Mark Lawson, farmer and Syngenta agronomist in Danville, Ind., says trying to make sense of yield results without ever seeing the field before harvest is like an autopsy – it's hard to figure out why a patient died when you never saw the patient when he or she was alive.
That may be the biggest lesson to take from 2013, he says. You can't explain why corn planted June 15 yielded 251 bushels per acre, unless you know something about what went on during the season. In this case you need to know that tissue samples were routinely taken, and that extra nutrients were added as needed. You also need to know the farmer added nutrients through irrigation with a center pivot rig, even when the crop didn't need water. His neighbors thought he was nuts. He laughed all the way to the storage bin with a huge crop this fall.
You also can't explain why every ear in one field had an inch of more of blank tip unless you were there during the season. The field still made over 200 bushels per acre. You needed to be there to see the nitrogen deficiency in early August, combined with very dry weather. The plants decided to make the kernels they had, and abort the rest. Since you were in the field right after pollinating, you know that the kernels were fertilized and started to form, and then aborted.
You also need to ask questions. In this case you would discover that the farmer had trouble getting the nitrogen applicator set in that field, and wound up applying at least 15 pounds per acre less N than he intended. Since he was cutting the rate close anyway, the 15 pound shortage was a big deal when a huge crop tried to form and kept calling for more nitrogen than the soil could supply.
You don't know any of that if you didn't follow the field during the season. The real message from 2013 is that you need to follow the crop all season long to explain why yield results turn out as they do in the end.