Farming Prairie Potholes
The landscape of the Upper Midwest is pockmarked with prairie potholes, thanks to glaciers that scraped out the area centuries ago. The potholes fill with snowmelt and rain. Some will eventually drain, but some don’t which has detrimental effects on both early and late crops in a farm field. Research has shown that farmed prairie potholes lose money more often than they make a profit.
Amy Kaleita is an agricultural and biosystems engineering professor at Iowa State University who is studying prairie potholes. She says if you have problems with them, think about things you can do that will improve the infiltration and water holding capacity of the soil.
"Switching to a more conservative tillage or to a no-till situation. That’s going to improve the drainage of the whole field so that you don’t have as much runoff coming into the pothole," says Kaleita. "Another thing that we might think about is adding subsurface drainage. But, the potholes that we’ve been studying have illustrated that subsurface drainage helps, but it doesn’t reduce all the problems related to trying to grow a crop in a pothole."
Another option is to simply wave the white flag and retire the pothole.
"In some places we’ve seen if the conditions are right, enrolling them in the CRP program," she says. "Other people have said, this area is a nuisance and it’s interfering with the rest of my operation so I’m just not going to plant there. And they’re just doing it in grass on their own. That’s particularly easy to do if the pothole happens to be closer to the edge of the field and it’s really easy to just kind of cut that area out of production."