The O Layer or O horizon is also known as the Organic horizon.
It describes the topmost layer composed of organic matter, such as dead plants and animals!
The A horizon, also known as topsoil is where most plant roots grow!
It is rich in nutrients and typically dark in color. Humus is found in this layer and consists of the decomposed remains of dead plants and animals that have been broken down
it aids greatly in fertility of plants.
The B horizon also known as subsoil lies beneath the A horizon and is lighter than the A horizon!
It is made of a combination of sand, silt, and clay and often contains minerals which have leeched down from the higher layers.
The C horizon contains parent material, and consists of unweathered rock which the other soil layers are made of.
This layer is where you will find regolith which is loose rocky material that has been broken down through weathering.
The R horizon is also known as bedrock, it is the layer of soild rock that lies at the bottom of all soil, providing structural support for the layers above it.
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