We wanted to take a little time to tell everyone what we have been seeing in the field recently, as well as what we will be keeping our eyes on going forward as the 2023 corn crop comes to a finish.
The Conditions that Got Us Here
As of today, we are seeing the majority of fields holding up fairly well in plant health, but with that being said, there are some changes taking place after the last bout of heat that we had last week. But to start, let’s take a quick look at the conditions that have gotten us to where we are today.
We had 3 planting windows this year in which the majority of corn was planted. April 12-19 being the first window, the May 3-6 time frame was the window when the majority of corn was planted with the remainder being planted in the May 17-20 time frame. The May 3-6 planted corn was immediately followed by a hard beating rain the night of May 6th into the morning of May 7th which resulted in a lot of uneven emergence. That uneven emergence is a variable that has played a role in some of the results we are seeing now, primarily smaller plants and “off type” ears that are ½ to ¾ in size vs. full ears which in the end effects our final bushels per/1000. Throughout the months of May and June, we continued to be very dry until the derecho came in in late June. Some of the hardest hit areas from the derecho sustained some heavy damage, but the majority of the corn crop saw some small percentage of green snap and some root lodging. Root lodging at that stage sometimes will result in some smaller plants and ears. Early July brought some needed moisture, but as the month progressed, we really got dry again teetering on the edge of losing a lot of bushels. We had a few days of really high temperatures towards the end of July accompanied by some higher than normal nighttime temps. This is most likely the timeframe that hurt us most for ears tipping back. A good round of rainfall at the beginning of August really put things back on track and enabled plants to stay healthy and takes us where we are today.
What have we been seeing in the fields?
Let’s dive in. Close to two weeks ago we started noticing some “ghost” plants show up in the April planted corn. These plants are losing their color from the top down and look like they are dying prematurely. These plants were being affected by top die back caused by anthracnose, and/or crown rot in the stalk. We are now seeing the same thing happen to the corn planted in the first May timeframe. The cause of this is multi-faceted. The most affected plants are those that emerged late and also in highly compacted areas of the field (mostly field edges). We believe the multiple rounds of stress from dry weather and heat also played a big role. Normally, this condition will cause those plants to not be able to fill out to their full grain weight. We have added some pictures below of what these plants look like both with the dying tops, as well as the anthracnose in the stalk. To date, we have seen fields with very little of this top die back condition, as well as fields with as much as 40 percent in some of the earliest planted corn. Foliar disease including tar spot is at very low levels overall, and we don’t expect that to accelerate and play a role in the crops’ finish. Nitrogen deficiency has been somewhat non-existent throughout this season, and nitrogen utilization and mineralization has been excellent which will help us in a positive direction to finish. During the driest part of June, potassium deficiency was very common and got somewhat corrected when we received more moisture. Overall we are seeing better kernel retention than a year ago but more “off type” ears and plants. The early May corn is showing a moisture line approximately 1/3 of the way down so there is a fair amount of weight yet to be determined. As we look at conditions to date, the corn crop looks solid with the biggest limiting factor being uneven emerged plants.
Here are a couple links discussing the different stalk rots that affect corn, as well as crown rot.