How Soil Forms

topsoil; dark soil rich in humus and contains the most organic matter

• A horizon

• B horizon

• C horizon

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1

subsoil; below the A horizon; contains clay and other minerals

• A horizon

• B horizon

• C horizon

contains partially weathered rock

• A horizon

• B horizon

• C horizon

each layer of soil that differs in color and texture from the layers above and below it

• soil

• soil fertility

• soil horizon

a loose weathered material, a mixture of rock fragments, organic material, water, and air that can support the growth of vegetation

• soil

• soil fertility

• soil horizon

Tags

NGSS.MS-LS2-3

describes how well a soil can support plant growth

• soil

• soil fertility

• soil horizon

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

dark, organic material formed in soil from the decayed remains of plants and animals

• sand

• silt

• clay

• humus

Tags

NGSS.MS-LS2-3

largest particle in soil; feels coarse

• sand

• silt

• clay

• humus

smaller than sand particles; feels smooth and silky

• sand

• silt

• clay

• humus

smallest soil particle; feels smooth and sticky

• sand

• silt

• clay

• humus