Soil Conservation

SOIL CONSERVATIONSection 3

Ms. Musich

Activating Prior Knowledge Think of an area of land that has a wide

are of dirt like a construction site or a vacant lot…

What do you think happens to an area like this when it rains?

What is the water like that runs off the area?

Is there anything that could be done to prevent this erosion of soil?

If you were in the 1800s… You would have seen lots of prairies on

your settler’s journey. (Think Oregon Trail)Prairie soil is very fertile and is rich with humus.

Sod –the thick mass of tough roots at the surface of the soil keeps it in place and holds onto moisture.

The Value of Soil Soil is one of Earth’s most valuable

resources because everything that lives on land depends directly or indirectly on soil.

Plants depend on soil to live and grow. Animals depend on plants (or animals that eat

plants) for food.

Soil formation can take hundreds of years for just a few centimeters of soil to form.

The Value of Soil (cont’d) Fertile soil is very valuable because less

than one-eighth of the land on Earth has soil that is well suited for farming. What does it mean for soil to be fertile? What substance must be in soil for it to be

fertile?

Soil Damage and Loss Soil is so important, but can be damaged

or lost. Soil can lose its fertility. This happened in the South in the late

1800s when cotton was the only crop grown on farms.

In the early 1900s, George Washington Carver developed new crops and farming methods to make the soil fertile again.

Fertile vs. Not

George Washington Carver1864-1943

The Dust Bowl As settlers began settling among the

Great Plains, they began plowing the earth.

Why do you think these settlers plowed the earth?

The Dust Bowl Plowing removed the grass from the

Great Plains and exposed the soil. In times of drought, the topsoil quickly dried out, turned to dust, and blew away.

Soil Conservation After the Dust Bowl, people began to

realize how important soil is and developed new farming techniques.

Soil conservation is the management of soil to prevent its destruction.

Two ways that soil can be conserved include contour plowing and conservation plowing.

Contour Plowing

Contour plowing is the practice of plowing fields along the curves of a slope.

This helps slow the runoff of excess rainfall and prevents it from washing the soil away.

Conservation Plowing

Conservation plowing disturbs the soil and its plant cover as little as possible.

Dead weeds and stalks of the previous year’s crop are left in the ground to help return soil nutrients, retain moisture, and hold soil in place.