What is the common name for Horizon A?

• bedrock
• topsoil
• parent material
• subsoil

What is humus?

• organic material rich in nutrients
• subsoil
• parent material
• trees

Why is soil an important natural resource?

• soil is used to make buildings
• soil can grow crops
• soil comes from bedrock
• soil is full of mircobes

Subsoil is made mostly of

• parent material
• humus
• clay and silt
• bedrock

What is the main purpose of microbes in the soil?

• to release the nutrients in rocks
• to cause disease
• to feed animals

Which describes the soil layers in order from the surface?

• top soil, bedrock, horizon C, subsoil
• top soil, subsoil, horizon C, bedrock
• top soil, horizon C, subsoil, bedrock

Why are good conservation practices important for lumber companies to follow?

• It adds groundwater
• it increases soil erosion
• it decreases soil erosion
• the soil is shaded

Which of these slows down soil erosion on construction sites?

• clear cutting
• strip mining
• contour plowing
• sandbags and nylon fencing

Two methods of soil conservation in farming are

• reclamation and subsurface mining
• landscaping and nylon fencing
• selective harvesting and replanting
• contour plowing and windbreaks

What type of erosion is slowed down by contour plowing and terracing?

• wind
• water
• air