How much corn do you have planted? How about your neighbors? Are you leading the pack or trying to keep up with the neighbors? There is a good possibility that over half of the counties in the Cornbelt have corn in the ground, thanks to the unusually warm end to winter and finally, warm start to spring. And if you have rented additional ground for 2012, you might already be feeling behind schedule. But with 10 days still on the March calendar, is it too early to really feel pressed to put seed in the ground?

The central part of the Cornbelt has benefited from warm weather, thanks to the jet stream that has resulted from the transition from La Niña to El Niño. In the weather, nothing is ever normal or average, but that description is reached as a passing fancy. And while 2012 temperatures will certainly raise the average, another year will bring something on the other end of the spectrum. But for now, many Cornbelt farmers have been working fields for several weeks and many have also been planting mid-March corn. Why? Because they can.

University of Illinois crop production specialist Emerson Nafziger says with a continuation of the warm temperatures, the crop would be expected to get off to a fast start. Calculating Growing Degree Days, Nafziger says about 15 to 18 are being collected every day, and that means it would take about a week to accumulate enough to provide the 115 needed for germination. At this time of year, there would typically not be any collected, or only a handful per week at the most. And in most other years, overnight temperatures in March and early April would provide sufficient amount of frost to stun young corn plants back to ground level.

Based on soil temperatures being reported around the Cornbelt, (IL for example) many soil temperatures are above typical corn planting, and the trend has been for increasing temperatures. Nafziger says, “If it stays warm and doesn’t get wet, we normally would expect planting to get going in late March, with April 1 being the “go” date for many in the southern two-thirds of Illinois.” (Equate that latitude to your state.) 

Nafziger says his many years of research have never planted corn in mid-March. However, he says there is plenty of research on corn planted in late March and compared to early April for yield advantages. “Of 12 trials conducted over the past three years, corn planted in late April has yielded more than corn planted in late March or early April nine times, and the earlier planting has yielded more three times. The average advantage from planting later was about 4 bushels per acre.”

Because planting date responses are unpredictable, Nafziger says there is no certainty that corn planted in late March will yield any more or less than corn planted in late April. But he says consider the soil moisture and the growing degree days. With more time for root development, early corn may be able to take up more water than later planted corn. But for Growing Degree Days, the typical amount is minimal in March and April and there may not be enough heat units to help the corn plants, and “early planting may not mean early pollination, maturity, and harvest.”

Nafziger expresses concern about a return to low and even sub-freezing temperatures, which would not only trump the early planting opportunity, but farmers may find replacement seed difficult to obtain either the hybrid numbers they want or quantity they want. Crop insurance for much of the central Cornbelt has an early April date for planting with coverage for replacement seed. He says, “Unless temperatures remain far above normal over the next month or more, the risk of planting now may well outweigh the likely return.” 

Summary:
Corn is being planted across the Cornbelt, with the help of warm temperatures that have warmed up the soil beyond normal levels for this time of year. Although there is little difference in yield between corn planted in late March or late April, the is the added threat of significant crop damage with a freeze in the next several weeks before typical warm up. 

Source: FarmGate blog