From the road, soybean fields often look good during most of the season. But what do they look like from the air? If you could fly like a bird, what would you see?
Steve Gauck doesn’t have wings and isn’t aerodynamic, but his DJI Phantom 4 UAV meets those requirements. He uses the unmanned aerial vehicle to get a more complete picture of what’s going on in the field compared to what you can see just standing along the edge.
“If there are blemishes in a field, they will show up once we fly the drone over it,” says Gauck, a regional agronomy manager for Beck’s. The seed company sponsors Soybean Watch ’20.
Gauck passed the test required by the Federal Aviation Administration to fly his drone for crop scouting purposes and maintains his license. His ability to fly the drone over this year’s Soybean Watch field came in especially handy since the back half of the field is hidden by a large hill running across the entire middle section of the field.
“The field looked good all season from the front side,” Gauck says. “And other than being planted late due to wet conditions, it appeared to have good yield potential.
“After flying the drone over it and seeing the back half of the field, we dropped our expectations just a bit. They were still good soybeans, but some blemishes showed up that weren’t visible standing on the other side of the hill. Even if there wasn’t a hill in the way, the blemishes we saw wouldn’t have stood out as clearly just scouting on the ground. The beauty of having access to a drone is that you can get a view from the air and see a more complete picture of what’s happening in the field.”
Here are the blemishes that became evident thanks to the drone flights:
Vole holes. Bare spots scattered across the back half of the field were due to feeding by voles, and perhaps moles, earlier in the season. “We diagnosed it on an earlier visit,” Gauck notes. “When they appear in fields, they usually wipe out anything in sight within small areas near their burrows. If you add up all the area affected, it’s not a huge amount, but it might knock off some bushels here and there.”
Weed patches. The bright green, circular patch in the lower center of the picture is a weed patch. “We flew at a lower altitude and determined it was a patch of Canada thistles,” Gauck says. “The field was irrigated, and moisture was apparently fueling their growth in early fall.”
Replant areas. The long, narrow green strip near the end rows of the field represents soybeans that were replanted by spotting in later after most of the field had emerged. They lagged behind in maturity as the season drew to a close.
Maturity differences. Two varieties were planted side by side across the field. Although they only varied by about 0.2 group units — one being a 3.5 and one a 3.7 variety — the difference seemed larger than normal when this photo was taken Oct. 1. “We’re still trying to explain why later varieties seemed to mature slower in 2020,” Gauck says.
Irrigation tracks. The cost is minor compared to the benefit, but irrigation tires leave tracks, more like narrow ruts, as noted in the circular pattern in the photo.