What is the importance of topsoil?
Topsoil is the uppermost layer of soil, usually the top 2 to 8 inches. It has the highest concentration of organic matter and microorganisms and is therfore the most fertile. It is where most of the Earth’s biological soil activity occurs. Plants generally concentrate their roots here, and obtain most of their nutrients and moisture from this layer. The actual depth of the topsoil layer can be measured as the depth from the surface to the first densely packed soil layer known as hardpan. As one of the layers of soil on the Earth’s surface, topsoil is sometimes referred to as the A horizon. This layer is formed from the deposition of eroded material as well as decaying organic matter. A variety of soil mixtures are sold commercially as topsoil, usually for use in gardens and lawns, or for ideal growing conditions in container gardens, by using potting soil, for example. A major environmental concern known as topsoil erosion, occurs when the topsoil layer is blown or washed away as happe
