OK, maybe my recent trip to Nebraska and the gleanings I'm writing about from that trip don't add up to a classic like "From Russia with Love.' But they might prove insightful, especially if you're still trying to gauge how accurate USDA crop estimates are, and use what information you can find to do some crop pricing.
Traveling from Indiana to Nebraska, and walking a few fields, doesn't deliver the image of a huge corn crop. What is more evident instead are areas of paler-than-normal corn, sometimes closer to yellow, in field after field. Are there always yell0ow, nitrogen deficient spots in any season? Yes, probably- and true, we're looking for them this year because everyone suspects that due to the wet spring, enough N may have been lost to reduce the amount available to crops, and show up in lower final yield.
Several ag economists and marketing experts still believe that could happen. The October report could reveal a truer picture of corn yield in the field than the September report did, and the final proof this year will be in the final report for the '08 season issued by USDA in January '09, one source says.
From Franklin to Grand Island Nebraska, and at nearly all parts in between, if you look closely, leaves on plants in otherwise still-green fields are turning yellow form the tip, and growing yellow, then brown as tissues dies, from the tip back down the midrib. That's a classic sign on N deficiency," says Dave Nanda, Bird Hybrids, LLC, Tiffin, Ohio, and a Farm Progress Corn Illustrated project crops consultant.
That's not how plants are supposed to senesce at the end of the season, Nanda says. Instead, it's a clear sign that plants are running out of nitrogen late in the season. Since many of these areas took 20 inches or more of water in less than two months, it's not surprising that leaching and other forms of N loss have combined to leave less within the root zone where plants can access it than what they need to produce top yields. Kernels are there, but may not fill out as completely as they might have should the plants have had enough N. And if plants run short of nitrogen and other nutrients, they will cannibalize the stalks, leaving them more vulnerable to stalk rot. Nanda believes lodging will be a key issue this fall, and urges farmers to consider beginning harvest around 30% moisture, even though it means doing considerable drying- something they haven't had to do for several seasons to any extent.
What really troubles Nanda is that many of the classic symptoms in many fields he's been in are above the ear leaf. When leaves above the ear leaf show significant signs of N deficiency, or of any other stress, it's a tell-tale sign that the plant is probably in enough trouble due to lack of the nutrient, or due to a disease, whichever the case may be, that yield loss is likely.
If these observations are accurate, USDA yields may yet fall as the season progresses. In 1993, a similar season in many respects, yield estimates did fall as the season progressed, with a considerable drop coming in the final yield estimate of the year.