50 Ways - 14. Consider Using Biological Insecticides

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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

14. Consider Using Biological Insecticides
	Biological insecticides are actual living organisms or the toxins produced by them. Examples include viruses, bacteria, fungi, and nematodes. The chief benefit of using biological, or microbial, insecticides is their low toxicity to humans and nontarget insects. Some of these insecticides are so selective that they affect only one part of the life cycle of the insect, such as the caterpillar (larva) stage of moths and butterflies. The low toxicity also means less risk to groundwater and surface water.
	But there are drawbacks. Biological insecticides do not have as long of a shelf life as conventional pesticides, so proper storage is critical. In addition, certain microbial pesticides can lose their effectiveness rapidly if exposed to heat and ultraviolet radiation, or when they dry out. For this reason, proper timing and application procedures are extremely important.
	When looking for biological insecticides, keep a few points in mind. Biological insecticides probably will not control heavy pest populations, but they can control moderate populations of newly hatched worms. Biological insecticides must be ingested by the larvae, which will stop feeding within a few hours and die within two to five days. Also, most currently available biological insecticides are highly selective for the control of certain caterpillars.
	In many states, some of the biological insecticides available for use in field crops include Biobit, Dipel, Full-Bac, and Javelin. The common denominator among all of these products is that they contain the active ingredient Bacillus thuringiensis, or Bt, a bacterium.
	The different biological insecticides may be formulated as dry or wettable granules, emulsifiable suspensions, or flowable concentrates. Crops for which some or all of these insecticides are registered include alfalfa, corn, small grains, sorghum, and soybeans.
	The insects listed on some or all of the labels are alfalfa caterpillars, armyworms, corn earworms, cutworms, European corn borers, fall armyworms, green cloverworms, and webworms. As with synthetic chemical insecticides, it is extremely important to read the label of biological insecticides. The different products vary in terms of application rates, methods, timing, and placement.
	Another avenue for using biological insecticide is Bt corn. Advances in genetic engineering now allow the transfer of genes from one species to another. By implanting the bacterium, which is not toxic to people or animals, directly into the genetic make up of the corn, the crop is resistant to first-generation corn borers.