Across
- 4. the layer of soil that differs in color and texture
- 6. a heavier contour line than others
- 11. loose layer of dead plant
- 12. splits rock when water seeps into cracks and freezes
- 14. breaks down rock through chemical changes
- 15. a method that uses old crops to help the soil for new
- 18. a line on a topographic map that connects points
- 20. mass of grass roots and soil
- 22. dark material in soil
- 25. grinding of rock by other rock particles carried by, water, ice, or wind
- 27. same geological process that is used today was used back then
- 29. solid layer of rock beneath soil
- 30. planting of different crops each year
Down
- 1. mixture of clay, humus, and other materials
- 2. processes that break down rock at Earth's surface, chemical and physical
- 3. shows the surface of an area
- 5. characteristic of a material that is full of tiny, connected air spaces
- 7. how we'll soil effects plant growth
- 8. wind erosion caused soil loss
- 9. difference in elevation from one contour line to the other
- 10. rock is physically broken into smaller pieces
- 13. soil organism that breaks down organisms
- 16. management of soil to protect destruction
- 17. a chemical change in which a substance combines with oxygen
- 19. plowing along the curves
- 21. something in the environment humans use
- 23. loose, wheathered, material on Earth's surface, plants can grow
- 24. water, ice, and wind carry wheat here'd rock and soil
- 26. layer of soil beneath the top soil
- 28. rich, fertile soil that is made up of about equal parts of clay, sand, and silt