Sep 29, 2010
Flooding In Minnesota Could Lower U.S. Corn Yield
Author: Michael Cordonnier/Soybean & Corn Advisor, Inc.
Minnesota floods - The extensive heavy rains and flooding that occurred over much of southern Minnesota last week is going to result in crop losses throughout the region. Tens of thousands of acres of corn and soybeans (the total extent of the damage is not yet known) were flooded. In the hardest hit areas, it could be weeks before the farmers will be able to get into their fields to begin harvesting. Even in areas where the damage was less severe, it will take a week of good drying weather to firm up the soils enough for harvesting to commence.
The floods hit the best areas of Minnesota where high yields were expected to compensate for some of the problems encountered in the eastern Corn Belt.
Potential problems for corn - There are several potential problems for the corn fields that experienced the flooding. The biggest problem is going to be moldy corn. If mature corn ears are exposed to flood waters for any period of time, a variety of molds can colonize the ear. These molds can lower the test weight, cause significant dockage at the elevator, or even make the ear un-harvestable and the corn unsellable. It is entirely possible that many of the fields that experienced the worst flooding will not even be harvested at all because there will not be anyplace that will accept the corn except for maybe ethanol plants and even that might be questionable.
Another problem for the corn is going to be standability. Diseases and molds are also going to start attacking the corn stalks which could result in additional stalk breakage and eventually greater harvest losses.
If Minnesota lost 10% of their corn crop due to last week's heavy rains and flooding, this would be a huge loss indeed that would equate to nearly a one bushel reduction of the nationwide corn yield. The total extent of the damage in Minnesota remains to be seen, but I think it will be enough to trim the U.S. corn yields a little more.
Potential problems for soybeans - A lot of bad things can happen to soybeans if a mature crop is exposed to extensive flooding. Problems for soybeans could include: soybeans absorbing water and sprouting, pods splitting open, shatter loss at harvest, and soybeans turning moldy. Once a soybean seed is mature, it will start to swell and sprout anytime it is exposed to extensive periods of moisture thus making the seed un-harvestable. If soybean pods are in water and then dry out quickly afterwards, they tend to split open dropping the seeds on the ground. These brittle pods are then more susceptible to shattering during harvesting. The vibration of the cutter bar cutting the soybean plant can cause the pods to shatter and spill the seeds on the ground before they can be taken into the combine.
Additionally, extensive wetness and flooding once the crop is mature is going to result in moldy soybeans. A fungal disease called Pod and Stem Blight invades the seeds if they are exposed to repeated cycles of wetting and drying once the seeds are mature. The seeds end up being small, shriveled, moldy, and light in weight which allows them to be blown out the back of the combine or screened out at the grain elevator.
The soybean crop in Minnesota is also going to suffer losses due to the flooding (maybe even more than the corn percentage wise), and the losses in Minnesota could also result in a lower U.S. soybean yield.