controls that suit your resources and circumstances.
More information
For more information on the control and management of individual invasive perennial grasses, refer to the specific species information on our Weeds Index webpages.