NQ Dry Tropics – Siam Weed

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June 2014 – Siam Weed

NQ UAV was approached by NQ Dry Tropics to develop a methodology to help in the detection of Siam Weed (considered one of the world’s most invasive weeds). Siam proliferates in a variety of environments such as rainforest and steep river gullies where it is often hard to reach by land based vehicles.

Siam Weed (Chromolaena odorata) was under a national eradication program from 1994 to  2013 where the use of helicopters for aerial surveillance was an essential part of the program. In 2014, post eradication and in a transition to management phase, the available funding and expertise for helicopter surveys was no longer readily available despite the fact that some of these Siam Weed infestations required active monitoring to prevent further spread.

To overcome this hurdle NQ UAV and NQ Dry Tropics worked together to trial the use of unmanned aerial photography for use in detection and monitoring. Data sets produced by the  UAVs/Drones/RPAs can also be used as a training tool for approved helicopter personnel.

The initial test sites were chosen in the Bluewater area, just north of Townsville. This area had been extensively ground truthed and GPS referenced during the Siam Weed eradication program. It also presented an easily accessible site for both NQ UAV and NQ Dry Tropics to operate in.

The flight, using a fixed wing UAV, was planned to occur at the peak flowering period (May-June) to maximise the volume of Siam detected with the standard lens. Due to delays, the trial was not completed in Bluewater due an extensive delay from CASA in response to an application of exemption. This time delay was not factored in during our planning phase and compromised the timing to coincide with peak flowering. We were able to source another site closeby which also provided georeferenced and ground truthed Siam Weed locations.

In conclusion, the trial proved to be successful in providing visual detection of Siam Weed in the dry tropical landscape. We extended the trial to include the use of multi rotors to asses the best range for positive detection. During these trials we were also able to positively identify Lantana (Lantana Camara), another invasive weed.

This research project undertaken with NQ Dry Tropics provided the foundation for future work in this growing field. The results indicate that aerial detection from unmanned platforms for invasive species such as Siam Weed is possible and at altitudes which most RPS can fly at. We hope to continue this work to determine the best altitudes to fly at in order to detect, identify and plan strategies to manage for the spread of Siam Weed and other invasive species..

For more information on this project, contact Byron Kearns from NQ Dry Tropics