In the past, many single factor studies have demonstrated the effectiveness of cultural weed control tactics in decreasing weed biomass and seed production in Australia. However, these studies have largely failed to integrate multiple weed control tactics in a single study. Herbicides remain the primary and most efficient method of controlling weeds and so there is a need to study factorial combinations of effective cultural and herbicide tactics across different rainfall zones.

The overall aim of this project is to quantify the effect of combinations of crop competition factors on weed seed-set and crop yield, to refine strategies and improve crop competitiveness across different rainfall environments in southern and western regions of Australia. This aim will be achieved through the integration of ecologically appropriate cultural practices that increase crop competitiveness against weeds, such as time of sowing, crop density, nitrogen placement and seed size. It is proposed to investigate cultural weed management of two weed species (southern: annual ryegrass and brome grass; western: annual ryegrass and wild radish) in major crop species (southern region: wheat, barley, canola and faba bean; western region: wheat, oats, canola).