Good point bobrown14. Plus, as much as 10% of the carbon found in the Plains of US from 10,000 years+ of prairie fires. Rumor has it there's pretty good soil in the mid west!
+1 on that - didn't the native Americans burn parts of the prairie to promote healthier bison thru healthier grass for them to feed on? they lived in a symbiotic relationship with bison for thousands of years. White settlers moved in, killed off the Bison and the native Americans, planted corn, now GMO corn cause the soil cant grow corn every year without fertilizers, insecticides and all that craziness.