Exploring Aerial Imagery in Precision Ag
On a sunny day this summer, Austin Bontrager spent his morning on the edge of corn and milo fields. His task for the day was to fly an unmanned aerial vehicle (UAV) over the fields for one of his producers.
He programmed a flight plan for the UAV into his computer.
Once the programming was complete, Bontrager - an Agronomic Technology Support Specialist based out of Nebraska - checked the wind speed online. He then picked up a handful of dirt, and noted that the wind direction was slightly different than what the forecast suggested. He looked out for crop dusters in the area, and noted a nearby humming sound that could indicate a small plane nearby.
It takes a surprising amount of manpower to fly UAVs, Bontrager said, and they aren’t going to replace agronomists anytime soon.
“I think (UAVs) will make a more efficient use of the agronomist’s time to see where they should focus when they’re out in the field,” Bontrager said.
The UAV is made of Styrofoam and weighs less than five pounds. Once the programming was complete, Bontrager launched the UAV by throwing it in the air. The flight will last about 40 minutes, he said, and for the most part, the UAV will fly itself.
A few years ago, Servi-Tech started looking into satellite imagery as a tool to identify areas of stress in fields. The service wasn’t reliable, the resolution was low, and cloud cover was often an issue.
This year, Servi-Tech started delving more in-depth into UAVs and manned aircraft for aerial imagery. Each has its pros and cons.
Servi-Tech does offer manned flights for aerial imagery. Producers and retailers can sign up for that service with their agronomist.
Manned aircraft can cover a large number of acres in a short period of time. It doesn’t require Servi-Tech to buy equipment, to do training, or hire additional staff. A commercial pilot takes photos and delivers those photos to a cloud-based service.
“It’s simple and convenient,” said Ryan Meister, Servi-Tech Expanded Premium Services' director of technology development. “We can get good quality photos from 3,500 feet.”
UAV technology also has its perks. Drones are more flexible about weather conditions and can fly under cloud cover. However, it takes a significant amount of computer processing time to stitch 1,800 images together that are taken 300 feet above a field.
Additionally, drones can only fly for 30 to 40 minutes per battery, which limits the amount of acres covered in a day. With a manned aircraft, Meister said, thousands of acres can be covered in a day.
Meister said at the moment, aerial images from manned aircraft are more economical for growers.
Servi-Tech is exploring the UAV flights, but it’s more of a trial period for the company, said Bontrager. Current FAA regulations prevent companies from marketing drone services.
Bontrager and Meister said there’s still quite a bit of work to do before Servi-Tech offers aerial imagery for all of its growers.
“In 10 years, I’m not sure what’s going to be the most widely used,” Meister said. “From the standpoint of agronomy and consulting, it doesn’t really matter as long as we get good information in a timely matter.”
Aerial imagery offers another viewpoint that can help an agronomist identify issues in fields. Bontrager said he doesn’t anticipate aerial images replacing agronomists who check fields.
“It’s hard to tell in the field where heavy hit parts are when it comes to hail damage, wind damage and green snap,” Bontrager said. “If the crop is laid over, that’ll show up on imagery and let the agronomist know where they need to go to see how bad the damage is overall.”
Bontrager said he enjoys working and experimenting with the technology behind aerial imaging.
“It’s always interesting to look at that data as it comes in,” he said.
So far, Servi-Tech has been able to identify field compaction, nutrient deficiencies and differences in irrigation patterns in fields with aerial imagery. Insects and disease pressure are harder to identify from the air, but are also possible.
Bontrager said he’s interested in seeing if grey leaf spot shows up in imagery later in the growing season.
The work of experimenting with aerial imagery is not done. As the technology gets better, it will become more affordable and easier to get, Meister said.
“We’ll do more next year, look at different things, and look at different things this year,” he said. “It’s kind of a work in progress.”
For more information about aerial imagery, contact Meister at firstname.lastname@example.org