From Enviroweeds list:

Department of Agriculture and Food
Government of Western Australia

Media Statement

3 Baron-Hay Court, South Perth, Western Australia 6151
Tel: (08) 9368 3333 Fax: (08) 9474 2018
www.agric.wa.gov.au


15 April
2008

INVASIVE WEED GIANT FOUND IN KIMBERLEY

One of the worst environmental weeds in Australia, not seen before in
Western Australia, has been stopped in its tracks and controlled in
the Kimberley by Department of Agriculture and Food Biosecurity officers.

Parthenium (Parthenium hysterophorus) can grow up to two metres high
and produce up to 100,000 seeds per plant. It costs Queensland more
than $22 million a year in reduced production and increased management
costs.

The Kimberley manager for the Department of Agriculture and Food Noel
Wilson said parthenium plants had been discovered growing by a
quarantine washdown bay in Kununurra during routine surveillance
carried out in this area.

"Our washdown bays are there to minimise the chance of weed seeds
entering Western Australia that could threaten our agricultural and
pastoral industries," Mr Wilson said.

"The seeds of this weed have been captured in a washdown of a vehicle
coming across the border, and they germinated within our quarantine
facility," Mr Wilson said.

"It is a real win for DAFWA's biosecurity efforts, and it indicates
the important role washdown facilities play in protecting Western
Australia's agricultural and pastoral industries," he said.

Parthenium weed affects the viability of primary production including
live stock and grain enterprises. It can also cause health problems
for humans and animals.

"It is toxic to stock, and people can have allergic reactions to its
pollen, causing dermatitis, hay fever and asthma," Mr Wilson said.

"It is a particularly bad environmental weed and its seeds adapt very
well to semi-arid environments such as the Kimberley environment. The
seeds can germinate, grow, mature and set in four weeks," he said.

"Once this type of invasive weed establishes, it is very hard to
control its spread. Without our biosecurity efforts, these parthenium
seeds could have spread further afield to where-ever the vehicles were
going," Mr Wilson said.

Parthenium is a registered as one of the twenty Weeds of National
Significance because of its invasive nature, potential for spread, and
economic and environmental impacts.

The weed is native to the subtropics of North and South America. Its
leaves are pale green, branched and covered with soft fine hairs.

It has small white flowers with five distinct corners. Each flower
produces several black wedge-shaped seeds that are 2mm long with thin
white scales.

"DAFWA urges local residents and travelers in the Kimberley to pay
close attention to property and vehicle hygiene. The seeds of
invasive weeds can spread very easily by vehicles, machinery, stock,
grain and fodder," Mr Wilson said.

Further information about Parthenium weed is available from DAFWA
offices in the Kimberley or by calling 1800 084 881. Information on
all Weeds of National Significance and on the Alert List species is
available at http://www.weeds.crc.org.au/publications/weed_man_guides.html

Media contact
Noel Wilson
91664001/Mob 0429 105 336
Therese Sayers /Katrina Bonser, media liaison, 9368 3937/9368 3325

PHOTO CAPTIONS:
1/ Quarantine washdown in Kununurra

2/3 A vehicle drives through flourishing Parthenium weed in
Queensland.

4/ Parthenium weed