ScienceDaily: Weeds cost Australia more than A$4 billion a year either in control or lost production and cause serious damage to the environment. In an address given April 15 in Perth to the Greenhouse 09 conference on climate change, CSIRO researcher, Dr John Scott, said, however, that those cost estimates were only based on the damage caused by weeds known to be active in Australia. “Out there, throughout the nation, are many weed species lying low but with the potential to take off and …