Crop Conditions Variable With Excessive Rainfall In Some Areas

The old saying “rain makes grain” may hold true in many instances; however, excessive precipitation amounts again this year early in the growing season has caused extensive crop loss in some areas of the Upper Midwest. Portions of West Central and Southern Minnesota have been impacted by severe storms and excessive rainfall amounts in recent weeks. This has caused considerable drown-out areas in some fields, as well as crop damage to the remaining crop in many fields. In addition, severe storms have caused considerable hail damage to crops in some locations in the Upper Midwest, as well as tornadoes and strong winds that have damaged grain bins and farm buildings.
 
Portions of West Central Minnesota have received 200 percent or more of their normal rainfall amount for the month of June during a 10-day period in mid-June. Many locations in the Upper Midwest have had rainfall amounts during the month of June that are well above normal. Some locations in West Central Minnesota received 6-10 inches of rain or more during a 3-day period in mid-June, and have received additional rainfall since that time. There was also a large area of eastern South Central Minnesota that received excessive rainfall amounts during that period. Soils in the impacted areas of the region are totally saturated and drainage systems are at capacity, so any amount of excessive rainfall can quite rapidly result in considerable standing water in crop fields. In affected areas, the primary crop loss has been to existing crops that had already been planted in 2025.
 
The heavy rainfall in 2025 have been more localized in nature than the large major rainfall events in Southern Minnesota and Northern Iowa in 2024 that caused major flooding and crop loss. As of June 23, the University of Minnesota Southern Research and Outreach Center at Waseca had received just over 4 inches of rainfall during the month of June, which compares to a normal average June rainfall of 5.32 inches. For the year, total precipitation at the Waseca site is just over 16 inches, or about 1.8 inches below normal. By comparison, the research center at Waseca received 12.45 inches of rainfall during June in 2024, and received a total of over 19 inches of precipitation in May and June last year. Even though the June rainfall at the Waseca research facility is slightly below normal, just a few miles away in extreme Southern Minnesota, some areas have received 8-10 inches of rainfall or more during June.
 
In addition to the crop loss from the excess precipitation, another major concern that is developing as a result of the frequent heavy June rainfall events is the loss or lack of available nitrogen for the growing corn. Much of the nitrogen fertilizer for the 2025 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. As a result of these situations, there may be a need for 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 allowable applications of dicamba herbicide in soybeans in many areas, 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 2025 corn crop, as well as for late season post-emergence herbicide options for this year’s crop.
 
 
The weekly U.S. Drought Monitor that was released on June 19 shows a growing area of drought conditions in much of Nebraska and South Dakota, as well as in parts of western and southern Iowa. Portions of southwest Minnesota were also listed with some level of drought concern; however the overall drought footprint in Minnesota has diminished considerably in the past month or so. As of June 15, the U of M Southwest Research and Outreach Center at Lamberton, Minnesota had recorded only 3.44 inches of precipitation from May 1 through June 15, which was about 2 inches below the normal precipitation for the early portion of the growing season. The stored soil moisture was at 6 inches in the top 5 feet of the soil profile at the Lamberton site, which is just slightly lower than the long term average for mid-June. A year ago, the stored soil moisture level in June at Lamberton was at the maximum capacity of 9.1 inches. At this point, the rainfall at Lamberton has been adequate and very timely for good crop growth and development.
 
Warmer weather during the last half of June has resulted in rapid crop growth and development in most portions of the Corn Belt. As of June 23, the accumulated growing degree units (GDU’s) at the Waseca Research Center since May 1 totaled 774 GDU’s, which is slightly ahead of normal and is very similar to the GDU figures in late June in 2024. In areas that have avoided the heavy rainfall events and crop loss in June, the adequate moisture and warmer temperatures have resulted in favorable growing conditions for corn and soybeans in most areas of the Midwest.
 
The weekly USDA Crop Condition Report on June 16 listed 72 percent of the U.S. corn crop and 68 percent of the U.S. soybean crop as “good to excellent”. The crop rating has remained fairly steady in recent weeks; however, there is some concern due to developing dryness in portions of the Western Corn Belt and the Central Plains States. The “good-to-excellent” crop ratings for Iowa were at 84 percent for corn and 80 percent for soybeans, while Minnesota was at 75 percent for corn and 74 percent for soybeans. The June 16 “good-to-excellent” crop ratings for both corn and soybeans were also near the U.S. average in Illinois, Nebraska, and Missouri. About the only major corn and soybean producing States that are slightly lower than the national average “good-to-excellent” rating for corn and soybeans were South Dakota, Indiana, and Ohio. Only 5 percent of the corn and soybeans in the U.S. were rated as “poor” in the June 16 report.
 
Crop Insurance Considerations
Farmers in areas that received excessive rainfall during June have been contemplating replant decisions. These decisions may vary from farm-to-farm depending on the type of Federal Crop Insurance policy and the level of insurance coverage that a farm operator is carrying for 2025. 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.
 
Producers need to report prevented planted and replant acres need their crop insurance agent. The insurance agents can also be a good resource regarding final planting dates, prevented planting options, and replant considerations. Every producer’s situation is different regarding late and prevented planting options. As a result, the best option will vary considerably from farm-to-farm, depending on differences in yield potential and insurance coverage. In addition to their crop insurance agent, farmers should consult with their agronomist, farm management advisor, and ag lender regarding the best options for replant decisions. The choice that is made could result in a difference of thousands of dollars by year-end, depending on the resulting crop production and crop insurance coverage.
For additional information contact Kent Thiesse, Farm Management Analyst, Green Solutions Group
Phone - (507) 381-7960; E-mail - [email protected]