50 Ways - 3. Credit Other Nitrogen Sources

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50 Ways Farmers Can Protect Their Groundwater

Nitrogen

1. Set realistic yield goals
2. Test the soil
3. Credit other nitrogen sources
4. Apply nitrogen in the spring
5. Use nitrification inhibitors when effective

Scouting

6. Scout fields

Insecticides

7. Know the economic thresholds for insects
8. Consider insect-resistant crop varieties
9. Spot-treat insect infestations when possible
10. Know how tillage affects insects
11. Know how crop rotation affects insects
12. Adjust planting & harvesting dates to control insects
13. Conserve beneficial insects
14. Consider using biological insecticides

Herbicides

15. Know the economic thresholds for weeds
16. Fine-tune your weed program to reduce rates
17. Manage crops to compete aggressively with weeds
18. Don't increase herbicide rates with conservation tillage
19. Band herbicides and cultivate
20. Control weeds with cover crops

Pesticide Selection

21. Determine the organic-matter of your soil
22. Determine your soil's potential for leaching
23. Determine your pesticide's potential for leaching
24. Determine the soil-pesticide interaction rating
25. Consider other critical pesticide qualities

Pesticide application

26. Select the proper nozzle tips
27. Calibrate your sprayer
28. Consider direct injection
29. SPrevent backsiphoning

Pesticide disposal and storage

30. Rinse chemical containers thoroughly
31. Dispose of rinsed containers safely
32. Dispose of excess chemicals safely
33. Store agrichemicals safely
34. Prevent and clean up chemical spills
35. Construct a rinse pad

Site conditions, wells, and septic systems

36. Know your well site conditions
37. Locate your well away from contamination sources
38. Make sure your well is constructed properly
39. Seal abandoned wells
40. Make sure your septic system operates correctly

Water testing & treatment

41. Test your water routinely
42. Test your water for coliform bacteria & nitrate
43. Test you water for pesticides
44. Know the signs of contaminants in drinking water
45. Select effective water-treatment methods

46. Store livestock waste properly
47. Have old, underground fuel storage tanks removed
48. Dispose of other hazardous waste safely
49. Take precautions when irrigating
50. Take precautions when chemigating

3. Credit Other Nitrogen Sources
	Recommended nitrogen application rates should be adjusted to account for nitrogen supplied by previous legume crops, manure, other organic wastes, or residual soil nitrate. If you do not credit other sources of N, you may end up applying more nitrogen than is agronomically necessary or environmentally wise. Charts are available to estimate the amount of nitrogen supplied by legume crops during the previous year, as well as the amount of nitrogen and other nutrients in manure.
	However, the most accurate way to gauge the nutrient content of manure is to have a laboratory analyze samples for your specific farm.
	Based on research at the Northern Illinois Research Center, Illinois agronomists also suggest that for each week of delay in planting after the optimum date for the area, you can reduce the nitrogen rate 20 pounds per acre. The minimum rate would be 80 to 90 pounds per acre for very late planting in a corn-soybean cropping system.