The best soil is from regenerative farms and ranches. We bought next to pocket of these farms and the soil health is rich and the air quality is pure. Stay far away from monoculture factory farms.
As far as where is the best soil, anyone can create rich top soil through composting, no tilling, cover crops, animal grazing etc.
America only has 40 years left of top soil because of the obvious reasons. 1% of US farmland is organic the rest is being molested by large food corps.
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