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3. Farmers can slow the speed of water flowing down the hill by ____.
6. ___ slows the speed of water flowing down a slope
8. Supports plant and animal life and can be polluted
10. planting grasses between rows of other crops
11. the ___ use the nutrients to grow and build their body parts
13. ___ help prevent soil from being washed or blown away
14. the land becomes less able to support the ___ of new crops if a farmer completely removes a crop from the land
16. farmers use chemicals to kill insects that eat ___, but these chemicals can pollute the soil that the ___ need to grow
18. where there are ___, the wind is less likely to blow away topsoil
19. planting different crops on the same land in different years
20. when people dump ___ on the ground, the ___ can also pollute soil
21. the ___ in soil are naturally removed by plants
24. is the addition of harmful materials to soil, air, or water
25. flat shelves that are cut into a hillside

1. wind and erosion were major causes of this event that happened in the 1930s
2. a way to inform people of the value of soil and how to conserve it
4. can be conserved in many different ways
5. soil can be polluted by ___ placed in the ground
7. A mixture of bits of rock and once living parts of plants and animals
9. soil can also be polluted by chemicals used to kill __ and weeds
12. ___ may pass laws to stop the pollution of soil
13. protection of natural resources
15. ___ efforts: recycling, reusing ...
17. protection of natural of natural resources, including soil
22. ___ are normally replaced when plants die, fall to the ground, and decay
23. ___ containing one or more nutrients can be added to soil to replace nutrients