topsoil

Examples of topsoil in the following topics:

• Physical Properties of Soil

  • Topsoil, the top layer of soil, is usually two to three inches deep, but this depth can vary considerably.
  • For instance, river deltas, such as the Mississippi River delta, have deep layers of topsoil.
  • Topsoil is rich in organic material.

• The Importance of Seedless Vascular Plants

  • Ferns contribute to the environment by promoting the weathering of rock, accelerating the formation of topsoil, and slowing down erosion by spreading rhizomes in the soil.