AskDefine | Define topsoil

Dictionary Definition

topsoil n : the layer of soil on the surface [syn: surface soil]

User Contributed Dictionary



  1. The most fertile soil, easiest to start new plants in.
    Little grew on the farm, after the floods from the hurricaine washed away the topsoil.

Extensive Definition

Top Soil is the upper, outermost layer of soil, usually the top 2 to 8 inches. 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. 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 improving 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. Without topsoil, little plant life is possible. It takes approximately 500 years for one inch of topsoil to be deposited, but there are 25 billion tons of topsoil lost each year.

External links
topsoil in German: Mutterboden
topsoil in Lithuanian: Juodžemis
topsoil in Swedish: Matjord
topsoil in Chinese: 表土

Synonyms, Antonyms and Related Words

Privacy Policy, About Us, Terms and Conditions, Contact Us
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2
Material from Wikipedia, Wiktionary, Dict
Valid HTML 4.01 Strict, Valid CSS Level 2.1