Information about Spinifex or hummock Grasslands

Spinifex or hummock Grassland covers 22% of the Australian continent, and is the most extensive vegetation type in Australia. It covers sandhills, sand plains and rocky ranges from the Pilbara and the Kimberly in the north west to the Mallee in Victoria. Ernest Giles called it an abomination, as it was most uncomfortable to travel through, wounding his horses legs with its needle like spikes. It is a plant that is extremely well adapted to surviving in the arid zone. There are two genera -Plectrachne and Trodia, and they are both endemic to Australia. There are around 35 species, of Troidia and 11 of Plectrachne the most species occurring in the desert ranges. Trodia basedowii or lobed spinifex is the most drought resistant species and is seen throughout the Simpson Desert as well as in the Great Victoria and Great Sandy Deserts. Its has an unusual growth pattern where the inner grass dies off and new stems sprout from the outside forming concentric patterns. Triodia pungens occurs in the highest rainfall areas and requires better soil. Plectrachne schinzii takes the middle ground.

Spinifex is a fire plant, and there has been frequent burning throughout history, including the much publicised "fire-stick farming" practises of the Aboriginals. As the plant continues to accumulate biomass, its volatile resins are explosive. The thermoplastic black resin used by Aboriginals as a cementing agent is obtained from spinifex. In the Spinifex grasslands, reptiles, termites and ants dominate. The ants and termites feed on the Spinifex seed and the reptiles in turn feed on the ants. The food chain bears a curious similarity to the Serengeti Plain; the ants are the zebra and wildebeest, the reptiles the lions. Back to Land System introduction.

Bibliography
Further reading and information on sources for this website and the Outback.

Westprint Maps
For the best selection of Australian outback maps, click here to go to Westprint and order online today.