3rd Grade Soil Test

What is erosion?. making rocks bigger with weather. water breaking rocks down and taking them with it. ears breaking down. houses breaking down.

What are the layers of soil from the surface down?. topsoil, subsoil, bedrock. bedrock, topsoil, subsoil. topsoil, bedrock, subsoil. topsoil, lava, subsoil.

What is a natural resource that plants use to grow?. soil. humus. trees. rock.

How does new soil form?. when plants grow. when rocks rub together or weathering. when water comes together or condensation. All of the Above.

What is bedrock mostly made of?. rocks. soft dirt. clay and sand. loam.

Humus is a type of ______ that is mostly made out of __________?. soil, dead plants. dead plants, rocks. loam, sand. sand, rocks.

What kind of soil is loam?. deep brown, variety of grains. beige grains that slip through your fingers easily. reddish brown or yellow grains that clump together. bedrock.

What type of soil is clay?. deep brown, variety of grains. beige grains that slip through your fingers easily (does not hold water well). reddish brown or yellow grains that clump together (holds water well). bedrock.

What is sandy soil?. deep brown grains best for gardening. beige grains that are not good for gardening. reddish brown grains that don't hold water. yellow grains that don't hold water.

What is subsoil?. Subsoil contains minerals washed down from above. It is a mixture of rock and soil. Only large tree roots grow on this level. Subsoil is the soil at the surface near the grass. It is made up of large rocks and soil. Only smaller tree and plant roots grow on this level. Subsoil contains soil washed up from below. It is a mixture of bedrocks and soil. No tree roots grow on this level. All of the above.

Why do we need the soil's nutrients?. plants soak up water that comes from the soil. erosion breaks down water. soil produces electricity. nutrients in the dirt evaporate.

What holds plants in place and gives them nutrients?. sun. soil. people. earthworms.

Soil contains: rocks, clay, humus, and sand. rocks and clay, but never sand. clay and sand, but never humus. clay and sand, but never rocks.

Farmers work hard to prevent soil erosion. Soil erosion happens when: too many plants grow in the soil. too many rocks are in the soil. too many earthworms make holes in the soil. topsoil is carried away by wind and water.

If humus is made from decaying _______ , that means that ________ plants give nutrients to the soil. plants, dead. plants, living. rocks, living. rocks, flowering.

If you put most plants in sand, what will happen?. It will not grow very well. It will not get many nutrients. Because sand does not hold water very well, the plant will not get much water. All of the above.

Humus is part of __________ . topsoil. subsoil. bedrock. All of the above.

What can stop erosion?. tree and plant roots. walking on the same path over and over again. building your house next to the beach. water in rivers.