Excessive Rainfall Results in Crop Loss

July 2, 2018


The old saying “rain makes grain” may hold true in many instances, but this year excessive amounts of rainfall early in the growing season has caused extensive crop loss in some areas. Large portions of Southwest and South Central Minnesota, along with adjoining areas of Northern Iowa, and Eastern South Dakota have been impacted by severe storms and excessive rainfall amounts during the last half of June. This has caused considerable drown-out areas in fields, as well as crop damage to the remaining crop in many fields. As of June 29, many rivers across Southern Minnesota were above flood stage, closing roads and flooding farm fields. So, some farm operators with flood plain farm land that avoided the initial crop loss following the heavy rainfall events, are now experiencing major flooding and crop loss due to the rising rivers and streams.

Most of the affected region received 150 to 200 percent, or more, of their normal rainfall amounts for the month of June, with much of that precipitation coming since the middle of the month. Some locations in the region have received 10-15 inches of rain during the month of June, and have now nearly doubled their annual precipitation for the first six months of the year. In some areas of extreme Southern Minnesota and Northern Iowa, farm operators had not completed their 2018 corn and soybean planting prior to the heavy rainfall events in June.

As of June 27, the University of Minnesota Research and Outreach Center at Waseca had 5.78 inches of rainfall in June, which compares to a normal average June rainfall of 4.66 inches. The U of M Research and Outreach Center at Lamberton recorded 7.19 inches by June 27. Many portions of Southwest and South Central Minnesota have received much higher total rainfall amounts during June.

A major concern that is developing as a result of the excessive levels of June rainfall is the loss or lack of available nitrogen for the growing corn. Much of the nitrogen fertilizer for the 2018 corn crop was applied last Fall or early this Spring, prior to planting. Soil nitrogen losses increase substantially during heavy rainfall events early in the growing season, such as have occurred in the past few weeks. Many corn plants have developed very shallow root systems, which have not been able to access the nitrogen that is deeper in the soil profile. In some cases, farmers planned to side dress the nitrogen after planting, but have been unable to do so due to the continual saturated field conditions. Some growers may need to consider supplemental nitrogen applications to maintain normal crop development.

Another concern with the persistent wet field conditions is timely herbicide applications for weed control. Producers that were relying totally on post-emergence herbicides for weed control have had difficulty getting these products applied in a timely fashion, which is resulting in strong weed pressure in some fields. We have already passed the time window for dicamba herbicide in soybeans, as well as for some other post-emergence herbicides used in corn and soybeans. Producers should contact their agronomist or crop consultant for further considerations regarding additional nitrogen for the 2018 corn crop, as well as for late season post-emergence herbicide options for this year’s crop.

Other than the heavy rainfall events, most of June has featured normal or above normal temperatures, which has allowed for rapid development of corn and soybeans in many areas of the Upper Midwest. As of June 27, the accumulated growing degree units (GDU’s) at Waseca since May 1 were at 997 GDU’s, which is approximately 23 percent ahead of normal. The weekly USDA Crop Condition Report on June 25 listed 84 percent of Minnesota’s corn crop and 79 percent of the soybeans as “good to excellent”; however, that crop rating has been declining in the past few weeks.


Crop Insurance Considerations

Another factor affecting replant and crop management decisions following the excessive rainfall events in June is the type Federal Crop Insurance policy and level of insurance coverage that a farm operator is carrying for 2018. Producers with a “replant clause” on their crop insurance coverage could be eligible for some compensation for replanting following crop losses from heavy rains, hail, or other natural causes. To qualify for replant compensation, farmers must have a loss area of at least 20 acres, or 20 percent of the total acres in an insured farm unit, whichever is less. With “enterprise units”, smaller areas of fields may be grouped together to reach that threshold level. The crop insurance replant provision can only be exercised once in a given year on the same crop acres. Some farm operators may have already used the replant option following poor emergence in late May or early June, and thus could not use the replant provision again, following the recent excessive rainfall.

Crop producers will need to decide if replanting corn or soybeans in early July is a viable option. Corn could likely only be used as livestock feed, and soybeans planted after July 1 in Southern Minnesota only have a yield potential of about 20-25 bushels per acre. The 2018 crop insurance base prices were $3.96 per bushel for corn and $10.19 per bushel for soybeans. Today’s prices for December corn futures are near $3.70 per bushel, and near $8.90 per bushel for November soybean futures. At those price levels, with an 80 percent crop insurance policy for corn, a producer with a 200 bushel per acre APH corn yield would start collecting crop insurance indemnity payments at a final corn yield of approximately 170 bushels per acre. A producer with an 80 percent policy and a 55 bushel per acre APH soybean yield would have payments begin below a final yield of about 50 bushels per acre.

With crop insurance every situation is different, depending on the type of insurance policy and the level of insurance coverage. Producers need to closely analyze the yield potential of the remaining crop, as well as the current status of their crop insurance benefits, before finalizing crop replant decisions after July 1, or when deciding to spend considerable dollars for more crop inputs on a poor crop. Farm operators should consult with their crop insurance agent and agronomist or crop consultant before finalizing additional crop input and replant decisions.



Note — For additional information contact Kent Thiesse, Farm Management Analyst and Senior

Vice President, MinnStar Bank, Lake Crystal, MN. (Phone — (507) 381-7960);

E-mail — kent.thiesse@minnstarbank.com)


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