Soil Horizon
S
Horizon
S Horizon is a side profile of the layers of
soil
S Soil is usually divided into 3 main layers,
but will also include the layers above and
below for a total of 5 layers.
Soil Horizons Diagram
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O Horizon: LitterN
A Horizon: Topsoil
B Horizon: Subsoil
C Horizon:
Parent Material
R Horizon: Bedrock
O Horizon: Litter
S Not really a layer of soil
S It’s on top of the first layer of soil
S Contains grass, plants, and animals
A Horizon: Topsoil
S 1st layer of soil
S Darkest layer of soil (dark brown or black)
S Contains humus, plant roots, small animals,
water, and nutrients for plant growth
S The darker the soil, the more nutrients it
contains
Types of Topsoil
B Horizon: Subsoil
S 2nd layer of soil
S Lighter in color (reddish brown)
S Fewer nutrients and water
S Limited plant growth
C Horizon: Parent Material
S 3rd layer of soil
S Lightest in color (gray)
S No nutrients, animals, or plant growth
S Contains weathered rock and sediment
R Horizon: Bedrock
S Below the last layer of soil
S Solid Rock
S Has not been weathered or broken down
yet
S No soil in this layer