A Riddle… I am light and I am heavy. I am strong enough to hold up a skyscraper. I am fragile enough to be blown away in the wind. I am an anchor. I am a home. I am a sponge. I am one substance made of many different things. I am loose enough to flow like a river. I am solid as a mountain. I can be fertile. I can be barren. I am living and I am dead. What am I? DIRT!

The “DIRT” On Soil! Pam K. Roach Kennesaw State University ECE 8814/01

Dirt or Soil……What’s the Difference? Dirt is what you get under your finger nails. Soil is what we stand on and plant in.

Table of Contents What is soil? Major soil types Layers of soil How do soils differ? Why is soil important? How soil is harmed? How can people conserve soil? What’s your soil IQ? game (hyperlink) Glossary

Georgia Performance Standards

What is Soil? Soil is a complex, living system, composed of living and non-living materials, comprising a very thin layer on Earth.

Living and non-living components interact, change, and combine over thousands of years to create soil.

Soil is the loose material on the upper layer of the Earth. Soil is formed from: air water Rocks and minerals humus

Major Soil Types Clay – has small grains and holds water easily Sand – has large grains and large air spaces between the grains allowing water to leave quickly Loam – has large and small grains, lots of humus, holds enough water for plants but also drains well

Soil takes a long time to form: It takes about 500 to 1,000 years to make just 2.5 centimeters (1 inch) of soil. Deep soil takes thousands of years to form.

Soil Forms in Layers Topsoil is made up of the smallest grains and the most humus…it is the richest layer of soil. Subsoil has larger grains and less humus than topsoil. Bedrock is the solid rock under soil. It is made of different minerals in different places.

How Do Soils Differ? By their color – soil can be black, brown, gray, red, yellow or white By their grain size – some soil has large grains and feel gritty, others have small grains and feel smooth and powdery By the minerals they contain By the amount of water they hold

Why is Soil Important? Soil is important to all living things It contains the minerals all living things need, it’s part of the circle of life.

Soil is Important to Plants and Animals Soil provides a home to many animals. Soil provides the minerals that plants need to grow. Soil provides the foods we need to eat!

Dig Deep! Scoop up some soil, what might you see?

Soil Helps Provide Plants With: Support Nutrients Water Air All of these are necessary for a plant’s life. SOIL

What Makes up our Topsoil?

How Soil is Harmed By cutting down too many trees Planting the same crop for many years on the same land (over-cropping)

How Can We Conserve our Soil? Soil is a natural resource that we cannot live without! Farmers use various methods to conserve the soil and use it wisely: Strip cropping Contour plowing No-till farming

Check out this websites to see if you know the “dirt on soil”! games.html# games.html# Play the What’s Your Soil IQ? Game, Good Luck! Click on this website to see how scientists use new techniques to study the soil to learn more about earthquakes….ZOWIE!!!! (right click on the sight and open up the hyperlink)

Glossary bedrock: layer of solid rock under soil clay: soil that has small grains and hold water easily conservation: saving resources by using them carefully humus: material made up of decayed parts of once-living things loam: rich soil with a lot of humus resource: material found in nature that living things use topsoil: richest layer of soil strip cropping: planting strips of thick grass or clover between strips of crops contour plowing: planting rows of crops around the sides hills instead of up and down