Focus on Ag: Severe storms damage crops in some areas

Kent Thiesse
Farm Management Analyst and Vice President, MinnStar Bank

Just about the time it appears that crop conditions seem to be improving, Mother Nature throws a new twist into the situation, which appears to be the case in 2019. After a very wet Spring and late planting season in most of the Midwest, crop conditions had begun to improve in late June and early July in many areas. However, a series of severe storms in Minnesota and other Upper Midwest States in mid-July has caused some crop damage and raised further questions about the quality of the 2019 corn and soybean crop.

Many portions of Minnesota and the surrounding States have received nearly double the normal precipitation amount for the month of July during the first three weeks of the month. Some areas received 5-8 inches of rainfall, or more, during the week of July 14-20 alone. Very hot and humid weather across the Upper Midwest raised dew points to extremely high levels creating numerous thunderstorms with excessive rainfall amounts. This has resulted in some drown-out damage in corn and soybean fields, as well as continual saturated soil conditions that are not very conducive to good crop growing conditions. In addition, there have been some severe storms across the region that have featured hail and wind damage to crops, causing leaned-over or broken corn stalks in some locations.

One concern that has developed as a result of the excessive rainfall levels was the loss or lack of available nitrogen for the growing corn. Soil nitrogen losses increase substantially during heavy rainfall events, such as have occurred in 2019. Corn plants in saturated soils have a much shallower root system and are not able to access the nitrogen that is deeper in the soil profile. In some cases, farmers have side dressed some nitrogen fertilizer; however, others have not able to apply any supplemental nitrogen due to the continual wet field conditions. Producers should evaluate the condition of the corn crop before deciding to invest in supplemental nitrogen applications this late in the 2019 growing season.

Another issue with the continual rainfall events and saturated soil conditions has been making timely herbicide applications to control broadleaf weeds. Most weed control management systems today for corn and soybeans rely heavily on post-emergence weed control applications during the growing season, which can be quite challenging in a year such as this. The continued wet field conditions have also created issues for farm operators that are trying to plant cover crops on prevented planted acres.

One positive about the weather trend during the first half of July was the warmer than average daytime and nighttime temperatures, which has resulted in a rapid accumulation of growing degree units (GDU’s). The accumulation of GDU’s at the U of M Southern Minnesota Research Center totaled 1,181 GDU’s from May 1 through July 17, 2019, which is still about 4 percent behind the normal GDU accumulation for that date. This is a big improvement from early-June, when the GDU accumulation in Southern Minnesota was 20-25 percent behind normal. By comparison, a total of 1,478.5 GDU’s had been accumulated at Waseca by July 17 a year ago in 2018.

Most of the Corn Belt dealt with some very late planting dates in 2019, as well as some cool temperatures and poor growing conditions in late May and early June. The warmer than normal temperatures have helped some of the later planted crops catch-up a bit on crop growth, as well as enhancing the crop development of corn and soybeans that were planted on a more-timely basis. Some of the corn that was planted in the first half of May began to tassel and pollinate during the week of July 14-20, which is only a few days behind normal.

The U.S. and Minnesota crop ratings in the weekly USDA Crop Progress Reports have remained fairly steady in recent weeks. The July 15 weekly report indicated that 58 percent of the corn and 60 percent of the soybeans in Minnesota were rated good to excellent, with 10 percent of the corn and 7 percent of the soybeans were rated poor or very poor. By comparison, at this same time in 2018, 77 percent of the corn and 75 percent of the soybeans in Minnesota were rated good to excellent. Nationally, 58 percent of the corn and 54 percent of the soybeans were rated good to excellent as of July 15, with most States in the Eastern Corn Belt below 50 percent good to excellent for both crops. A year-ago in mid-July, USDA rated 72 percent of the corn and 69 percent of the soybeans in the nation were rated as good to excellent.

In the July 11th World Supply and Demand Report (WASDE), USDA projected the 2019 U.S. average corn yield at 166 bushels per acre, and the 2019 U.S soybean yield at 48.5 bushels per acre. Many analysts are questioning the current USDA yield estimates, based on the challenging growing conditions in many areas of U.S. this year. Most likely, where final 2019 U.S. crop yields end up will depend heavily on the weather conditions in the next two months, as we approach fall harvest.

Most analysts are also questioning USDA’s 2019 crop acreage total in the July WASDE report, which indicated 91.7 million planted acres of corn and 80 million planted acres of soybeans. There was only a reduction of 5.7 million planted acres of corn and soybeans in the U.S., as compared to the original intended planted acres in the March USDA acreage report. Grain marketing analysts are typically estimating 10-12 million prevented planted acres of corn and soybeans for 2019. We should get a better indication of 2019 planted crop acres in the U.S. following the completion of crop acreage reporting at local Farm Service Agency (FSA) offices on July 22; however, we may not know the final crop acreage numbers until the harvestable acres are totaled for 2019.