Chapter 2G

4. organic material
6. organism that breaks down soil
8. layer that plants get planted in
9. anything natural that humans use
12. wears away physically
17. layer of dead plants, leaves, and soil
18. map that shows surface features
19. plowing the edges of slopes to prevent soil loss
20. ice, water, wind, or gravity that moves weathered soil or rock
21. heavy line that shows round units
22. layer of soil that differs in color and texture from the layers around it
23. management to prevent soil destruction
27. loose material that plants grow in
28. thick mass of grass roots and soil
29. the line that shows increasion from one line to another

1. cause of potholes
2. a line that shows levels of elevation
3. the characteristic of a mineral that has tiny holes in it
5. the geological principle that uses the same geological process as before
7. breaks down rocks at earth's surface
10. chemically breaks down rocks
11. hard rock underneath the soil
13. method to leave crops in to hold soil in place
14. soil that is equally made up of clay, silt, and sand
15. grinding away rock by ice and water
16. method of farming in which farmers keep switching crops to keep soil fertile
22. layer that is made of mostly clay and other particles
24. chemical change when oxygen and other substances combine
25. great plains area in the 1930's when wind caused soil loss
26. measure of how the soil supports the plants