Soils Information By: Becky McGuire

Soil A. outer layer of earth’s crust, renewable natural resource that supports life --takes 1000 years for 1 inch of soil to form

Soil Components A. Soil is made up of: 1. Minerals—45% 2. Water—25% (good soil) 3. Air—25% 4. organic matter—5%

Pores A. spaces between soil particles. B. Filled with air and/or water

Mineral Material began as rock, undergoes weathering to break down 1. Classified according to particle size a. sand: largest in size, large pores, water flows through easily, not as fertile, nutrients leach out b. silt: mid-sized, good water holding capacity, holds nutrients C. clay: smallest in size, holds water and nutrients, has poor water drainage and lacks air

Soil Texture a. proportions of the 3 particle sizes in a soil --Landscapers need to know soil texture: 1. time to plant 2. drainage 3. nutrient holding capacity 4. plant soil requirements 5. easier to work with

Organic Matter A. decayed plants and animals 1. leaves, roots, stems 2. dark in color 3. more productive because of increased fertility/nutrients sources: manure, mulch, peat moss

Water A. necessary for good soil --permeable: allows water to flow through --leaching: salts, minerals and nutrients washed out of soil

Air 1. roots need air to breathe 2. soil must have air in pores for plants to grow

Soil Structure A. Aggregates: large particles of soil B. Soil structure: way in which aggregates are arranged --affects water and air movement in soil, nutrient availability and microorganism activity --structure can be destroyed by compaction (driving heavy equipment over, working soil when it’s too wet or too dry)

Soil Structure --8 categories 1. granular 2. crumb 3. platy 4. prismatic 5. massive 6. columnar 7. blocky 8. single grain

Soil Profiles view of a cross-section of soil --show layers of soil (horizons)

Soil Profiles 4 main horizons A. O horizon: (not main): organic matter (leaves, roots, limbs, decaying matter) on surface B. A horizon: topsoil, top layer of soil --contains greatest amount of decomposed O.M. --fertile --0 – 10 inches

Soil Profiles C. B horizon: subsoil, few nutrients, low O.M., some plant roots anchor here D. C horizon: parent material, weathered bedrock, and leached materials. No roots or O.M. E. R horizon: bedrock or solid rock