Book 24, Question 128
How do scientists take a core sample of soil?
A soil corer is a hollow metal tube that is pushed or hammered into the ground. When it is pulled out, it holds a column of soil with all the layers in order. Scientists look at the colors, the texture, and the roots in each layer. It is a fast way to study the ground without digging a big hole.
More fun facts
- A soil probe pulls up soil in one continuous core from the surface down, while disturbing the soil very little.
- A probe is the best tool for sampling soil, and it is faster than digging with a shovel.
- Sampling tools should be stainless steel or chrome plated, because brass, bronze or galvanized tools can add copper or zinc to the soil.
- A probe does not work well when the soil is too wet, because the soil squashes, or too dry, because it is hard to push in.
- For a home soil test, people take cores 4 inches deep in lawns or 6 to 8 inches deep in gardens from 8 to 10 random spots.
- The cores are mixed together in a plastic bucket to make one sample.
- Even a small amount of lime or fertilizer on the tools can spoil a soil sample.
Questions kids ask
How can you tell if soil is too wet to sample?
Squeeze some into a ball. If it breaks apart easily, you can sample, but if it is good for making mud pies, it is too wet.