1. SOIL HORIZONS

2. SOIL HORIZONS This is a typical mature soil profile.
Notice the Horizons
that are present in
this profile: O, A, B, C
What Horizons are
missing from this picture?

3. O HORIZON
The O Horizon contains layers of Organic material, such as leaves, pine needles and twigs and decaying animal tissues.

4. A HORIZON The dark color of the A Horizon is from the mixing of Humus
(Organic Matter)
with weathered minerals.

5. E Horizon
E Horizon: E stands for “egg beater” which is the movement of dissolved or suspended materials out of the A Horizon.
It is lighter in color than the layers above or below it.

6. B HORIZON B Horizon: Commonly called Subsoil.
The ignorant zone, where containing soil materials leached from above. Color: yellow or red.

7. C HORIZON
C Horizon: Partially weathered parent material and mineral particles are in this horizon.

8. R HORIZON
R Horizon: Unaltered bedrock within a few feet of the surface.
(Dolomite, dolostone, or limestone.) Typically requires blasting to dig through.

9. In the Real World: Soil Profiles are as different as people!
Every state has dozens of Soil Profiles.

10. Can you identify the Horizons?B. C. D. E. F.

11. Can you identify the Horizons?

12. What is a typical
mature soil profile?