Soil Types & Layers

Which of the following is NOT one of the three layers of soil?

• topsoil
• undersoil
• subsoil
• bedrock

Which of the following is NOT one of the three types of soil?

• clay
• sand
• silt
• mud

_______ is the type of soil used most often with plants. It is a mixture of clay, sand, and silt.

• loam
• humus
• mud
• dirt

Humus is.....

• the dead parts of plants and animals in soil.
• A food we eat with pretzels.
• The tiny particles inside of soil
• The roots that come off of a plant and live in soil.

Ellen grabs a topsoil sample in her hand. She rolls it into a ball. The soil feels gritty and the ball falls apart. What part of the topsoil most likely made the topsoil feel gritty?

• clay
• sand
• silt
• humus

When there are not enough plants to hold topsoil in place, water and  _______ carry the topsoil away, leaving the subsoil exposed

• sunlight
• birds
• magnetic fields
• wind

When plants, animals, and other organisms die, they break down and become part of the soil. What is this part of the soil called?

• sand
• silt
• clay
• humus

Which of the following is the largest particle in soil?

• sand
• silt
• humus
• clay

Many plants cannot grow in clay soil. Why is this true?

• Clay soil does not have many nutrients.
• Roots cannot easily push through clay soil.
• Water doesn't drain well through clay.
• All of these choices.

You dig a small hole in the soil and the next day it rains. The hole fills with water, but does not empty even after several days of dry weather. What is the soil mostly made of?

• clay
• sand
• humus
• silt