Soil Layers - Quiz 1

The O Horizon contains mostly..

• Organic Matter

• Rocks

• Boulders

• Houses

Answer explanation

Remember that the O Horizon is made up mainly of organic matter such as leaf litter. A trick to remember..... O Horizon & (O)rganic.

Reorder the following soil layers from BOTTOM layer to TOP layer.

• Parent Material

• Bedrock

• Subsoil

• Topsoil

• Humus

The A Horizon is to the ​ (a)   , the B Horizon is to the ​ (b)   .

• topsoil
• subsoil
• parent material
• humus

Answer explanation

The A Horizon belongs to the topsoil, containing rich organic matter, microorganism activity and the place where seed germination takes place.

The B Horizon belongs to the subsoil, containing less humus and organic matter, it is more compacted, and good at storing water!

The R Horizon contains mostly ​ (a)   ​

• solid rock
• Humus
• Organic Matter
• Broken tree roots
• Microorganisms

Answer explanation

The R Horizon is the bottom layer of the soil, containing solid rock, and sheets of granite, quartzite, basalt and sandstone.

Match the following soil horizons to their features.

• organic matter and leaf litter

• O Horizon

• large broken rocks, broken tree roots

• B Horizon

• more compacted soil

• A Horizon

• rich in organic matter, where seed germination takes place

• C Horizon

• pale color, leaching nutrients from upper layers

• E Horizon

Circle the E Horizon

Answer explanation

The E Horizon is recognizable for it's change in color and texture.

The color is not as deep because of there being less organic matter.

Which is NOT a layer of the soil?

• Topsoil

• Subsoil

• Bottom Soil

• Parent Material

Answer explanation

Bottom soil is NOT a layer of the soil.

What do the capital letters associated with the soil layers mean? (ie. O, A, E, B, C, R)

What does their association with the layers represent?

Answer explanation

These letters are the base characterization where the certain soil layers is and what materials it is made up of.

Most layers only require one capital letter as a description, however two or three can happen depending on the soil and the soil make up.

A soil profile is usually studied to a depth of _________________.

• 6-12 inches
• 1-2 feet
• 3 to 5 feet
• 8-10 feet

What is HUMUS made from?

• The remains of decayed plants.

• Both

• The remains of decayed animals.