Field scouting by drone gets practical
According to a 2014-16 study, an Unmanned Aerial Vehicle could be a handy addition to your farm equipment line-up.
Before crop producers apply a herbicide, fungicide or insecticide, standard practice is to walk or drive by the field to scout for weeds, disease or insects.
According to Chris Neeser, Brooks-based Weed Research Scientist with Alberta Agriculture and Forestry, this has become less and less practical for producers as farms have increased in size.
“There’s only so much time in a day,” Neeser said. “You can hire a crop consultant, but even then, 10 to 15 quarter-sections per day is probably the most anyone can do and still call it crop scouting.”
Five or so years ago, ag manufacturers started coming to market with Unmanned Aerial Vehicles – also known as drones. These have been marketed to crop producers as a way to gather images from the sky for crop scouting. However, the question of whether the cost of obtaining imagery and is it accurate enough to replace boots in the field needed to be determined.
A 2014-16 study led by Neeser, funded by Alberta Pulse Growers through the Alberta Crop Industry Development Fund, investigated the agronomy and economics of scouting-by-drone.
Limited potential for weed scouting
The drone is only part of what’s needed to scout from the sky. A camera and accompanying software is needed to take aerial images and stitch these together to give a single view of a field at a resolution that enables the analysis are the keys to effective use of this technology.
After three growing seasons working with five crop consultants, gathering and interpreting aerial images of southern Alberta crops, Neeser gives drones a mixed review.
“We found the resolution that’s available is not enough to detect small things like weeds,” he said. “Weeds also tend not to change much in one area from year to year. You can see an area where the crop’s not growing well, and that could alert you to go out there and check for disease. So it could be a kind of pre-scouting system.”
The drone set-up used by Neeser cost $3,000. At that price, and figuring on time spent travelling to and from clients’ fields, a crop consultant would need to charge $40 per acre to be profitable. As with many newer technologies, however, the farm-based UAV is already coming down in price. A unit far better than the one used by Neeser now costs 50% less.
Despite its apparent limitations for weed scouting, Neeser believes many farmers will like the idea of aerial trouble-shooting, whether for disease or issues like salinity or poor drainage. Rather than pay a consultant, they might just keep one in the shed and use it as a time-saving agronomic convenience.
“You might think of it as kind of an ad hoc tool you can use in many ways,” Neeser said. “Actually, the real future is newer ideas that are coming along, like using aerial robots that allow you to do even more, like go out and spot-spray for you.”