Soil Formation and Composition
E.SE.06.13 - Describe how soil is a mixture, made up of weather eroded rock and decomposed organic material.
E.SE.06.14 - Compare different soil samples based on particle size and texture.
E.SE.06.14 - Compare different soil samples based on particle size and texture.
Soil: The loose, weathered material on the Earth’s surface in which plants grow.
Soil forms as rock is broken down when weathering mixes with other material on the surface.
Bedrock: is the solid layer of rock beneath the soil.
Soil is the mixture of rock particles, minerals, decayed organic materials, air, and water.
Humus: a dark-colored substance that forms as plant and animal remains decay.
Loam: Soil that is made up of about equal parts of clay, sand, and silt.
Soil Horizon: a layer of soil that differs in color and texture from the layers above or below it.
Topsoil: A crumbly, dark brown soil that is a mixture of humus, clay, and other materials.
Subsoil: Consists of clay and other materials washed down from the A horizon, but little humus.
Some soil organisms mix the soil and make spaces in it for the air and water. Other soil organisms make humus, the material that makes soil fertile.
Litter: A loose layer of dead leaves formed when plants shed leaves.
Decomposers: the organisms that break down the remains of other dead organisms.
Topsoil (humus, clay, dark brown soil)
A Horizon_______
Subsoil (mostly clay mixed with other materials- little humus)
B Horizon_______
More Rock/Rock Fragments
C Horizon______
Bedrock
Soil forms as rock is broken down when weathering mixes with other material on the surface.
Bedrock: is the solid layer of rock beneath the soil.
Soil is the mixture of rock particles, minerals, decayed organic materials, air, and water.
Humus: a dark-colored substance that forms as plant and animal remains decay.
Loam: Soil that is made up of about equal parts of clay, sand, and silt.
Soil Horizon: a layer of soil that differs in color and texture from the layers above or below it.
Topsoil: A crumbly, dark brown soil that is a mixture of humus, clay, and other materials.
Subsoil: Consists of clay and other materials washed down from the A horizon, but little humus.
Some soil organisms mix the soil and make spaces in it for the air and water. Other soil organisms make humus, the material that makes soil fertile.
Litter: A loose layer of dead leaves formed when plants shed leaves.
Decomposers: the organisms that break down the remains of other dead organisms.
Topsoil (humus, clay, dark brown soil)
A Horizon_______
Subsoil (mostly clay mixed with other materials- little humus)
B Horizon_______
More Rock/Rock Fragments
C Horizon______
Bedrock
Layers of Soil
Soil Conservation
Dirt Detective: Trees & Soils Walk
Do trees have preferences? Predict what trees will thrive in particular soils and pH levels. Grab your pH kit and dig in!
From the Smithsonian National Zoological Conservatory
From the Smithsonian National Zoological Conservatory