Soil

SOILSOL 3.1 & 3.7

Soil provides

support and nutrients

for plant growth

EROSIONis the movement of sediment and

rock to new places.

Weatheringbreaks down rocks to create soil.

It can be caused by weather, water, or living things

There are five components of soil:

• 1. Rock

• 2. Sand

• 3. Silt

• 4. Clay

• 5. Humus

• Can you match each type of soil to its picture?

RockRock is solid and made of minerals

Sand

Sand is tiny grains of worn down rock. It doesn’t hold water or have many nutrients.

Silt

Silt is very small, broken pieces of rock. It is larger than clay, but smaller than sand. It

is powdery when dry.Sand ------------Silt---------------Clay

(smaller particles) (larger particles)

CLAYClay holds water well. It is sticky and can be

shaped when it is wet. But, it is very hard when dry.

Clay has many nutrients.

Clay is used for adobe or brick houses.

Humus

Humus is made of leaves, twigs, small animals, or other decayed substances.

Humus adds many nutrients to the soil.

Humus is in the topsoil.

3 Layers of Soil

1. Topsoil (The layer on TOP)

2. Subsoil (The prefix SUB means under)

3. Bedrock (It’s hard as rock down there!)

Natural Resources

• Made by NATURE

• Cannot be replaced

• Must be conserved (saved)!

Ways to Conserve Soil

• Plant trees

• Plant grass

• Healthy farming

• Plant gardens to grow crops

• What else can you do to conserve soil?