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.

• Making taxes pull double duty

  • Detrimental practices including topsoil depletion, non-renewable logging, and most mineral and metal extraction processes (including the mining of bauxite, chromium, coal, gold and silver) would provide additional taxation targets.

• Farm Policy of the 20th Century

  • Persistent winds during an extended drought blew away topsoil from vast tracts of once-productive farmland.

• 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.

• Dust Bowl Migrants

  • Deep plowing of the virgin topsoil of the Great Plains had displaced the natural deep-rooted grasses that normally kept the soil in place and trapped moisture even during periods of drought and high winds.

• The Human Toll

  • Deep plowing of the virgin topsoil of the Great Plains displaced the natural deep-rooted grasses that normally kept the soil in place and trapped moisture even during periods of drought and high winds.