Thousands of years of poor farming and ranching practices and, especially, modern industrial agriculturehave led to the loss of up to 80 percent of carbon from the worlds soils. That carbon is now floating in the atmosphere, and even if we stopped using fossil fuels today, it would continue warming the planet. In The Soil Will Save Us, journalist and bestselling author Kristin Ohlson makes an elegantly argued, passionate case for "our great green...