How Does Soil Form?

Lesson Plan - Get It!

Audio:

Cave formations can take thousands of years to form.

• Did you know soil can take hundreds of years to form?

While it may seem like a simple process to create soil, it involves many different factors working together. Soil formation starts with the bedrock or parent material.

This is the rock matter that can be found in an area. Think of the parent material as a base that the loose soil builds on top of, like dust on a shelf!

The parent material contains minerals and elements that can be broken down and will build up in the soil above. It can determine what kind of soil forms in an area.

The climate in an area can also impact soil formation. Precipitation and temperature can determine how quickly the parent material is broken down through weathering.

The landscape can also impact the formation of soil. If an area has a steep slope, the soil will often move downward with water and gravity, changing the soil type along the slope and at the bottom of the feature.

Soil takes a long time to build up, so time plays an important part in soil formation. It is important to give the soil time to rebuild and develop so it is nutrient-rich and can support life!

This is one reason farmers leave the fields empty during off-seasons so the soil can become productive again.

Living organisms in the soil help to add important chemicals to keep the soil healthy. They move water and air throughout the soil, providing resources for plants and other animals.

These organisms help soil develop!

Soil forms over time, growing just like you. It grows up from the parent material, slowly developing based on the minerals, organic matter, landscape, and climate in an area.

Each of these factors influences the type of soil formed and the time it takes to develop.

In the Got It? section, you will create a graphic organizer that digs deeper into the factors affecting soil formation.