Regulatory Pest Control
Pest Control Methods
An effective regulatory pest control program considers a variety of tactics to control pests. The primary method to prevent the introduction of a pest into an area is through the use of quarantines. However, once a pest has been introduced into an area, other tactics take importance. Pesticide use is one of these tactics.
Selecting a Pesticide
When a pest is newly introduced into an area and not widely distributed, the use of pesticides is generally considered to be a sound practice. There are a number of factors that must be considered before deciding which pesticide to apply and the method of application. This would include but is not limited to the following:
(Adapted from Jenkins, Randall and McCumber, 2006)
- What are the vulnerable life stages of the pest?
- Is the host species in a suitable location to apply pesticides?
- What method of applying a pesticide will prove to be most effective?
- What pesticide formulation is best suited to the situation?
- What is the mode of action of the pesticide being considered?
- Where is and how large is the treatment site?
- What effect will the pesticide have on the target and nontarget organisms?
Other Methods of Control
Biological Controls are sometimes introduced into an area where an exotic pest is wreaking havoc. This involves some risk, however. The biological control introduced into an area has the potential to disrupt the natural ecosystem. Therefore, a lot of research is conducted prior to introducing a biological agent into an area to control an exotic pest.
Habitat or Food Source Elimination is sometimes effective at controlling an exotic pest when the pest is confined within a limited geographic area. For example, if a nursery shipment contains an exotic pest, one might choose to destroy the host plants and monitor any potential host plants for a period of time afterwards.
Buffer Zone is created. When a pest infestation has expanded to the point that is not feasible to try to completely eliminate the pest’s food or habitat, one might consider creating a buffer zone around the infested area. This involves eradicating the pest’s food or habitat within the buffer zone to prevent the further spread of the pest. Once this is done, one can then refocus one’s attention on eliminating the pest within the contained zone.
Many times, regulatory pest control efforts are under public scrutiny. It is best if the public is kept informed as to the scope of the pest problem, measures being utilized to control the pest and the risks versus benefits of any pesticides being utilized to control the pest.
Groundwater Protection
It is important that those managing a regulatory pest control program be concerned with protecting surface water and groundwater resources. A pesticide that has not been absorbed by plants, adsorbed by the soil, volatilized off as a gas or broken down by natural degradation processes may leach into groundwater or surface water resources.
A number of practices can and should be followed to prevent groundwater or surface water resources from being contaminated with pesticides. These are addressed below.
- Keep pesticide use to a minimum by implementing integrated pest management practices.
- When locating well, mix/load sites and equipment wash areas, factor in a site’s geologic characteristics and any groundwater vulnerabilities that might exist. Be aware of the water table depth and how fast water moves through the soil and into the groundwater.
- Select pesticides that are less likely to runoff into surface waters or leach into the groundwater.
- Keep in mind that pesticides that are very water soluble and do not bind easily to the soil are very prone to leaching.
- Read pesticides labels carefully and do not hesitate to call your county extension agent to select the best possible pesticide for your situation.
- Follow the label instructions when applying a pesticide – it’s the law.
- Carefully calibrate spray equipment to prevent over or under applying a pesticide.
- Carefully measure a pesticide concentrate before adding it to a spray tank.
- Avoid back-siphoning by making sure the hose-end stays above the water level.
- Use an anti-backflow device when siphoning water from a well, pond or stream.
- Avoid spraying a pesticide just before an expected heavy rain.
- Load and Mix pesticides on an approved impervious mix/load pad where spills can be contained and cleaned up.
- Dispose of pesticide containers and waste properly in accordance with local, state and federal laws.
- Store pesticides is a safe manner and away from water supplies.
Protecting Non-Target Species
Apply integrated pest management practices to minimize the use of pesticides and their impact upon non-target species. It is especially important that one take precautions to see that bees are not impacted.
Do not treat near beehives and consider covering or moving beehives found in an area that is going to be sprayed with pesticides. When treating an area where bees are present, it is best for the bees if one selects the least hazardous pesticide formulation for the bees. With this in mind, be aware that dusts are more hazardous to bees than sprays. Wettable powders are more hazardous than emulsifiable concentrates or water-soluble formulations. Microencapsulated pesticides are extremely toxic to bees and granular insecticides are generally the least hazardous to bees.
To avoid injuring bees, remove flower blooms by mowing before spraying a site. Minimize pesticide spray drift by adding an adjuvant, selecting nozzles to produce a coarser spray, and/or avoiding spraying when it is windy. Keep in mind that evening pesticide applications are less hazardous to bees than early morning applications which are less hazardous than midday applications.
Pesticides can enter surface waters via runoff or drift and may be toxic to fish, sometimes by changing the pH of the water. Birds can also be injured by pesticides if they drink contaminated water, eat pesticide granules, treated baits or seed, feed on pesticide-contaminated prey or are sprayed with pesticides.
Endangered or Threatened Species
As required by the Endangered Species Act, every pesticide that poses a threat to an endangered or threatened species or its habitat must have a warning statement on the label. The label is the law, so if there are any instructions on how to safeguard an endangered species when applying a pesticide, they must be followed.
Pesticide Resistance
Repeated applications of the same pesticide or of pesticides having a similar mode of action will select for pests that have resistance to these pesticides. With this in mind, it is wise to employ practices that will minimize the chance of repeated use of a single pesticide or pesticides having a similar mode of action.
A program that is designed to prevent or slow the development of pesticide resistance in a pest population will include the following:
- Use integrated pest management practices which use a combination of cultural, mechanical, biological and chemical control practices in the management of pests.
- Rotate chemicals so that pesticides from different chemical families with different modes of action are being used.
- Use pesticides only when required, and only as much as is necessary to maintain control.
Drift Management
It is good practice to inform adjacent landowners, neighbors and beekeepers in advance of a large-scale pesticide application. An effective drift management program should contain the following:
- A map of the area where pesticide applications occur.
- A list of pesticide-sensitive sites located near an application area.
- A pesticide label and mandated restrictions that address setback distances from sensitive areas.
- Be ready to supply pesticide application information to persons living in sensitive areas.
A drift management plan can be used by private and commercial applicators as a means of communication with the public and to minimize the chance of off-target pesticide drift onto non-target sites.
Conclusion
An effective regulatory pest control program will consider using a variety of pest management options, including the use of pesticides, to control an exotic pest that has been introduced into an area.