By Dennis Chaptman
This map looking at soybean crops in the Upper Midwest shows how yields are predicted to vary even within the same county. Researchers are trying to verify their estimates by working with farmers to determine their actual yields.
Images captured from satellites orbiting 440 miles above the Earth tell a powerful, richly detailed story about crop yields—revealing the lushness or deficits of fields with surprising precision.
With the help of about 100 farmers so far as part of a citizen science project, researcher Phil Townsend and his team hope to coax even more valuable information from the satellite photos and change how farmers’ yields are reported and analyzed.
“The reporting of crop yields is now done at the county level with information confidentially reported by farmers to the USDA,” says Townsend, a professor of forest and wildlife ecology. “Counties can be very large. We now have the ability to analyze yields at the field level with these images, giving us much more accurate and granular data.”
By tracking the greenness of fields from the satellites and analyzing climate data, researchers hope to identify impacts of insect pests, crop diseases and weather events like frost, tornados or hail.
First, however, they needed to test their yield estimates against farmers’ actual yields. So Townsend’s team developed a website—yieldsurvey. wisc.edu—that allows researchers to confidentially crowdsource crop yield information. Townsend is encouraging even more submissions.
Farmers can enter their field’s location by dropping pins on a Google map, along with the type of crop and the actual crop yield for as many seasons as possible. The information is then analyzed and compared to estimates developed in Townsend’s lab.
“Our yield estimates are within about 15 percent of what the farmers report,” Townsend says. “Our target is to get that down to 10 percent. If you’re a farmer, the closer you can get to that could be the difference between making money and breaking even.”
Citizen science is a two-way street—it helps researchers tweak their estimates based on real data, and those more accurate numbers can help farmers be more productive and better managers.
Ultimately, Townsend says, the satellite technology and climate data, refined by knowing the actual yields from participating farmers, have the potential to predict crop yields well before harvest time.
Farmers see promise in the new approach, says Kevin Erb, a UW–Extension agronomist based in Green Bay.
“Farmers benefit from using remote sensing technology,” Erb says. “If we know early in the season that we have the potential for above-average yields, that can affect the types of pesticides and fertilizers that you use during the season.”
Being able to make decisions during the season based on this sort of predictive data could increase profits $50 or more per acre, Erb says.
Townsend’s team is cooperating with the USDA and hopes to snag funding to broaden the project. The effort is an example of the Wisconsin Idea at work, Townsend says.
“We have to connect with our constituents, and that’s where crowdsourcing and citizen science comes into play,” he says. “Farmers are participating in the science, and they see the benefits. It’s building trust.”