Integrated Pest Management

While most plants and wildlife co-exist peacefully within Seattle's parks and open spaces, these urban habitats also include non-native pest species which negatively impact native species. Pests can be insects, plant diseases, invasive weeds, animals or birds. They disrupt the natural ecology of a habitat and landscape, creating an unhealthy environment for plants and sometimes for humans and pets.  

Since the late 1970s Seattle Parks and Recreation has used a process called Integrated Pest Management (IPM) to maintain healthy landscapes. IPM is a comprehensive strategy which prioritizes preventative non-chemical methods to reduce pests such as thoughtful plant selection, using mulch to reduce weeds and build soil health, and hand weeding and other non-chemical techniques. In IPM, pesticides are used sparingly as a last resort in targeted applications by trained professionals.  

"Bee City USA" logo

History of IPM

In 1999, the City of Seattle implemented a Pesticide Reduction Strategy to eliminate the use of the most potentially hazardous herbicides and insecticides, and to achieve a 30 percent reduction in overall pesticide use. Starting in 2001, Seattle Parks and Recreation began maintaining 22 pesticide-free parks (~50 acres), and currently maintains over 250 areas - including playgrounds, picnic shelters, community gardens, and turf fields - without pesticides. In 2015 Seattle became a "Bee City, U.S.A.," institutionalizing the commitment to collaborate with the community on establishing and maintaining healthy pollinator habitats within Seattle.

IPM at Seattle Parks and Recreation

Seattle Parks manages over 6,400 acres of parks and open space, nearly 12% of the city's land. These public spaces provide recreation opportunities for people and habitat for a variety of urban wildlife. 

IPM has been practiced by SPR for over 40 years and is our standard operating procedure in natural areas, neighborhood parks, specialty gardens, golf courses, and greenhouses. An IPM program begins with park design and continued attention to plant care and culture, as healthy plants resist pests. 

If a pest concern is identified, SPR staff use cultural, mechanical, biological and (if needed) chemical control methods. For example, cultural could mean planting the right plant in the right place, mechanical might mean hand-weeding, biological could be insect predators or bacterial products for mosquito control, and chemical might be a synthetic or naturally derived herbicide.

An IPM program considers the anticipation of potential pest problems to be the most important tool in pest management. Staff are trained and knowledgeable landscape maintenance professionals who understand the plants cultural needs and the potential for pest impacts and monitor landscape assets continuously in their daily work. Each park facility is unique, and staff evaluate their IPM strategies the over time and make adjustments as needed for long-term successful pest management.

Horticultural and grounds maintenance staff share responsibility for managing pest problems. Staff who apply pesticides are required to have a Washington State Public Pesticide Operator's license and attend continuing education classes in IPM on an annual basis to update their skills and knowledge in pest management.

The department also employs an IPM Coordinator who monitors overall programs, and insures that regulatory requirements are met, including tracking pesticide use. This coordinator works with staff to research and develop new pest management strategies, especially regarding alternatives to pesticide use. The Coordinator also sits on the City of Seattle's Interdepartmental IPM committee, which reviews programs annually and makes adjustments to procedures and protocols.