Corn yield results not from the number ... “Normal-diameter stalks with small or missing ears indicate a problem in the reproductive stage, such as disease, insects, aphids or green snap.

The top kill phase of anthracnose may occur at any point above the ear from 4 to 6 weeks after pollination, while the lower portions of the stalk remain green. The top kill phase is easily confused ...

So even if corn ear tips are not filled completely ... often on the side of the cob away from the stalk that gives sort of a zippering look on the ears. The zippering often extends most of ...