MADISON--In an ongoing bid to grow more corn, farmers in the U.S. Corn Belt are planting seeds much earlier today than they did 30 years ago, a new study has found.
Poring over three decades of agricultural records, Christopher Kucharik, an associate scientist at the University of Wisconsin-Madison, discovered that farmers in 12 U.S. states now put corn in the ground around two weeks earlier than they did during the late 1970s. His findings appear in the current issue of the Agronomy Journal.
Earlier plantings-which mean longer growing seasons--have likely contributed to the increasing corn yields of recent decades. But Kucharik, a terrestrial ecologist at the UW-Madison's Center for Sustainability and the Global Environment, warns the trend can only continue for so long.
"Earlier plantings really can't continue forever because ultimately, farmers will have to contend with wintertime conditions and frozen soils," says Kucharik. "Several decades from now we might see an unexpected drop in annual yield increases when this trend plateaus, which could then increase the threat to our food supply."
The Corn Belt is a major agricultural region of the U.S. Midwest, where corn is a dominant crop. Centered in Iowa and Illinois, the belt extends into Wisconsin, Michigan, Minnesota, South Dakota, Nebraska, Kansas, Missouri, Indiana, Ohio and Kentucky.
Kucharik had initially set out to explore the wider influence of climate change on agricultural yields. But as he began to work with census data maintained by the U.S. Department of Agriculture, he accidentally noticed that over the decades, farmers have been planting most of their corn crops earlier and earlier in the year.
At first, he speculated that the pattern was simply a result of earlier springtime temperatures brought on by global warming. But on probing the last 30 years of the climate record, Kucharik found little proof that warmer weather motivated the early plan
'"/>
Contact: Christopher Kucharik
kucharik@wisc.edu
608-263-1859
University of Wisconsin-Madison
4-Oct-2006