By Angie Peltier
State and Region. According to the USDA's National Agricultural Statistics Service corn planting and emergence and soybean planting in Illinois have progressed faster than the running 5-year average (2011-2015, Figure). Similar to in 2015, the nine counties that make up the western Illinois crop reporting district lead the state in both corn and soybean planting, with 94 percent of the corn and 33 percent of the soybean acres planted as of May 8 (Figure).
Northwestern Illinois Agricultural Research and Demonstration Center (NWIARDC). Weather and soil conditions have been a little less conducive to planting at many points throughout this growing season at the NWIARDC. According to the Illinois State Water Survey's Water and Atmospheric Monitoring (WARM) program, between April 18 and May 10 there were 9 days in which more than 0.3 inches of rain fell, for a total of 5.86 inches (Figure).
Yellow corn. In a corn planting date trial at the NWIARDC, corn was planted on April 5 and April 15 and May 5. Corn planted on April 5 has emerged with two leaf collars visible, although the cool temperatures and wet soils have kept the plants a yellow-greenish color (Figure).
In an article written in May 2010, Purdue University corn agronomist Dr. Bob Nielsen says that corn plants at this stage of growth, and up until about the third leaf-collar stage, rely primarily upon nutrients supplied by the seed until they transition to relying upon nutrients reached by their nodal roots.
He states that,
"During this important transition from dependence on kernel reserves to dependence on the nodal root system, corn seedlings are easily sidetracked when growing conditions are not adequate for maximum photosynthesis and rapid development of the nodal root system. Consequently, the appearance of corn seedlings during these early leaf stages can be downright ugly during extended periods of cloudy weather."
Concluding that
"The best remedy for most fields of yellow-green corn seedlings suffering from the effect of "crappy growing conditions is the return of ample sunshine and warmth."
Unfortunately for this and other corn in the area, the short-term weather forecasts another 1/2 inch of rain and cool temperatures into the weekend, with lows in the low 40s. But warmer temperatures and drier soils are bound to arrive sometime soon.