What a difference last week made in the planting progress here in Central Illinois and across many areas of the corn belt. Much of the corn in my area has been planted with a slug of beans being put in the ground much of last week through this week. Unfortunately, there are still areas experiencing wet conditions. I talked to one guy out in Ohio that’s still experiencing wet conditions and it sounded like there was a strong possibility for him to take prevent plant on all his corn acres and if conditions don’t improve, beans might not be planted either. Driving around central Illinois, I would say the condition of the corn crop has improved as we’ve dried things out but there are plenty of fields that are still riding the struggle bus compared to what we normally would expect this time of year in central Illinois. Some corn that is V3 and earlier is trying to establish its nodal root system which might cause yellowing in some fields particularly ones that have been waterlogged and compacted. Soil microbes are also starting to ramp up as conditions dry out and are tying up some of the nitrogen, sulfur, and other nutrients in the soil in order to break down old crop residues. This will cause yellowing in both corn and soybeans and is often referred to as the carbon penalty. Any yellowing seen in corn early on is likely to limit top end yield potential particularly in hybrids that flex in girth. In soybeans, this yellowing will likely go away once the soybean starts to make its own nitrogen which is at the V4 stage and shouldn’t limit yield potential a whole lot. A good way to manage this carbon penalty is to apply some nitrogen either broadcast or with your planter along with some sulfur. I had one grower apply some liquid UAN with some thiosulfate out the back of his planter and he saw a pretty good response in the early growth of his corn.
Speaking of early growth, phosphate-based starter fertilizer’s such as our Crop Choice® 3-18-18-1 or 9-18-9-1 that have a high concentration of phosphorus, push energy production and ultimately growth in the plant. Even if corn was planted late this year, I still expect to see a positive yield response if you used a phosphate-based starter fertilizer such as our Crop Choice blends. The positive yield response could even be as much or more than is typically seen when starter fertilizer is applied earlier in the season. This is due to the accelerated growth that should lead to earlier pollination and a longer grain fill period. This in turn will give about a week more of grain fill leading to higher kernel weight which will be the key to high yields with late planted corn. Usually lack of starch accumulation in the kernels due to a shortened ear fill window is why corn doesn’t yield quite as well when it’s planted late.
I’m also seeing a lot of sulfur and zinc deficiencies throughout the area and a foliar feed of these nutrients with your post emerge herbicides might be warranted. Our Foliar Opp® contains both sulfur and zinc plus other micronutrients and our Max72-SRN® contains sulfur but can be blended with zinc and other micronutrients as needed. We’ve seen both products add 5-10 bushels in corn when combined with our Sugar E-Boost®. With cash corn at $4.50 here in central Illinois, it only takes 2 bushels of corn to pay for this application.
I’m also seeing good performance out of our Landoil® and Soil Boost spray adjuvants. Once again both adjuvants are proving to be safe on the crop with very little herbicide response being observed in fields that had a full label rate of herbicide applied to them.
I hope things are looking better on your operation as we progress through this tough growing season. If you have any questions you can call our office or contact myself or other Soil Service salesman in your area.
Crop response of running UAN with thiosulfate on the planter.
Crop response of using a phosphate based starter (3-18-18-1 on the left) gives a rapid growth response that accelerates corn growth by 1 week.
Corn yellowing due to the carbon penalty.
Sulfur deficiency on corn appears as yellow stripping between the veins. Zinc and other micronutrients such as manganese can look similar.
Landoil and Soil Boost Extreme did an outstanding job controlling weeds and provided excellent crop safety.