The CRC for Australian Weed Management has named buffel grass on a list of invasive species which pose an immediate threat to Australian flora and fauna.

The list also contains notorious weeds like cat's claw and Coolatai grass, a pest for NSW graziers.

But buffel grass is a preferred pasture throughout the northern cattle industry, and forms an integral part of Queensland grazing systems.

CRC for Australian Weed Management (Weeds CRC) scientist and president of the Council of Australasian Weed Societies, Dr John Virtue, says invasive weed species are expanding in cleared country and bushland remnants, threatening the survival of native plants and animals already stressed by severe habitat loss and changing rainfall and temperature patterns.

"Much of the current focus is on establishing biodiversity corridors to enable native plants and animals to migrate in the future, to more suitable climates," Dr Virtue said.

"Yet this won't happen if exotic weeds destroy the remnants of natural habitat we still have left.

"We need to actively manage weed threats now as a fundamental part of our response to climate change."

Launching a new series of weed management guides for Australian landholders and bushland managers by the Weeds CRC at the inaugural SA Weeds Conference in Adelaide today, Dr Virtue said the plight of Australia's native plants and animals under these pressures is poorly recognised.

"Research by the Weeds CRC shows that invasive foreign weeds now threaten the survival of almost half the 945 native plants and animals on the threatened species list for NSW alone," he said.

"We think this pattern of threat to native biodiversity by invasive weeds is likely to be widespread across Australia, especially for patches of remnant vegetation near cities, towns and farmhouses where ex-garden plants have jumped the fence."