It's a sunny summer day. When you step outside, you're surrounded by signs of life: leaf–filled trees, glowing green grass, scampering squirrels, swooping birds, buzzing bees. But that's not all! If you look down, you might see another super–important part of nature: the soil beneath your feet. Soil is the root of all life. And it's far from just dirt.
Soil is a rich and varied substance, with an amazing past, a very important present, and a future that depends on us. Let's take a look!
Not Just Dirt
Soil plays an important role in our life and in the life of all living things. It gives plants what they need to grow. It helps recycle waste and dead things into materials that can support new life. It holds and cleanses water. It forms a surface for our houses, highways, and us. And it provides a home for millions of living things.
Scoop up a handful of soil and hold it close to your face. What does it feel like? What does it smell like? What does it look like?
Soil is a mix of minerals, organic matter (formerly living things), air, and water. In Minnesota, rocks and other materials carried by glaciers 11,000 to 14,000 years ago form the basis for our soils. But a lot has happened since then. Water, wind, and roots have pulverized the rocks. Wind, rain, people, and other living things have added more ingredients, mixed things up, broken things down, and moved things around. Gravity has moved soil particles down slopes. You can do a lot in 11,000 years!
Because soil ingredients vary from place to place, the texture, color, and structure of soil does, too. A soil might feel coarse like sand, soft like silt, or sticky like clay. Depending on the rocks and minerals that make it up, it might be black, red, white, brown, or orange. It might hold lots of food for plants or be like an empty pantry. The particles might be loose, with lots of space for air and water in between, or they might be packed so tightly together that you need a hammer to break them apart.