Sugar could be an innovative alternative to herbicides and curb one of agriculture’s costly scourges, annual weeds.

 

In a three year project by researchers from Charles Sturt University’s Institute for Land, Water and Society, sugar spread on plots in central NSW was found to effectively inhibit or “starve” the growth of annual weeds, making way for the native grasslands to flourish.

 

“In our trials conducted on a private property and a travelling stock reserve near the NSW town of Young, sugar provided an effective, short-term, ecologically friendly method of weed control,” said a member of the CSU research team and ecologist Dr Ian Lunt.

 

“Our earlier research has shown that many of our annual weed problems are due to high nutrient levels,” said research leader and Senior Research Fellow at the Institute for Land, Water and Society, Dr Suzanne Prober.

 

In the project funded by the NSW Environmental Trust, the sugar fed soil micro organisms, which then absorbed soil nutrients. This “starved” the weed species which need these nutrients to grow.

 

“We realise that it would not be economical to use the sugar levels we used in our trials,” said Dr Prober. “However, at the moment we don’t know if we would get similar results if we used less sugar or if we used cheaper alternatives such as molasses or sawdust.”

 

“We see what we have done so far as only part of the picture,” said Dr Prober. “Our long term goal is to work out the best methods for re-establishing a native ecosystem that is diverse, self-sustaining and resistant to invasion by weeds.”

 

The researchers are aware their work could be the basis for other more agriculturally driven studies.

 

“Annual weeds such as Wild Oats and Paterson’s Curse are the bane of every farmer’s life,” said Dr Lunt. “Sugar may help land managers to control annual weeds and reintroduce native perennials.”

 

“Our trials have demonstrated an enormous potential to use sugar to help restore degraded, weedy woodlands. We are now seeking further funds to develop large-scale, cost-effective techniques to tap this potential,” concluded Dr Lunt.