The Edmonds Parks Department (Parks) manages a wide variety of landscapes, from highly managed garden beds to natural forested areas - and everything in between. Using an IPM approach, Park staff are able to balance the need to keep these areas attractive and safe with the staff and resources they have available.
Park staff have been using an Integrated Pest Management (IPM) approach to reduce pesticide use for the past 30 years. Since 2008, the Parks department has reduced the amount of Glyphosate (e.g. Roundup®) – our most commonly used herbicide - by more than 60%, and applications of other herbicides have been greatly reduced or completely eliminated in some cases. Now, many areas in the Edmonds Parks system are managed and maintained as pesticide free.
With a few exceptions, Parks has transitioned to using Avenger®, a citrus-based, nontoxic herbicide that is completely safe for people, pets, and wildlife. Avenger dissipates and turns into C02 within 2-3 hours after application, and is registered as safe for organic gardening.
IPM Practices in Edmonds Parks
Park staff are responsible for implementing IPM actions. Our IPM approach pays particular attention to landscape/turf planning and maintenance, vigilant monitoring and identification of pests, an understanding of pest life cycles, and proper plant maintenance. It is a proactive approach which strives to avoid pest problems.
Park employees monitor conditions on a weekly maintenance schedule. When pest problems increase beyond a tolerable level, they employ several management strategies to reduce specific problems that reduce or eliminate the need for broad-spectrum pesticides, including mechanical, cultural, and biological control methods.
Most common methods of pest control in Edmonds City Parks
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Plant appropriate vegetation including disease-resistant plant varieties
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Maintain healthy groundcovers, shrubs, and trees through proper maintenance
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Prune shrubs and trees to increase air circulation and remove diseased or dead branches
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Maintain proper turf heights and use grass cycling (leave clippings on turf) to shade out weeds
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Bark mulch shrub areas and tree wells to retain moisture, reduce weeds, and protect vegetation
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Physically remove pests using hand labor, implements, and power equipment
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Use biological controls (e.g. ladybugs and praying mantis for aphid control)

Pesticides
Except in cases of imminent threat to public safety, Parks has nearly eliminated the use of synthetic (i.e. toxic) insecticides, opting instead for biological or mechanical control methods as a first line of defense. For example, Park staff controls small outbreaks of aphids by manually removing affected plant parts to keep the pests from spreading. With few exceptions (e.g. wasp nest, large insect outbreaks) only organic insecticides such as soaps and natural oils are used, and only as a last resort.
Although utmost care is taken to avoid weed problems or control weeds using mechanical methods, herbicides are used on some occasions when mechanical control is not practicable. This may occur when large areas of weeds have become deeply established, when weeds pose a safety hazard (e.g. trip hazard on baseball infields), or other situations when biological or mechanical weed control is not practicable. In some cases, an herbicide may be used to treat the problem initially, with subsequent treatments using only mechanical or biological techniques.
When pesticides are used, they are applied using strict protocols and best practices to protect people, pets, and the environment including:
- Target the right time in the pests’ life cycle to ensure minimal chemical use.
- Applying chemical only to target pest (i.e. spot application).
- Apply chemical during periods of dry weather to prevent runoff and need to reapply.
- Notification flags placed following application to alert the public that a treatment has occurred.
Pesticides are applied by Park staff that have been trained, licensed, and certified through the Washington State Department of Agriculture (WSDA). Training includes requirements for safe practices, knowledge of and adherence to labeling instructions, compliance with state laws, and record keeping. Licenses are renewed annually with a total of 40 educational credits to be acquired within a five year period for recertification. These requirements ensure that staff are qualified to assess, recommend, and implement IPM actions in a safe and effective manner.