Introduction to Soil

SOIL Geologic definition: Loose surface of the earth as distinguished from solid bedrock; support of plant life not required.

Soil out of place and unable to serve it’s purpose Dirt Soil out of place and unable to serve it’s purpose

Foundation for roads and structures Home to plants and animals Importance of Soil Foundation for roads and structures Home to plants and animals Grow things in it Contains and filters water Helps dispose of waste Basis for recreation areas

Soils Perform Several Vital Functions Sustaining plant and animal life below and above the surface Regulating and partitioning water and solute flow Filtering, buffering, degrading, immobilizing, and detoxifying Storing and cycling nutrients Providing support to structures

Mixture of mineral matter, organic matter, water, and air. Properties of soil SOIL

SOIL COMPONENTS Air 25% Mineral Matter 45% Water 25% Organic Matter 5%

3 Fractions of Mineral Matter Sand Silt Clay

Soil Color Indicator of different soil types Indicator of certain physical and chemical characteristics Due to humus content and chemical nature of the iron compounds present in the soil

Want to learn more about soil? Visit NRCS’ website at the National Soil Survey Center at www.soils.usda.gov