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Eagle's-eye view: Using drones to spot invasive plants

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Researchers launched this quadcopter drone Thursday, March 23, at Memorial Park to test the effectiveness of unmanned aerial vehicles to spot the invasive Oriental bittersweet. (Photo by Michael Brun)2 / 3
Oriental bittersweet is an invasive vine that has damaged forests in southeastern Minnesota. It can be identified from native bittersweet by its yellow seed capsules on red berries. (Photo by Michael Brun)3 / 3

Researchers launched a drone March 23 from Memorial Park to test the usefulness of unmanned aerial vehicles to spot invasive plant species.

The project is part of ongoing efforts to eradicate Oriental bittersweet, a destructive vine known to smother and break trees. The plant has damaged forested areas in southeastern Minnesota, including Red Wing.

"One of the important things is to find it, so then we can go in and get rid of it," said Angela Gupta, a University of Minnesota Extension forestry educator. Drones can be deployed to areas such as bluffs and river valleys where the landscape is too challenging to search for Oriental bittersweet from the ground.

The quadcopter drone took off from Sorin's Bluff after 10 a.m. and completed a brief pre-programmed route around the area before returning to land. A camera was mounted underneath to record the flight.

Thursday's test will help determine which sensors to use, the impact of lighting conditions and how best to program the drone's flight pattern, according to the Minnesota Department of Agriculture.

The research is a joint venture by the MDA, U of M Extension, Conservation Corps Minnesota and St. Croix River Association. It is funded through an Environment and Natural Resources Trust Fund grant.

'Yell if you see yellow'

There are key differences to tell Oriental bittersweet apart from the benign native bittersweet species, Gupta said.

One way is to look at the vine's fruit; American bittersweet has orange seed capsules on red berries, while Oriental bittersweet capsules are yellow.

"So orange is OK, but give a yell if you see yellow," Gupta said.

Once located and identified, Oriental bittersweet can be controlled using herbicides.

Residents are asked to report invasive plants by calling 888-545-6684 or emailing

Michael Brun

Michael Brun joined RiverTown Multimedia at the Red Wing Republican Eagle in March 2013, covering county government, health and local events.  He is a graduate of the University of Wisconsin-River Falls journalism program.

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