Looking ahead to Thursday's USDA numbers
Depending on August weather, this year’s corn crop will probably range between 162-168 bushels per acre. Cooler and wetter than normal conditions would put the crop in the upper range of estimates, while a warmer and drier outlook would likely put production in the lower end of predictions.
This compares with the USDA’s current estimate of 163.5 bushels per acre, and private forecasts of 162-167 bushels per acre.
I am reluctant to put a number on soybean production because the soybean plant is still in the process of reproduction. The number of nodes per plant is still unknown (that is where the pods form), and the plant remains in an ongoing process of producing flowers and setting pods.
Ear Count & Size
Though the ear count is projected to increase about 275 ears per acre compared to last year, the number of kernels per ear is expected to fall about 2.9%, from 594 kernels per ear last summer to 577 kernels this year.
Surprisingly, for some reason, grain length and rows around the cob are below last year, thus limiting the number of kernels per ear (see graphs at top of next page and on page 6). These observations suggest the corn yield this year across the 4-state area is actually about 4 bushels per acre below last year.
Kernel size (i.e. kernel weight) appears to be well above average which should compensate for the reduced number of kernels. However, that assumes the weather cooperates.
Perhaps arguably, the most influential factor in determining kernel weights is August weather. August temperatures in particular appear to be the primary key as below average temperatures tend to support above average kernel weights, while above average readings have an opposite effect. A big plus for both the corn and soybean crops is the excellent moisture situation. The only areas that appear to be too dry were most of the state of Ohio and some isolated pockets in eastern Illinois.
Insect pressures appear to be below average, which is probably a function of Bt corn. Disease pressures on the whole are probably above average with significant challenges in central and southern Illinois. Parts of Illinois will likely have to endure another year of mold issues.
The highest corn yields were found in northern and central Iowa and northern Illinois. My last seven stops through northern Iowa, which covered about 150 miles, had an average yield of 198 bushels per acre.
In any given year the 4-state sample area usually provides a fairly good assessment of corn yields across the entire Corn Belt. Typically the projected 4-state yields can be used to make reasonable estimates in the states to the north and south of the 4-state area.