1. Soil Horizon

2. Horizon Horizon is a side profile of the layers of soil
Soil usually has 3 main layers, and one above and one below (5 total)

3. Soil Horizons Diagram Copy this into your notes O Horizon: LitterN
A Horizon: Topsoil
B Horizon: Subsoil
C Horizon:
Parent Material
R Horizon: Bedrock

4. O Horizon: Litter Not really a layer of soil
It’s on top of the first layer of soil
Contains grass, plants, and animals

5. A Horizon: Topsoil 1st layer of soil
Darkest layer of soil (dark brown or black)
Contains humus which is decayed plants and animals
The darker the soil, the more nutrients it contains

6. B Horizon: Subsoil 2nd layer of soil
Reddish brown in color; contains a lot of clay
Fewer nutrients and water
Limited plant growth

7. C Horizon: Parent Material
3rd layer of soil
Lightest in color (gray)
No nutrients, animals, or plant growth
Contains weathered rock and sediment

8. R Horizon: Bedrock Below the last layer of soil Solid rock – no soil
Has not been weathered or broken down yet

9. Properties of Soil
Texture – determined by the size of the weathered rock particles it contains
Sand – largest
Silt – smaller
Clay - smallest
Color – most come from iron content and humus
Pore Space – how much air and water it can hold
pH – how acidic is the soil