Check you ears!

No pun intended actually, we really do need to get into the cornfields and check your ears prior to harvest. I received a call today from a local crop scout who has been seeing and hearing of 'beer can' ears around the county. This is a phenomenon where the bottom few rows of the ear are properly filled while the top of the cob is barren. This obviously can cost a lot of yield.

It is believed that this phenomenon is usually due to a cold snap when the corn plant is forming the ear (V5-V8). This always occurs in this manner since corn will always develop kernels from the bottom of the ear to the top. So what fields are at risk? Well typically it appears that it takes lower 40s to stress the corn so I dove into the this years temperature records to try to pin this down.

It appears the May 14th and 19th are likely the main dates when damage likely occurred. Hagerstown Airport reported a low of 41 degrees for both days. If we look at the fact that it typically takes 4 weeks to reach V8 (where ear development is thought to be complete) and V5 is normally about 3 weeks after planting we can assume the highest risk corn for this abnormality was planted between April 14th and April 28th (due to two dates with low temps). Obviously any fields around this period should be checked. Overall, you may want to check all your early plantings.

The main issue with this abnormality would be decreased yield when shelling the corn. If you have the ability to chop this corn for silage and shell another field it may be advantageous. Of course you will take a hit on energy in your silage as well, however it may be a better option.