Ag Explosion in Drone Use

Researchers Talk About Ways They Use UASs as Costs Come Down

Chris Clayton
By  Chris Clayton , DTN Ag Policy Editor
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Unmanned aerial systems have numerous applications in agriculture, according to university researchers. (DTN/The Progressive Farmer file photo by Jim Patrico)

MINNEAPOLIS, Minn. (DTN) -- Yong-Lak Park, an entomologist at the University of West Virginia, actually bombs invasive weeds by dropping weevils from a drone.

Park was one of several university researchers who showed how they are using unmanned aerial systems (UAS) with practical field applications at the annual meeting of agricultural science societies held this week in Minneapolis.

"What you see on the ground from agriculture may be totally different from what you can see from the sky," Park explained.

Researchers showed in presentations where they have gotten down to 1-inch imagery to spot insects or weeds affecting crops. The discussion comes as the Federal Aviation Administration is expected to roll out a plan for national UAS registration that could be announced as early as Friday.

Park and other researchers have used drones to find mile-a-minute weeds (persicaria perfoliata), which spread and smother other plants and trees with a canopy. Once they find the weeds in the West Virginia forest, the researchers create "bug bombs" that are essentially canisters of weevils that love to eat mile-a-minute weeds.

"We drop the weevils in the bug bombs and they eat the weeds," Park said.

Brian McCornack, an entomologist at Kansas State University, also has been working on how to use UASs in plant biosecurity. McCornack said there are a lot of questions about how to manage time and efficiency in using unmanned aircraft and understanding how to use different special resolutions. There's also the challenge of where to start for researchers dealing with states that have millions of acres of any given crop. Still, McCornack showed that simple imagery can highlight how crops are attacked. He noted how an extension agent walking a field missed sugar-cane aphids attacking a field just 50 feet where he had walked.

"The images can help prioritize walking routes in fields to confirm what is happening," he said.

Richard Ferguson, a soil scientist at the University of Nebraska, said researchers have been using aerial remote sensing since 1998. They started off with a large, remote-controlled hobby plane. Over time, they have moved to hovering helicopters. Nebraska researchers have been using the aircraft at heights of a meter or two above the crops to examine nitrogen and water stress in irrigated corn. Ferguson said he and his colleagues have focused on flying at low levels, partially to ensure they don't conflict with traditional aerial applicators that could be flying in the area. The challenge, he said, is finding accurate, lightweight sensors that are inexpensive.

Ian MacRae, an entomologist at the University of Minnesota, said drones with remote sensing can highlight how insects are influencing plant stress early in the process, which can translate into using less chemistry on crops. MacRae presented this information at the science meeting Wednesday morning then also was on a panel at a separate forum later in the afternoon for Field to Market.

"This technology is a game changer, and in 10 years it's going to change how we grow food," MacRae said. He added later, "You will know where to go in the field to look for stress (in the crop). That's the low-hanging fruit."

Other researchers at the science meeting discussed using unmanned systems to examine test plots as a way to help sort through plant genetic traits in crops such as wheat.

Todd Colten, chief aerospace engineer for a two-year-old Minnesota company, Sentera LLC, said his company already has flown about 12,000 hours of unmanned systems and taken more than 15 million images. The volume of data required the company to create software to automatically organize images and categorize them. He noted imagery is changing quickly as cameras become increasingly smaller. Colten said Sentera works with individual farmers, crop consultants and insurance companies looking at fields.

Colten also pointed out that roughly 40,000 drones were flown globally this past year that focused just on agricultural plots. Agriculture is expected to remain one of the biggest industries to benefit from unmanned systems, but the regulatory regime may be driven now by that rapid growth in everyday people buying such systems. "The market is here and all of this work is very useful," Colten said.


Cassandra Isackson, director of aeronautics for the Minnesota Department of Transportation, pointed out that under Minnesota law, UASs are considered commercial aircraft. Minnesota requires UAS users to register their aircraft with the state annually, which costs $100. That fee may be unique around the country, but Isackson said she speculated that state lawmakers might lower or change that fee requirement. Users must also carry liability insurance for the aircraft. Isackson said she expected to see a lot of activity in state legislatures across the country over the next year to deal with unmanned aircraft.

"Over the next six months, I think we are going to see some rapid evolution in the regulatory environment," Isackson said.

Isackson noted that until this year, UAS fliers largely operated with unfettered access because of the small volume of users. The Federal Aviation Administration this year began to revisit such rules because of the explosion in UAS use, particularly among hobbyists. The FAA projects there could be as many as 1 million lightweight drones sold over the holidays this year alone.

"We're trying to figure out what regulations need to apply and what regulations don't need to apply," Isackson said of federal and state regulators.

MacRae noted later in the day that there may already be 800,000 unmanned aircraft buzzing around the U.S. He stressed the need for anyone flying a UAS to focus on safety. "The bottom line is with this many units in the air that things are going to change," he said.

FAA has a proposed rule for regulations on UAS operations for those systems under 55 pounds in weight. Those regulations are expected to be completed next summer. FAA also has a taskforce looking at registration requirements for all unmanned aircraft. Those recommendations are expected to be released on Friday and could be implemented by Christmas to cope with the volume of drones that could fill the skies.

Isackson said users of unmanned aircraft should go to the "Know Before You Fly" website.

The FAA also has a phone app called B4UFly.…

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Chris Clayton