This past weekend, southern Minnesota once again got an extreme example of how quickly the wrath of Mother Nature can change things. From early Saturday morning to Sunday evening, many portions of southern Minnesota received 5-12 in. of rain, or more, with portions of southeast Minnesota receiving over 15 in. There was human tragedy, numerous reports of property damage and considerable damage to roads and infrastructure in several southeastern Minnesota counties. While most of the state and national stories focused on the damage in the cities and small towns, there is bound to be millions of dollars of loss and damage on farms and related to agriculture. A majority of farms in extreme southeast Minnesota are on hillsides and have rivers or small creeks running through them. There is likely considerable property damage, loss of livestock and damage to crops on farms in the region.

It is too early to know the impacts on crops from the extremely heavy rains in southern Minnesota. Many times the damage from the heavy rains late in the growing season is hidden by the growing crops; however, there still can be considerable damage to crops. Long-term standing water in fields can prematurely end the growth of healthy plants, thus causing yield reductions. The standing water can also cause the inset of stalk diseases in corn and stem diseases in soybeans, causing plants to lodge, which can lead to harvest problems. In addition, the standing water may recede at a much slower pace in late August and early September, due to lower evaporation rates, shorter day length and less water requirements by growing plants. If wet weather patterns continue into September, there could be issues with being able to harvest crops on a timely basis in some fields in parts of southern Minnesota. The area with 5 in. or more of rainfall this past weekend covered many portions of the southern third of Minnesota, so the impact on crops could be quite widespread.

Beyond the potential crop damage and future harvest problems, the recent rainfall was beneficial to soybeans in most areas, and should help add some extra yield to soybeans that were not severely drought damaged, and were not impacted by the standing water from the weekend storms. The rainfall should also help the drought-stressed corn mature more naturally, which will not likely add much to the final yield of the corn, but should help maintain good test weight on the corn. The rainfall will also be beneficial to help replenish depleted supplies of stored soil moisture, and should help restore pastures and alfalfa fields in the extremely dry areas of southwest and south-central Minnesota.

Comparisons to 1976
Many residents of southern Minnesota remember 1976, the bicentennial year, which was also the year of the major week-long major Farmfest event west of Lake Crystal. In 1976, crops were planted early and were doing great into June, then it turned very hot and dry in July and August with drought conditions, resulting in considerable yield reductions to crops, especially to corn. In early September on the first day of the bicentennial Farmfest event, 5-7 in. of rain fell in a short period of time, followed by several more inches of rain in the following days, which led to considerable flooding and damage to crops. Sound familiar?

Actually, even before the heavy rains this past weekend, many weather observers had compared the 2007 weather patterns to 1976, when the drought in the U.S. was centralized over eastern South Dakota, northwest Iowa, southwest and south-central Minnesota, into central and northern Minnesota. The drought pattern in 1976 was very similar to this year. The comparisons of 1976 and 2007 are like to continue as we head into harvest season.

Editor’s note: Kent Thiesse is a former University of Minnesota Extension educator and now is Vice President of MinnStar Bank, Lake Crystal, MN. You can contact him at 507-726-2137 or via e-mail at kent.thiesse@minnstarbank.com.