Across
- 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
Down
- 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