"Why don't you come on down," Jay Bell calls from the bottom of the University of Minnesota's soil pit. "It's a little slippery."
Six feet later, Bell invites a visitor to savor some of the subterranean earth, inhale its aroma. "The soil is literally alive," he says, scraping off a tablespoon-sized sample of the black, musky topsoil. "Those microbes are what's breaking down the organic matter and releasing the nutrients out into the soil."
Bell, a soil science professor at the U, wants you to know this isn't just dirt. It holds great beauty -- "Isn't this gorgeous?" he says at one point. "For me, I have pictures of soil hanging on my wall because that's like artwork."
Art perhaps, but the science of soil can have far-reaching effects, including climate change.
When the earth is tilled, Bell says carbon is released. Estimates vary, but there's no doubt, he adds, that the less soil is disturbed the more carbon is held in -- and that's a good thing for the environment since carbon contributes to climate change.
Soil scientists, though, don't know how rising temperatures will affect the ecology of Minnesota's millions of acres of fertile top soil.
Bell, 56, grew up in Virginia. He first applied his Virginia Tech environmental science training in that state's coal fields where mountaintop mining is common.
Coal companies blast the tops off mountains to get at coal seams. Bell says he worked for mining companies that needed to comply with federal land reclamation regulations.
The explosions, he says, had created soil-sized particles that could eventually be reclaimed to a sufficient degree to support apple orchards and forage crops.
His family still owns a 400-year-old Virginia farm with 70 farmable acres and a soil type that's fun to say: sassafras sandy loam.
Minnesota holds nearly 1,000 soil types. That includes the state's official soil, a dark, rich, loamy soil called Lester, named for the southern Minnesota town Lester Prairie.
Bell laughs at the creative labels for other soil types."My favorite is Bullwinkle." Bullwinkle is wet, found in fens and peat bogs, where it stores huge amounts of carbon. Bell says well over half of Minnesota's nearly 80,000 square miles of land is tillable.
Bell has examined 17-million-year-old soil in Australia that was played out after a couple years of farming. Minnesota's soil is in its infancy, by comparison. It's roughly 10,000 years old, with hundreds of years of resiliency -- even if abused.
Soil is precious. Bell says one reason its erosion should be taken seriously is that it can take 500 years to make an inch of topsoil.
Lots of people took America's rich farmland for granted until the Dust Bowl of the 1930s, he says. The prolonged drought spawned mammoth dust storms. Fierce winds scoured millions of tons of topsoil from plowed, erodible farm fields including Minnesota.
That crisis brought big changes. After that environmental disaster, the old-style plowing that dug deeply into the soil died out, land conservation practices started growing.
Now, climate change is the wild card.
A rise in temperature worldwide might change rainfall amounts and patterns, the length of the growing season and the biology of the state's most productive farmland.
"The whole ecology of the system would begin to change in ways that we probably can't predict," he says, "That's one of the things that's a little unsettling to me."