Australia Slams the Door on Thousands of Weed Species

CANBERRA, Australia, June 8, 2005 (ENS) - Australians are being urged to help keep invasive plants out of the country, following tough new bans on plant imports by the federal government.

The government has banned importation of 3,335 potential weeds to protect the nation's agriculture and environment. Announcing the ban June 1, Conservation Minister Senator Ian Macdonald said the removal of these potential weeds marks the end of the first stage of a major project to remove whole groups from the list of permitted seed imports.

Blackberry, Rubus fruticosus aggregate, is Australia's worst weed. It invades the banks of watercourses, roadsides, pastures, orchards, plantation forests and bushland throughout temperate Australia making access difficult or impossible. (Photo courtesy CSIRO)

Following the consultations, Biosecurity Australia determined 3,335 species on the list are not present in Australia. The government will permit imports of these species only if a weed risk assessment determines their weed potential in Australia is low.

The eight worst weeds in Australia have already largely taken over more than 20 million hectares of countryside, despite strenuous efforts and huge expense to control them, and scientists are finding 20 new weeds established in the wild every year - plants that have escaped from people's gardens, ponds or aquariums.

"The second stage of the review will remove genus-level listings from the permitted seeds list. This means Australia will target individual plants rather than groups of plants," the senator said.

Biosecurity Australia is preparing information for consultations during the second stage of the review, expected to be complete next year.

Alligator weed, Alternanthera philoxeroides: Amaranthaceae, is an invasive plant that originates from South America and is currently invading Australia. (Photo courtesy CSIRO)

Dr. Rachel McFadyen, chief executive officer of the Australian Weed Management CRC, said, "Invasive plants are unquestionably the most devastating and costly environmental problem we face. They add over $4 billion to the price of our food and they are causing absolute havoc in our National Parks, river systems and native bush," she says.

"The first open door to new plant invaders has now closed," McFadyen said.

An example of plant threats excluded under the new ban are grasses related to the devastating pasture weed serrated tussock which is a potential threat to 30 million hectares of grazing land in southern Australia.

One of these, Mexican feather grass, was imported as an ornamental, started spreading in New South Wales and is now being eradicated. Importation of these weedy grasses is now banned.

Since European settlement, Australia has imported around 28,000 alien plants - more than the total number of native plant species - and one in 10 of these imports has established with adverse impact on farming or the environment.

"A lot of Australians still don't see invasive plants as much of a problem - probably because they are hard to recognize," McFadyen said. "But they are swallowing entire landscapes, including some of our most beautiful and iconic, and they are causing a spate of new health problems."

Mexican feather grass, Nassella tenuissima, looks pretty in a garden. It is not so pretty spread across hundreds of hectares. (Photo courtesy Victoria DPI)

The ban alone will not keep out new weeds, authorities recognize. Individual Australians are being asked to cooperate.

"We know a lot of seed and plant smuggling still goes on. People see something pretty while they are overseas on holiday and take it for their garden. People see attractive foreign plants on the Internet. People like to collect rare or unusual plants," McFadyen said.

"But every one of these apparently minor infringements contains the seeds of disaster for our landscape and our native species of plants, birds and animals."

"However the good news is that, by getting onto new outbreaks early, they can be wiped out and we are finding that even the major weeds can be checked using a range of scientific methods.

"But curing invasive plants still costs the taxpayer or landholder a fortune," McFadyen said. Prevention is far wiser and cheaper."

Find out more at: www.weeds.crc.org.au