Elephants and maybe rhinoceroses could be introduced to Australia to chomp on an invasive African grass that also causes wildfires, according to an idea reported in a scientific journal on Wednesday.

"A major source of fuel for wildfires in the monsoon tropics is gamba grass, a giant African grass that has invaded north Australia's savannas," said David Bowman, a professor of environmental change biology at the University of Tasmania.

"It is too big for marsupial grazers (kangaroos) and for cattle and buffalo, the largest feral mammals. But gamba grass is a great meal for elephants or rhinoceroses."

Bowman, writing in the prestigious British journal Nature, admitted that introducing wild elephants to Australia "may seem absurd."

"But the only other methods likely to control gamba grass involve using chemicals or physically clearing the land, which would destroy the habitat," he said.

"Using mega-herbivores may ultimately be more practical and cost-effective, and it would help to conserve animals that are threatened by poaching in their native environments."

Bowman noted the destruction of other species that have been introduced to Australia and stressed that if the tusker were introduced Downunder, the move would have to proceed very cautiously.

Biologists would have to monitor the effect on the ecoystem and numbers would have to be controlled to prevent over-breeding.