A Review of Kangaroo Grass (Themeda triandra Forssk.) Establishment Methods in Temperate Australia

Abstract

Kangaroo grass (Themeda triandra Forssk.) is a widespread summer-active native tussock grass that has been removed from many ecosystems through overgrazing, absence of fire or changes in land use. This review of kangaroo grass establishment trials in temperate Australia shows that it can be established from seed, but success varies depending on season, preparation of the area to be sown, sowing rates and methods, and especially on controlling competition from other plants until the kangaroo grass is large enough to suppress them. Controlling exotic plants before sowing kangaroo grass using physical, ecological or chemical methods has been effective but is often not enough to allow the kangaroo grass to establish well. Exotic plants emerging from the soil seed or bud bank after kangaroo grass emerges, have led to project failures or prevented kangaroo grass from thriving. Research will help us learn how to control exotic competitors, especially which methods to use and when. Furthermore, most methods of establishing kangaroo grass have been suited to small areas of up to several hectares, and broadacre methods need research and development. Given that seed is typically expensive or in short supply, efficient use of seed is essential; better ways to label, clean and sow the seeds of kangaroo grass are needed. The provenance of kangaroo grass seed is also important when used for ecological restoration as, broadly, plants with two chromosome sets (i.e., diploid) are better adapted to cooler/wetter regions and plants with four chromosome sets (i.e., tetraploid) are more suited to hotter/drier areas.