The aim of the research was to determine if the UAV imagery could monitor the grass weed populations across seasons in crops and pastures, if resistant weed patches were continually in the same area of the paddock and if the information could be useful for farmers to adopt this method to better target grass weed control.

• UAV imagery with skilled specialist analysis has the potential to identify weed issues in paddocks.
• It was easier to identify grass weed patches in legume and pasture crops than cereal crops.
• Data capture and analysis for analytical purposes such as grass weed mapping in individual paddocks will be beyond most farm enterprises unless farmers have a special interest in this area.
• Grass patches were more reliably identified using UAV data captured at higher resolutions.
• Barley grass resistance to Group A herbicides has been detected several times throughout the project, so be aware it may be present in current farming systems.