how to Selecting and Using Pesticides

Criteria for choosing a pesticide include:

  1. Safety is top priority
    Questions to ask include what is the toxicity level of the pesticide (measured by LD50–the higher the LD50 number, the less toxic); how mobile is the pesticide and in what fashion can it be distributed (through air, soil, water, etc.); what is the residual life of the pesticide; and what are the environmental hazards listed on the label?
  2. Species specificity
    This is especially important to look for before using toxic chemicals since certain pesticides only affect the target animals or plants. Try to avoid getting broad spectrum pesticides that have potential to kill or harm many beneficial species along with the pest. If such a pesticide is the only option, try doing spot treatments to reduce the likelihood of affecting non-target organisms.
  3. Effectiveness
    For pesticides, it is a bit difficult to measure effectiveness because it can vary depending on where the chemicals are being applied. In a lab, for instance, a chemical may kill a large percentage of the target pest because it is a controlled environment, but in a real life situation, the number may be much smaller due to other factors such as killing off natural enemies, temperature changes, etc. Evaluating uses of a considered pesticide in similar situations as that of your school may help in estimating the kind of effect it will have.
  4. Endurance
    An animal or plant’s endurance to the effects of a pesticide may vary. Watch for success in pest control: if it at first seems to work well but then later populations grow despite continued use, there may be some built up resistance.
  5. Pesticides vary in their speeds of interaction
    Choosing a pesticide should be determined based on circumstances. If it is an emergency, a shorter lived, fast acting and more acutely toxic material (such as organophosphate for cockroaches) may be necessary. But a longer lasting, slow acting and less toxic material (such as boric acid) may be better for chronic pest problems.
  6. Cost
    This is always a consideration when deciding what chemicals to use. Determination of cost often is done by measuring dollars per volume-some new materials that are effective in lower doses may be more expensive than older pesticides that need larger amounts to do the job. A small container of more concentrated material may seem more expensive, but may be as effective as three times that much in another kind of pesticide.
  7. Once a pesticide is selected, notify
    Give notification to personnel, students, and parents about what pesticide will be (or has been) used and where it is going to be (or has been) applied so they are aware of any possible exposure. Ideally applications should be done when buildings are unoccupied, but regardless, it is best to give advanced notice that an application is scheduled so that everyone can take appropriate steps to ensure the safety of those involved.

Using Pesticides

  1. Registration 
    Make sure that the product is registered for use in Nebraska and know the laws regarding its use. Search for registered products in Nebraska.
  2. Read the Pesticide Label
    Follow its directions for use, registrations, storage, and disposal to the letter. Signal words on labels indicate the toxicity levels:
    • DANGER-a taste to a teaspoon taken by mouth could kill an average-sized adult.
    • WARNING-a teaspoonful to an ounce taken by mouth could kill an average-sized adult.
    • CAUTION-an ounce to over a pint taken by mouth could kill an average-sized adult.
  3. Secure (if required) written recommendations
    Obtain these from a licensed pest control advisor for use of the pesticide.
  4. Personal Protective Equipment
    Make sure that all safety equipment, such as gloves, goggles, respirator, hat, etc. are available and worn when the pesticide is used.
  5. Pesticide applicators should be licensed
    Commercial operators must have a license to apply pesticides on school grounds and be able to handle all equipment needed for the application. Search for licensed applicators in Nebraska.
  6. Equipment
    Make sure it is correctly calibrated and appropriate for the job at hand.
  7. Spot treat 
    This will keep material confined to the area requiring treatment.
  8. MSDS Sheets should be available
  9. Keep records
    What pesticide was used and for what? How much was used? Be sure to list all pertinent information about the treatment for future reference about what was done.
  10. Monitor for pests after the application
    Post-treatment monitoring can help determine the method’s success.
  11. Compile Emergency Contact list
  12. Disposal
    Do not put pesticides down toilets, sinks, or other drains or gutters. Follow the manufacturer’s directions for proper disposal.

Why are micronutrients important for plant growth?

  • Due to higher yields, commodity prices and crop input costs, growers are reviewing all potential barriers to top grain production, including micronutrient deficiencies.
  • In the major crops and production areas of North America, the micronutrients most often supplied by fertilization include zinc, manganese, boron and iron.
  • Micronutrient deficiencies can be detected by visual symptoms on crops and by testing soils and plant tissues.
  • The most reliable micronutrient soil tests are for zinc, boron, copper, and manganese. Though adequate, these tests are not as precise as those for soil pH, potassium and phosphorus.
  • Plant tissue analysis is more reliable than soil testing for identifying many micronutrient problems, and can also supplement soil test information.
  • Most often, micronutrients are soil-applied in a band at planting, or foliar-applied, as these methods allow lower use rates of sometimes expensive materials.

Micronutrients are essential elements that are used by plants in small quantities. For most micronutrients, crop uptake is less than one pound per acre. In spite of this low requirement, critical plant functions are limited if micronutrients are unavailable, resulting in plant abnormalities, reduced growth and lower yield. In such cases, expensive, high requirement crop inputs such as nitrogen and water may be wasted. Because of higher yields, higher commodity prices and higher costs of crop inputs, growers are reviewing all potential barriers to top grain production, including micronutrient deficiencies. This Crop Insights will discuss general micronutrient requirements, deficiency symptoms, soil and plant sampling, and fertilization practices. Future Crop Insights articles will discuss specific crops, their micronutrient or secondary nutrient requirements and management considerations.