As I’m driving across Iowa last week my cell phone rings, it’s a DSM from Michigan wondering what is going on with the corn in his district, the tops are dying?

While we are talking I look out the window and guess what I see, that’s right tops of the corn are dying. A quick call to Tim Jordal (Illinois Agronomist) and he has been seeing the same thing in Illinois.
So what is causing this “Top Die Back”, three things may be the cause,

1. Stress caused by severe drought, not the case, enough of rain in most areas this year
2. European Corn Borer, again most likely not the case, with all the BT corn planted across the corn belt this is a long shot.
3. Anthracnose, as Dave Hoy (Iowa Agronomist) would say “Winner, winner, chicken dinner”.

With Anthracnose Stalk Rot black lesions should be visible on the outer stalk tissue behind the leaf sheaths, this disease will usually affect small areas of a field or be plant to plant and as I drive through the hills of western Iowa these small areas are very noticeable.

So as the corn matures of course the bottoms of the plant start to turn and with the Anthracnose the tops are also brown, this gives a very unusual look to our corn fields with the middle of the plant being the only green left.

Here are a few articles that talk about this topic:

• ISU Top Dieback
• Purdue Top Dieback
• Top Dieback

SOURCE: Mitch Ray, CCA, GLH Product Manager