May 26, 2010
Crop Condition Ratings Need to be Viewed with Caution
Author: Michael Cordonnier/Soybean & Corn Advisor, Inc.
The early corn condition ratings indicated that 71% of the U.S. corn crop is rated as good to excellent. With warmer temperatures in the Corn Belt this week, the condition rating are expected to improve next week as more corn emerges and starts to turn a darker shade of green.
Every year it's good to remember just how these condition ratings are compiled. They are the result of thousands of observers sending in their ratings about how the crop looks from afar, or what is commonly referred to as a "windshield surveys". These types of ratings are OK during the first half of the growing season, but once the crops enter into their reproductive cycles, the value of these ratings diminish.
Later in the summer you really need to get in the fields and physically look at the crops in order to judge what is happening to the crops. For corn, you need to peel back the husks to see if pollination was successful. To get a feel for the yield potential, you need to count the number of ears and look at the number of rows per ear and the length of the ear. For soybeans, you need to see the pod set, how many seeds per pod, and the potential size of the soybean seeds. All of this can only be seen by going into the field. Later in the growing season just looking at the crop from the highway does not give a complete picture of what might be happening.
These condition ratings should be viewed as a judge of the outward health of the crop and not so much as a way to judge the eventual yield prospects of the crop. The biggest value of these ratings is that they afford a way to compare the current crops with crops in the past.