Top Soil

What is Top Soil ?

Top soil is the uppermost layer of soil, usually the top 15-20 cm. It has the highest concentration of organic matter and microorganisms, and is where most of the Earth's biological soil activity occurs. Plants generally concentrate their roots in, and obtain most of their nutrients from this layer. Topsoil can be measured as the depth from the surface to the first densely packed soil layer known as hardpan.