Organic farming meets hi-tech monitoring
In 1989 Jean Hediger’s 25 hectare family farm near Fort Collins became one of Colorado’s first certified organic growers.
A quarter of a century later and three generations of her family farm 1,400 hectares in the high plains of eastern Colorado as well as working with over a dozen growers cultivating more than 4,000 hectares to market organic grains through the family’s Golden Prairie marketing and distribution company.
Needless to say, her credentials as an expert agriculturalist are under no doubt, so when Colorado technology incubator Innosphere was looking for a farm to team up with fledgling drone company Agribotix she was an obvious choice. The precision agriculture firm was formed in December 2013 to explore the potential of using drone-based aerial imaging to give farmers on demand information about their crops.
While Agribotix was sure the imagery would prove useful to farmers, exactly how was still unclear. They would also face a hard sell to conservative farmers without solid data to back up their claims. “Now the whole industry is talking a lot more about drones, but a year ago it was really ground-breaking,” says Hediger. “Not every farmer at that time would let people come and take pictures of their fields.”
Luckily for Agribotix the Hedigers were forward thinking and agreed to let the firm fly their drones over their fields last summer in return for free data and analysis. The firm used its fixed-wing Hornet drone, which is based on the RV Jet airframe from RangeVideo and fitted with consumer-grade Canon S100 and GoPro cameras modified with high quality non-distorting lenses and near-infrared (NIR) filters.
A picture is worth a thousand words
The NIR images it takes are used to create field health maps to a resolution of 30cm using the normalised difference vegetation index (NDVI) developed by Nasa in the 1970s. The technique relies on the fact that plants are unable to use NIR light for photosynthesis so their leaves reflect these wavelengths to prevent them from drying out.
Agribotix already knew that if the cameras picked up a strong NIR signal it denoted more or bigger leaves and therefore good crop growth, whereas a low signal suggested poor growth. How exactly this information, as well as conventional imagery taken by the drones, could be useful to farmers was less clear.
“We had no expectations whatsoever, but very quickly we saw how they would be able to help us,” says Hediger. “It’s very important being able to get a wide-view of our fields. It tells us where they’re dry; it tells us where the plants are thinning out; what the yields might be; it might tell us where there are insects; all things you can’t see on large farms because you can’t drive through it as you will damage the crops.”
A particular concern for organic farmers is perennial weeds, due to the fact that they are not allowed to use herbicides. Each year the weeds spread until they begin to affect the productivity of the field. Eventually the farmer has to apply herbicide to control them, but they then have to take the field out of organic production for four years until traces of the herbicide are gone.
“Last year we had a couple of hundred acres we were thinking we had to take out of organic production because of perennial weeds, but after the information from Agribotix we realised it wasn’t as bad as we initially thought,” says Hediger. “Being able to keep them in organic production this year means we visualise three times the value on the crop.”
Drones are not the only way of getting aerial imagery of course, but one thing they hold over rival technologies is responsiveness. Most satellite systems only pass over a field once every 15 days or so and cloud cover, a common occurrence in the US Mid-West, means most fields are only visible roughly once a month. Manned aircraft are capable of carrying out the same imaging, but to make it cost competitive each flight has to cover a far greater number of fields.
“With drones you can get information every day, you can even get information multiple times a day,” says Hediger. “If it rains and you want to know how it’s affected your fields 12 hours later you can have a drone fly over and monitor it. A drone can go in 10 minutes after a hail storm and appraise the damage.”
One disadvantage, however, is the regulatory environment in the USA. According to Agribotix founder Tom McKinnon the company has had success selling its hardware and backend image processing services across the globe, but tapping the domestic market has been made tough by the “adversarial” approach of the Federal Aviation Authority (FAA).
“It’s worse than stifling us,” he says. “It’s almost crushing us in the US in terms of getting customers and getting investors.” With regulations “up in the air” last year, McKinnon says the company relied on “workarounds” to the FAA’s blanket ban on commercial drone operations, including flying for free for customers like the Hedigers.
This year they have hired a consultant to apply for an exemption to the ban, but with most of the 700 pending applications ahead of them in the queue and no guidance on what is required for a successful application there is no guarantee they will get approval in time for the coming growing season.
An evolving landscape
New rules proposed by the FAA in February could smooth the process considerably, drastically reducing paperwork and removing the requirement for drone manufacturers to go through the rigorous airworthiness certificate approval process for their airframes. They will also remove the requirement for operators to hold a private pilot’s licence that has not been made explicit, but has been present in all successful applications so far.
Operators would still need to undergo roughly 40 hours of training and stick to the current restrictions – operating below 400ft (122m), at least 5 miles (8km) from an airport, during daylight, away from the public and within line of sight – but McKinnon is hopeful the changes will come in soon and open up the domestic market.
Once it does, he is optimistic that farmers will see the benefit of the highly accurate information services like his can provide. “Farmers are great economist. They’re always looking at the bottom line, always increasing yields and reducing inputs. They’re always running the calculations in their heads,” he says.
The firm already has a few paying customers in the US, but for the Hedigers the calculation didn’t add up. They’ve decided Agribotix’s prices don’t fit their business model, but they have been inspired by the joint project. This year they bought themselves a Phantom 2 drone from Chinese manufacturer DJI and fitted it with a standard GoPro camera to monitor their fields themselves.
“What we are doing is very elementary compared to what they can do. Agribotix has a Buggatti, we have an old Volkswagen Bug!” says Hediger. “But what they were able to do is show us the value of using drones.”