1. The Ground Beneath Our Feet
S6E5h. Describe soil as consisting of weathered rocks and decomposed organic material.

2. What Makes Up Healthy Soil?
Mineral fragments, humus, air, water, and living things such as
Plant roots, Insects, Worms
Humus
Organic Material
Forms from decayed plant and animal material
Can support the growth of vegetation
Parent rock
The source of mineral fragments in the soil

3. Soil Formation Soil starts out as rock
The surface rock breaks down into smaller pieces and is mixed with organic matter.
Over time this creates a thin layer of soil.
Decaying matter makes the soil thick and rich

4. Soil Formation Video

6. Soil Particles

7. Different Types of Soil
Every soil type is a mixture of sand, silt, clay.
The right mixture is called loam.
Loam =
40% sand
40 % silt
20 % clay

8. Soil Profile The vertical display of soil horizons.
Each soil profile is different from another.

9. What is a Soil horizon? O - Litter from dead plants & animals A
Topsoil E
Zone of intense leaching. B
Collects dissolved substances from upper horizons (sub soil) C
Weathered bedrock R
Bedrock

10. Review Questions Which particle is the biggest one that goes in soil?
A. Clay
B. Silt
C. Quartz
D. Sand

11. Review Questions 2. Horizon C is made mostly of A. Humus
B. Organic Material
C. Bedrock
D. Weathered Rock O A B C

12. Review Questions 3. What is loam?
A. Loam is the perfect mixture of 40 % sand, 40% silt, and 20 % clay.
B. Loam is the combination of 30% sand, 40% mud, and 30% clay.
C. Loam is located in horizon B.
D. Loam is the particle quality of any soil.

13. Review Questions 4. What is missing from this profile? A. Humus
B. Organic Material
C. Bedrock
D. Weathered Rock O A B C

14. Review Questions 5. How does soil start?
- A. A large rock is weathered
- B. Bits & pieces of rocks are cemented together
- C. Decaying matter is compacted together
- D. None of the above

15. Review Questions
1. Which particle is the biggest one that goes in soil?
A. Clay
B. Silt
C. Quartz
D. Sand

16. Review Questions 2. Horizon C is made mostly of A. Humus
B. Organic Material
C. Bedrock
D. Weathered Rock O A B C

17. Review Questions 3. What is loam?
A. Loam is the perfect mixture of 40% sand, 40%silt, and 20% clay.
B. Loam is the combination of 30% sand, 40% mud, and 30% clay.
C. Loam is located in horizon B.
D. Loam is the particle quality of any soil.

18. Review Questions 4. What is missing from this profile? A. Humus
B. Organic Material
C. Bedrock
D. Weathered Rock O A B C

19. Review Questions 5. How does soil start?
- A. A large rock is weathered
- B. Bits & pieces of rocks are cemented together
- C. Decaying matter is compacted together
- D. None of the above