By late last week, soybean harvest had resumed in most areas of southern Minnesota and northern Iowa. The resumption of soybean harvest varied from the early part of the week until very late in the week, depending on the amount of rainfall received during the severe storms on Sept. 22 and 23 and the follow-up field conditions. A large portion of southern Minnesota received 6-12 in. of rainfall during the two-day storm, and field conditions in some areas remained too wet to resume soybean harvest until recent days. However, in other portions of the region, soybean harvest was back in full swing by mid-week last week, and a considerable amount of soybeans have been harvested.
Farm operators in most parts of southern Minnesota have to pick and choose fields or portions of fields that are dry enough to support soybean combining. In many instances, producers are forced to leave parts of fields that have saturated soil conditions, with the hope of coming back later to complete the soybean harvest. Nearly all soybeans are fully mature and ready to harvest. One challenge with the soybean harvest is the increased shatter loss during combining, as the soybeans dry down to 10-11% moisture or lower during the recent warm, sunny days. This could become especially serious in fields or where wet soil conditions are preventing timely soybean harvest.
The good news with the soybean harvest in most areas is that the yields are above average to excellent. Many yield monitor and weigh-wagon soybean yields of 50-60 bu./acre or higher have been reported across the region. Of course, one must remember that whole-field yields are determined by dividing total bushels harvested by the total acres in a field that were planted last spring. That means any drowned out areas of the field, or other acres that are not harvestable due to wet field conditions, need to be factored in to the final yield calculation. In some cases this will significantly lower the final whole-field yield. There were also numerous soybean fields damaged by hail and severe storms throughout the growing season, which will reduce soybean yields in some areas.
Corn harvest is restarting in most areas, as soon as soybean harvest is completed, or if field conditions are too wet for soybean harvest. Nearly all corn in the region reached black layer by early September, and began to dry down naturally in the field. Most corn has now reached 20-22% moisture in the field, and continues to dry down naturally.
Ideally, corn needs to be dried to about 15-16% moisture for safe storage in on-farm grain bins until next spring or summer. It is likely that producers may be able to harvest much of their corn in 2010 with a very limited amount of supplemental corn drying. By comparison, most of the corn in southern Minnesota was at 27-32% moisture in early October 2009, requiring a significant amount of supplemental drying. Many farm operators had corn drying costs of $40-500/acre in 2009, as compared to less than $20/acre likely in 2010. In addition, the 2009 corn crop was very low test weight, well below the standard corn test weight of 56 lbs./bu. Corn test weights for 2010 appear to be much improved, and should be very near the standard test weight.
Fall tillage has been a little slow to occur in many areas, due the extremely wet field conditions. The immediate concern is for hog producers hoping to apply liquid hog manure as a fertilizer source for the 2011 crop year. The hog manure needs to be injected into the soil to take full advantage of the crop nutrients. Hopefully, the continued warm, dry weather pattern will allow proper manure application, as well as fall anhydrous ammonia fertilizer applications, to occur in workable soil conditions.
Climate change, or unusual weather?
The past couple of years there has been a lot of discussion about global warming and worldwide climate change. Many scientists differ on whether the unusual weather that has been occurring in the U.S. and other parts of the world in recent years is from long-term unusual weather trends, or from world climate change, potentially caused by global warming. Due to the numerous complex scientific factors involved in this discussion, it may be decades before we know the true answer to the causes of the abnormal worldwide weather patterns that we have seen in recent years.
At the University of Minnesota Research and Outreach Center at Waseca, the two-day rainfall total from the severe storms on Sept. 22 and 23, measured at 8 a.m. on Sept. 23 and 24, was 7.63 in. This was the highest two-day rainfall total in the 96-year history of weather data at the Waseca research facility, breaking the previous record of 6.32 in. in late August 1962. Interestingly, three monthly precipitation records for the past 96 years, or 1,149 months, have been set at Waseca in the past 12 months: 7.05 in. in October 2009, 9.64 in. in June 2010 and 12.66 in. in September 2010. Four of the six highest 24-hour precipitation totals at Waseca in 96 years have occurred in the past six years, including the highest 24-hour total of 5.63 in., measured on Sept. 23, 2010. Interestingly, the 30-year average annual precipitation at Waseca was 27.55 in./year from 1921 to 1950, compared to 34.70 in./year from 1971 to 2000.
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 [email protected]