Across the planet, moderate to extreme soil erosion has degraded 3 billion acres of agricultural land since 1945 – an area the size of China and India combined. This estimate, by the United nations, is that 38% of global cropland has been seriously degraded since WW II. Each year, farms around the world lose 75 billion metric tons of soil, eroded to the oceans. This much land could feed billions of people. We are running out of dirt we cannot afford to lose.