Danny Greene looked carefully through the Crop Watch '14 field, looking for any signs of diseases or problems. Greene operates Greene Crop Consulting in Franklin.
He kept looking at what looked like small scratch marks on a leaf. He moved down a few plants and found the same thing. It didn't look like a big deal to me.
"It's not a big deal," he said, sensing what I was thinking. "But you don't see it every day. It's slight feeding caused by leaf miners, a relatively unknown insect.
"Is it one we should worry about?" I asked.
"No, not at all," he says. "You'll see about this much damage and that will be the end of it. It's just nice to recognize what the cause likely is so you know what's going on in the cornfield, and so you know if something is a problem or not."
We didn't run across any rootworm beetles or Japanese beetles. Since the corn was still silking and fertilizing, then it might have been a different story. However, most of the ears we checked were about 80% to 90% pollinated, with only the tips to go. Once corn reaches that stage, even if beetles are clipping silks it may not be worth treatment. The silks need to be clipped to within a half inch of the ear tip to raise concerns, agronomists say.
Greene gets more concerned if he finds gray leaf spot lesions or northern corn leaf blight lesions at this stage of the game. He's especially concerned if the finds them on the ear leaf or higher. The corn he checked in this field, however, was relatively clean. He found a few lesions of each disease, but not nearly enough to justify spraying if you were going to base spraying decisions solely on what you were seeing in the field.