Fire Destroys Weed and Saves Biodiversity

Scientists have developed a new environmentally-friendly way of killing boneseed, a weed listed among Australia’s top twenty “Weeds of National Significance”.

The new methods combines controlled fires, herbicides and revegetation, and replace the old ‘hit or miss’ method that threatened to wipe out rare and endangered plant species as it killed the boneseed.

Rachel Melland, a PhD student with the CRC for Weed Management in Adelaide, said her method uses native grasses as a weapon against this invading plant.

“We are now able to restore native biodiversity to areas which are currently being wiped out by boneseed,” she says.  “After the fire has burnt out existing boneseed, new native grass growth chokes the weed out and stops it re-establishing.”

Ms Melland is presenting her findings today (Thursday) at the Exhibition Centre, Melbourne, as one of the Fresh Scientists at ScienceNOW!

She described boneseed as a shrub with yellow daisy flowers, and says it was a popular garden plant 150 years ago when it was brought into Australia .

“But then it escaped into the wild, and now crowds out thousands of hectares of native flora and fauna.  It’s a devastating environmental weed, and we all need to be more aware of the dangers of growing new weedy plants,” she says.

Weeds infest both native and agricultural ecosystems and can be grasses, garden flowers, woody shrubs or trees.

CRC Director Associate Professor Rick Roush says, “Landowners and conservation workers are often nervous about using fire, both because of the potential effects on native species and concern that a fire will escape to damage to surrounding property.

“But legal, controllable fires can be a powerful weapon in the war against boneseed and other weeds.”

“And even for wild fires  can provide a silver lining.  No one would ever endorse wild fires, but they do provide a unique opportunity to get on top of weeds if properly followed up,” adds Roush.

*** “We are introducing biocontrols for  boneseed, such as the boneseed leaf roller, but it will take some years for these insects to really take effect. Even then, they are probably most effective against young plants and may need help by integration with other controls.  This project shows how fire can be used to destroy mature plants.

Ms Melland adds, “We have a lot of gorgeous native plants in Australia, I would like my future grandchildren to be able to see those plants rather than a sea of weeds”.

Weed websites

Weeds of National Significance (WONS) and noxious weeds list:

Vision opportunities

Presentation by Rachel Melland on May 4th 2000 at 11.30am at Exhibition Centre…….. Opportunities to get shots of ‘Woody the Weed’ (life-size mascot) and large live boneseed plants. Boneseed seeds will also be available with the new biological agent, the Leaf Roller Moth.

Related Articles