Subsoil is the layer of soil under the topsoil on the surface of the ground. Like topsoil, it is composed of a variable mixture of small particles such as sand, silt and clay, but with a much lower percentage of organic matter and humus,and it has a small amount of rocks which are smaller in size mixed with it.
What are the 5 layers of soil?
Layers of Soil
- The O-Horizon.
- The A-Horizon or Topsoil.
- The E-Horizon.
- The B-Horizon or Subsoil.
- The C-Horizon or Saprolite.
- The R-Horizon.
- Recommended Video:
- Tensiometers.
What is there below the soil?
The subsoil may contain some broken down organic matter but it is mostly made of weathered rocks and clay minerals. Plants send their roots into both of these layers to find water stored in the soil and to find nutrients that they need to grow and to use for photosynthesis.