Book 5, Question 66
More Than Mud! Why Is Soil More Than Dirt?
Soil is a mix of tiny bits of rock, air, water, and rotted plant and animal material. It is also home to worms, insects, and lots of tiny living things. That mixture is what helps plants grow.
From the book
Page from A Million Whys Book 5
More fun facts
- Most people use the words dirt and soil to mean the same thing, but soil scientists do not.
- Soil builds up in layers over time.
- To soil scientists, dirt is simply soil that has been moved out of its place.
- Soil is home to living organisms, so scientists think of it as a living system.
- Plant roots trade water, gases and nutrients with the soil around them.
- NASA's SMAP satellite measures how much water is in soil around the world.
Sources: Science News Explores, NASA Science, NOAA, U.S. Department of Energy
Questions kids ask
What is the difference between soil and dirt?
Soil is where it belongs, full of life. Scientists say dirt is soil that has been moved somewhere else.