What is the difference between topsoil and subsoil?
At undisturbed locations, topsoil is the soil on top of the ground. It usually contains more nutrients, organic matter and microorganisms than subsoil, and will better support plant growth. Subsoil is below the topsoil and has fewer nutrients, organic matter and microorganisms, which can make growing plants from seed quite challenging. The purpose of adding topsoil is to increase the water and nutrient holding capacity of an existing soil. Why are pore spaces important? Pore spaces are cavities in the soil that allow water to pass through when it rains, and serve as a channel for oxygen to reach the roots. An ideal soil is 50% pore spaces! Construction vehicle traffic, bulldozing a final grade, and dogs running in the same path all compact a soil, which reduces the size and number of pore spaces. Compaction often increases when tillage is performed when the soil is wet rather than dry. An impatient homeowner demanding that a landscaper rake and install a lawn when the soil is too wet c
