We lose about 1.7 billion tons of soil per year from just our cropland. That is a lot, but it's better than it used to be. Over the past 25 years we have reduced soil erosion by over 40%, mainly by conservation practices such as conservation tillage, terracing, cover crops, and grass waterways. It can take roughly 500 to 1000 years to form one inch of soil, depending on the climate and the material from which soil forms.