Soil is a natural body consisting of layers (soil horizons) of mineral
A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...

 constituents of variable thicknesses, which differ from the parent materials in their morphological
Geomorphology is the scientific study of landforms and the processes that shape them...

, physical, chemical, and mineralogical characteristics. Strictly speaking, soil is the depth of regolith that influence and have been influenced by plant roots.

Soil is composed of particles of broken rock
Rock (geology)
In geology, rock or stone is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic...

 that have been altered by chemical and mechanical processes that include weathering
Weathering is the breaking down of rocks, soils and minerals as well as artificial materials through contact with the Earth's atmosphere, biota and waters...

 and erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...


“Man has only a thin layer of soil between himself and starvation.” ~ Bard of Cincinnati

“We all should fall upon our knees and sing out praise for manganese.” ~ Richmond Bartlett

“I saw all the people hustling early in the morning to go into the factories and the stores and the office buildings, to do their job, to get their check. But ultimately it's not office buildings or jobs that give us our checks. It's the soil. The soil is what gives us the real income that supports us all” ~ Ed Begley, Jr.

“History is largely a record of human struggle to wrest the land from nature, because man relies for sustenance on the products of the soil. So direct is the relationship between soil erosion, the productivity of the land, and the prosperity of people, that the history of mankind, to a considerable degree at least, may be interpreted in terms of the soil and what has happened to it as the result of human use.” ~ Hugh H. Bennett and W.C. Lowdermilk, circa 1930s

“... if this is to be a permanent nation we must save this most indispensable of all our God-given assets -- the soil, from which comes our food and raiment. If we fail in this, remember that much sooner than we have expected this will be a nation of subsoil farmers.” ~ Hugh H. Bennett (1933)

“Soil erosion is as old as agriculture. It began when the first heavy rain struck the first furrow turned by a crude implement of tillage in the hands or prehistoric man. It has been going on ever since, wherever man's culture of the earth has bared the soil to rain and wind.” ~ Hugh H. Bennett and W.C. Lowdermilk, circa 1930s

“The plain truth is that Americans, as a people, have never learned to love the land and to regard it as an enduring resource.” ~ Soil Conservation by Hugh H. Bennett

“The soil is the great connector of our lives, the source and destination of all.” ~ The Unsettling of America (1977) by Wendell Berry

“There be three things which make a nation great and prosperous: a fertile soil, busy workshops, easy conveyance for men and goods from place to place” ~ Francis Bacon Sr.

“The richest soil, if cultivated, produces the rankest weeds” ~ Plutarch