Corn Belt soil erosion worries continue
There's a lot of soil erosion so far this spring around Clarke McGrath. The Iowa State University (ISU) Extension field agronomist near Harlan in western Iowa says it's the worst it's been in that area about 2 decades.
It's come from a combination of factors, he says. First, rainfall has been spotty and extremely variable in that area, as it has been in many parts of the Corn Belt this spring. Long dry spells have been dotted with heavy rains, making for optimal erosion potential.
"We've had such unpredictable wild swings in weather. Rainfall, when it comes, seems to have amped itself up. We got 6 inches in 3 hours the other night. It's been coming hard and fast," he says.
So, Mother Nature's definitely done her fair share. But, so have farmers. This year's early start to spring has helped, McGrath says, but the way farmers have used their time this spring has worsened the erosion potential.
"We've done more tillage this year than any year I can remember. When we do any kinds of tillage on these highly erodible soils, it's going to loosen that soil up and it's going to make it susceptible to erosion," McGrath says.
Adds ISU agronomist and Iowa Water Center director Rick Cruse: "The opportunity for farmers to till sooner (apply anhydrous, for example in January or February) existed and that activity if coupled with heavy rains (and we have again had some) does open the door for accelerated soil erosion rates."
McGrath recommends looking into reduced tillage on farms where there's a lot of highly erodible, hilly ground. But, if you are going with either no-till or reduced tillage (McGrath recommends the former), stick to your program and avoid any additional tillage.
"It's hard for us to have a no-till system if every 4 to 6 years, we go out and tear it up," he says. "It's going to have to be long-term no-till and we're going to have to rebuild what we've done."