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Dec
12

Pest management

Beginning in 1999, King County has required the use of integrated pest management (IPM), a comprehensive approach to pest management. To control invasive and non-native plant and animal species, IPM stresses the prevention of pest problems through a wide range of techniques with the use of chemical controls as a last resort. King County’s IPM program evaluates pest control strategies and encourages non-chemical controls when effective and practical.

The IPM process categorizes pesticides as either Tier 3, lowest hazard; Tier 2, moderate hazard; or Tier 1; highest hazard. If the pest is a state regulated noxious weed and its control or eradication requires the use of specific chemical pesticides, the staff may submit a Tier 1 Product Exception Request to the IPM program administrator.

Policy and Goals:

As stated in King County's Sustainable Purchasing Executive Policy (CON 7-22-EP),

  • Use integrated pest management practices

As stated in the IPM Executive Policy and Tri-County IPM Policy, this policy strives to:

  • Reduce the potential impact of pesticide use on listed species, including the Puget Sound Chinook salmon and the bull trout
  • Improve the public health and the environment in King County
  • Better manage the long-term effects of vegetation and pest problems in King County

Example - Natural Vegetation Management with Goats

King County Metro Transit has used goats to manage blackberry bushes and other weeds at several park and rides. These various sites have been difficult to maintain due to steep hillsides and uneven ground. The goats are a more efficient way to control the weeds than crews of human workers, present less risk of injury to the human staff, and eliminate the need for chemical maintenance. This service is needed twice a year to deter new plant growth. King County was so pleased with the results, it expanded the area serviced by these animals and continues to use them as needed. 

Best Practices

  • Choose and properly maintain the appropriate plants for the area.
  • Document and identify potential pests and determine a tolerane threshold.
  • Put up phsyical barriers or remove the pest by hand.
  • Obtain a permit from WSDA, USDA, EPA, etc. or a biological management activity, which includes using animals, insects of competing vegetation to control the pest.
  • Use chemical pesticides as the last resort and don’t over fertilize.

Quick Tips

Choose

  • integrated pest management
  • biological controls
  • tier 3 pesticides
  • natural vegetation management
  • require IPM in service contracts
  • natural organic or slow-release fertilizer products that feed plants longer and are less likely to wash off into streams and lakes
  • spot spray

Avoid

  • chemical use
  • tier 1 pesticides
  • "weed & feed" fertilizer/herbicide mixtures

End of Life

  • find an appropriate user for surplus through the Industrial Materials Exchange
  • recycle with King County’s Local Hazardous Waste Management Program

An EPA checkmark indicates a certification or standard is recommended by the U.S. Environmental Protection Agency (EPA).

Ranking by Tiers as Classified by King County and the City of Seattle Tier Definitions

Tier 1: Highest concern, highest priority for phase out

Any of the following are true. All ingredients should be identified so that they can be screened using these tests.

  • Products in Hazard Category I: Signal word DANGER
  • Restricted use pesticides (except aquatic herbicides)
  • Products that cannot be disposed of because of dioxin contamination
  • Products with active ingredient on the state list of acutely dangerous wastes
  • Products with known, likely, or probable carcinogens as active ingredients
  • Products with reproductive toxicants as active ingredients (CA Prop 65 list)
  • Products with known or probable endocrine disruptors as active ingredients
  • Products labeled as highly toxic or extremely toxic to birds, aquatic species, bees, or wildlife.
  • Products with active ingredients with soil half-lives greater than 100 days
  • Products with active ingredients with mobility ratings high or very high or with specific label warnings about groundwater hazard.

Tier 2: Moderate concern, second priority

All products not specifically assigned to tier 1 or tier 3.

Tier 3: Lowest concern

All of the following are true. All ingredients should be identified so that they can be screened using these tests.

  • Product contains no possible or probable carcinogens
  • Product contains no reproductive toxicants (CA Prop 65 list)
  • Product contains no ingredients listed by Illinois EPA as known, probable, or suspect endocrine disruptors
  • Active ingredient has soil half-life of 30 days or less (exception for minerals)
  • Active ingredient has extremely low or very low mobility in soils. Product is not labeled as toxic to fish, birds, bees, wildlife, or domestic animals.

Tier 4: Insufficient information available

Product registration or label not found or key data not located for active ingredient. Cannot assign to another tier.
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