Unit B Section 3 Introduction Healthy, Rich Soil

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Section 3: Plants rely on healthy, rich soil in order to grow.

Key Ideas   Unit Checklist

  Unit B: Section 3 – Introduction

The Dust Bowl

During the 1930s, the whole world was in an economic depression  when jobs were few, money was scarce, and goods difficult to obtain. At the same time, a severe drought occurred on the Canadian and American prairies. Crops did not grow because of very little rain.

On the farms, dry soil was not covered by plants. The wind blew the dry topsoil into gigantic dust clouds. The 1930s are sometimes called the Dirty Thirties because of the huge dirty dust storms, and the prairies were known as the Dust Bowl.

Dust storms were caused partially by unsuitable farming practices that promoted erosion. Erosion involves soil being moved by wind or water from one location to another. Farmers plowed the soil, removing natural prairie grasses to prepare for crops such as wheat. Soil was made bare in preparation for planting; no leaves or residue (straw) was left to prevent the wind from blowing away the soil.  The topsoil was exposed to erosion by wind.

When the nutrient-rich topsoil was blown away, crops were even more difficult to grow. Many farmers had to leave their farms and move to the cities for work.

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 Watch More

Dust Bowl

This video shows pictures and videos from the Dust Bowl of the 1930s. It includes some interviews with elderly adults who were young during those Dust Bowl years.

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  Words to Think About:

Check out the word cloud below. It pictures the important words that you are going to learn in this section. Watch for these words, and combinations of these words, as you read. When you see them highlighted, you can click on them to learn more about what the word means. You can also visit the course glossary and read definitions for all of these words.

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Lessons in This Section

Lesson B10: Types of Soil

Lesson B11: Human Use of Soil

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  Try It!

Soil Erosion by Water

Try this simple experiment to see how soil erosion is caused by water.


Materials:

• empty large plastic pop bottle
• scissors
• soil
• juice pitcher
• water
• glass cup
  

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Instructions:

1. Lay the pop bottle on its side.
   
   
2. Using scissors, cut a hole on one side of the pop bottle. The hole should be big enough to scoop soil into.
   
   
3. Fill the pop bottle nearly half full with soil – to just below the level of the pop bottle spout.
   
   
4. Place the pop bottle on the countertop so the spout is over the edge of a sink. Place a glass cup in the sink under the pop bottle spout.
   
   
5. Fill a juice pitcher with water. Pour water slowly into the hole in the pop bottle so that water fills the soil. Pour water slowly until you notice water starting to drip from the pop bottle spout into the glass cup.
   
   
6. Observe the water in the glass cup. What do you notice?
   
   

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Questions:

Think about the following questions very carefully. Then, type or write your answers. When you have your answers, click the questions for feedback.