Contributor: Hannah Brooks. Lesson ID: 12448
Is soil just plain old dirt, just there to hold you up? There are different types of soil based on the size of the particles that make it up. Go outside and get to know the soil in your neighborhood!
Soil looks different because it contains different amounts of minerals, but also different amounts of other materials.
Soil contains three types of particles: sand, silt, and clay. The combination of these three particles defines the soil texture.
Clay is the smallest type of particle found in soils. These tiny particles can fit tightly together, leaving very little space in the soil for other substances.
Sand is the largest soil particle, which means you can easily see each grain of sand.
This space changes the characteristics of the soil.
Silt, the third type of particle, is larger than clay but smaller than sand.
Soils contain some amount of each of these three types of soil particles.
When the soil has too much sand, water runs through it easily, removing nutrients.
Soils with a high amount of silt are easier to pick up and erode but also are easily pushed together.
Clay-based soils prevent water from flowing through because of the small particle size.
A healthy soil combines all three particles so water can move through it slowly, leaving important nutrients and materials in the soil.
Review what you have learned, and write down the soil particles in order of increasing size.
In the Got It? section, you will explore the size of soil particles.