Midwest U.S. growers with flooded fields may find that soils have been damaged too much to plant this year even if the waters recede quickly, say agronomists.
Reuters reports that fields that have been underwater for close to a week were facing damage that could give growers headaches for years. About 20 percent of Iowa’s corn crop was either ruined or is in serious jeopardy, Iowa State University agronomist Roger Elmore says. The remaining 80 percent is not in good shape.
"There has been a tremendous amount of soil erosion," says James Fawcett, a field specialist in southeastern Iowa with Iowa State Extension Service. "The fields will not be as productive as they have been in the past."
Fields along flooded rivers will have to be cleared of sand and debris before they can be planted again, Fawcett adds. And it will take a long time for some fields to dry even if the standing water subsides soon.
But conditions have dried out enough on higher ground to allow some growers to replant soybeans or spray and fertilize their fields despite watery "potholes," says agronomists like Palle Pedersen, Extension agronomist at Iowa State University.
About 20 percent of Iowa’s corn crop was either ruined or is in serious jeopardy, Iowa State University agronomist Roger Elmore says. The remaining 80 percent is not in good shape.
Affected growers face a dilemma: spend the money to replant and reap perhaps half the normal yield, assuming there is not a summer drought or early frost, or accept crop insurance payments.
Growers that are able to replant fields that have been damaged by the flooding were taking a risk that yields will be severely reduced due to the late planting date. "For sure, they are out on a limb with this crop," says Emerson Nafziger, Extension agronomist at the University of Illinois.
Any corn planting that can be done immediately faces yield reductions of 50 percent or more due to the shortened growing season for those plants. Normally, corn planted in central Illinois and Iowa after May 15 loses about a bushel of yield per acre each day. But flooding has also washed out nitrogen fertilizer, a key corn-yield booster, from planted fields. Corn also can be damaged if it does not reach the crucial pollination phase before scorching summer temperatures arrive.
But even if fields are dry enough, growers cannot just switch intended corn acres to soybeans, which can be planted until the end of the first week of July, Reuters notes. Many growers have applied herbicides to fields where they had planned to plant corn. Those herbicides can be harmful to soybeans, so growers may have to let those fields remain bare for this season.