Planting Nearly Complete
Category: Crop Conditions
Across Southern Minnesota and Northern Iowa, nearly all the intended corn is planted, and over 90 percent of the soybeans were planted as of May 18. Most of the corn and many of the soybeans that are planted in this region have emerged, and stands look fairly good. However, strong winds on May 17 and 18 in Southern and Western Minnesota caused considerable blowing dirt, which did cause some crop damage to newly emerged corn and soybeans. In addition, the intense thunderstorms during the first week of May caused considerable soil crusting in some areas, which has lead to emergence problems for corn and soybeans that were just planted prior to the heavy rainfall events. In the most severe locations, portions of fields were replanted due to the soil crusting, as well as due to drown-out damage in low areas of fields resulting from excess rainfall.
At the University of Minnesota Southern Research and Outreach Center at Waseca, the average air temperature in May (as of May 18) was 60.3 degrees F, compared to a 30-year average May temperature of 58.4 degrees F. As of May 18, the accumulation of growing degree units (GDU’s) in 2012 at Waseca was 212 GDU’s, which is 28 percent above the 30-year average of 166 GDU’s accumulated by May 18. Some corn was planted in mid-April, and was able to take advantage of some accumulated GDU’s in late April as well, resulting in corn growth that is well ahead of normal.
The total precipitation recorded in May at Waseca, was 2.87 inches, as of May 18, with nearly all of the measurable precipitation being recorded during the first six days of May. Portions of South Central and Southwest Minnesota received 4-6 inches of rainfall during intense thunderstorms from May 1-6, which lead to the drown-out damage and soil crusting problems in some fields. The average precipitation at Waseca for the entire month of May is 3.96 inches. Stored soil moisture in many areas has made a nice recovery from the depleted conditions that existed earlier this Spring.
Most producers will be applying post-emergence herbicides for weed control in corn and soybeans during the next couple of weeks. They are hoping for some rain-free days, with a minimal amount of wind, to provide for good spraying conditions. With the high amount of acres planted to “Round-up Ready” corn hybrids and soybean varieties, or similar crop genetics, a majority of the weed control in corn and soybean production is accomplished through the use of post-emergence herbicides that are applied after the crop and the weeds are emerged and growing. By comparison, 10-15 years ago, post-emergence herbicides for weed control were secondary to the use of soil-applied pre-plant and pre-emergence herbicides to control weeds before they emerged. In addition to giving crop producers better options and more flexibility for weed control, the move toward a higher percentage of post-emergence herbicides has also been more environmentally friendly. The post-emergence herbicides are generally safer to use and are much less likely to run-off into lakes, rivers, streams, or tile lines, as compared to many of older soil applied chemicals.