depending on climate and other factors which is a reasonable length of time for soil to form to bedrock to fertile soil?
Answers
Formation of Soil . Let's put it this way--If you placed a wheelbarrow full of golf ball sized limestone outside, dust and windblown plant material, water, even bird manure, would accumulate next to the rocks. Soon plants would be growing among the rocks, furthering erosion through root growth, and freeze/thaw cycles would break the rocks even further. The acidity of the rainwater would gradually dissolve the limestone into smaller and smaller particles. The rate of erosion might be noticeable in a year's time, but would be dependent on the climate of the area where the rocks are placed. In an arid climate the rate of erosion might be very slow. Speed it up by putting it in a wet climate. In a related note, the loess, or windblown dust accumulation rate in Illinois during the last glaciation period was, on average, roughly 1" for every thousand years, resulting in 20' or more (in places) of extremely fertile soils worked by today's farmers.