The government has been collecting dirt—lots of it.
Clumps came from the Texas Panhandle, a shady grove in West Virginia, a picked-over corn field in Kansas and thousands of other places in the lower 48.
A small army of researchers and university students scattered across the country for three years to scoop samples into plastic bags from nearly 5,000 places.
Though always underfoot and often overlooked, dirt actually has a lot to tell. Scientists say information gleaned from it could help farmers grow better vegetables, build a better understanding of climate change and even solve crimes.
David Smith launched the U.S. Geological Survey project in 2001 and said data about the dirt will feed research for a century, and he's sharing it with anyone who wants it.
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