The Crop Watch field is about 50% harvested. There are no yield reports yet – we will wait for the report from the whole field. The story here is that the farmer stopped harvesting corn and switched to harvesting soybeans. For him, it's the right move.

Crop Watch 9/28: Stalk rot shows up in more fields as season progresses

Why? The corn in that field is still standing well. Despite pressure from disease, held in check somewhat by a fungicide application but still quite visible, the corn is still upright with some green tissue left.

Crop Watch 2015: Crop watch field is half harvested, farmer switches to soybeans.

On the other hand, due to a long dry spell, soybeans are drying down and sometimes moisture is below 13%, the point at which you don't receive dock at the elevator.

Grain specialists say that once soybeans drop below 11%, you lose weight because elevators don't correct back to 13%. So you lose bushels and revenue. Shattering loss also tends to increase so you leave more soybeans on the ground.

What if your corn isn't standing as well as this field? What if half or more of the stalks fail the push or pinch test, meaning a good wind would knock them over? Then the decision might become more interesting.

One farmer's answer who has a few corn fields like that is to continue harvesting soybeans until they get to later maturity beans that aren't pushing the low moisture side. Then he intends to jump in and harvest corn, starting with all the fields planted to the hybrid that is showing signs of weak stalks.

Crop Watch 9/25: Here's how bad corn plants want to 'make babies'

Should it rain, he will also be ready to switch to corn. His area has turned so dry that it would take major rain to prevent him from harvesting corn soon afterwards.

Soybeans or corn: It's the time of year to balance loss of soybean dry matter if beans get too dry vs. fields where corn stalks are deteriorating.

The farmer says he wouldn't have known that the stalks in that field were deteriorating if he hadn't gone into the field to see if the cover crops he interseeded by airplane earlier were growing. Now he intends to check all of his fields and line up an order of harvest for both corn and soybeans.