Using the 'OWL' for weed management

North West Local Land Services is working on a low cost spot sprayer originally developed Sydney University. Using low cost readily available components the unit uses software to detect green plant material in fallow paddocks (green on brown) which in turn triggers the appropriate spray nozzle.

The unit has been named the 'OWL' or Open Weed Locator reflecting the fact that the university has made the technology available to everyone and potentially could be used not just for spray booms but for other weed control options such as hydraulically controlled tynes.

Increasing herbicide resistance means that all potential tools to decrease weed numbers need to be considered and the OWL project could provide a route to lower cost spot sprayers that may be suitable for smaller growers. It is hoped that ongoing development will eventually result in higher operation speeds and development of a 'green on green' model which can detect weeds within a growing crop.

The components for the detection units cost around $450 with one being required for every metre of boom. After that the additional costs include boom construction and individual solenoids for each nozzle. A number of algorithms were tested initially and the final software is available for all on the OWL website. So far detection accuracy has been good although some discoloured weeds and very small weeds with narrow leaves may be missed.

The OWL website also provides instructions on building the units, plans to enable 3D printing of the housing boxes and discussion forum for users.

Further information can be found at https://github.com/geezacoleman/OpenWeedLocator