Getting the Dirt on Dirt!

Let’s Talk Science Partnership Program!

Getting the Dirt on Dirt!

Activity Book

Name: ______

What is dirt?

Dirt (or soil) is a combination of many things. Some of the things included in soil are:
minerals (for example: quartz, silica, iron, mica)

decomposing plant material
bacteria
fungi

Dirt is also home to many types of animals. Many types of insects, as well as earthworms, moles, and other small animals live underground.

Dirt is also important to people for many reasons. We need dirt to grow crops for food, and trees to produce oxygen for use to breath. Dirt also acts like a sieve by filtering chemicals and bacteria out of our water.

Dirt seems to be everywhere around us, but it is important to know that very little of the earth is covered by soil that can produce food.

There are many different types of soil. Scientists use “texture” to classify dirt. Soil texture is the way soil feels in your hands. Sand feels gritty. That is because sand particles are very big. Silt feels very soft, like flour. This is because silt particles are very small. Clay feels very sticky in your hands. Clay particles are the smallest of all. If you had a grain of sand as big as a barrel, the clay particle would be the size of a coin.

Barrel Plate Coin

(sand) (silt) (clay)

Activity #1: What is soil made of?

Soil is made of many different things. In this experiment we will look at different types of soil to see what they are made of

Soil Layers:

Step 1: Put some dirt into one glass jar. Put some sand into another jar. Fill the jars with water and put the lid on tightly.

Step 2: Shake the jars up so that the water looks muddy. Put the jars on a table and leave them for 30 minutes.

What has happened to the soil? ______

How many layers do you see? ______

Does the jar with the sand look different? ______

______

What is in your dirt?

Look at the three types of soil under the microscope.

Make a list of some of the things you see in each dish:

Dirt / Compost / Sand

Did you find any animals? ______

Activity #2: What type of soil is better for growing plants?

Plants need light and water in order to grow, but is that all? We will try to grow plants in three types of soil.

Step 1: Fill one pot with compost, packing the soil down lightly. Fill another pot with sand. Fill a third pot with dirt from the forest. Label the three pots “Sand,” “Compost,” and “Dirt.”

Step 2: Sprinkle a few radish seeds in each pot and cover them with soil. Water lightly and leave on a window sill

Step 3: Make predictions! Scientists make predictions (called “hypotheses”) as a way of seeing if the results of their experiments are the same as what they predicted.

Hypothesis: What plant will grow the biggest? ______

Why? ______

______

Results: Record the height of each plant once a week.

Date / Sand / Compost / Dirt

Questions:

Which plant grew the biggest?

______

Is this what you predicted?

______

What did some plants grow bigger than others?

______