Weed management: towards the underground movement

Weed management is in continual evolution. In the early days of agriculture in Australia, weed control was addressed by cultivation. However the soils were not robust enough for this treatment and, together with the major infestation of skeleton weed, farmers were forced to introduce a pasture phase. There were major successes for biological control, notably prickly pear and skeleton weed, but it has been slow to work on Paterson’s curse and is not an option for annual ryegrass. Chemical control has been at the forefront of weed management for three decades now. However evolution of herbicide resistance, particularly in annual ryegrass, raises questions about herbicide management and the future of “chemical farmingâ€�. We therefore need to broaden our approach and look for other options, one of which is using the chemical interactions that occur naturally in plant communities. Known as allelopathy, this interaction is receiving greater attention in understanding invasiveness of weeds and as a tool to reduce our dependence on herbicides. These options are explored in the paper.