A while back, I observed some fields with high corn rootworm beetle pressure. I'm sure we're all familiar with the damage they can do in their larval form chewing up roots. This year, I noticed an unusual amount of pressure from the beetle form.
The first symptom is a scratching appearance on the corn leaves. As silks and tassels form, one notices the beetles begin to move and feed on these delicious, vulnerable organs. Tassel damage is bad, but silk clipping is where they really cause damage. A silk that is clipped early is a kernel that does not pollinate. I will follow this feeding through the season to see how much damage occurs. Older thresholds are not very reliable with today's grain prices.
