University of Washington, Bothell
OP-9: Landscape Management

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A signature element of our campus Organic Land Care program is the near complete elimination of pesticides, herbicides, and synthetic fertilizers since 2006. This practice extends to every square foot of the campus landscape, including our 58-acre floodplain wetland restoration site. (Note: During the past 15+ years we have had 2 noxious weed infestations that, with guidance from the King County Noxious Weed Program, we determined warranted targeted application of Rodeo, a glyphosate-based herbicide. The 1/2-acre Japanese knotweed infestation has since been eradicated and our extensive purple loosestrife infestation has been severely reduced and is now being managed through hand removal and biocontrol insects.) Our commitment to eliminating pesticides and herbicides is motivated in large part by the desire to keep poisons out of our public spaces and create a healthy outdoor environment for our campus community to interact with and enjoy. However, we recognize the benefits go well beyond that by fostering a healthy soil food web, beneficial insect and wildlife populations, as well as improved water quality and enhanced function of our green infrastructure.

Our Organic Land Care ethic extends to plant stewardship, water use, and landscape waste as well. The foundation of much of our landscape plantings are native species, along with a large diversity of regionally appropriate pollinator plantings and the integration of edible plants throughout the campus landscape with food being the primary focus of the Campus Farm, Food Forest, and Orchards. Planting regionally adapted plant material and fostering healthy soil, along with robust mulching practices, coupled with a weather-based centrally controlled irrigation system and extensive drip irrigation, allows us to use water extremely efficiently. These landscape practices and the green storm water infrastructure provided by our 58-acre restored campus wetland and numerous rain gardens in the built environment contributed to our Salmon Safe certification in 2008. In addition, well over 90% of our landscape waste stays on site to be composted or chipped and returned to our gardens or remains in the landscape as leaf litter and large woody debris.

Our campus IPM program encompasses both buildings and landscape and like all IPM programs strives to reduce or eliminate the need for toxic pest control products through monitoring, prevention, habitat manipulation, non-chemical strategies, tolerance, and if needed, the selection of least toxic chemical controls.  Our pest control contractor, Stop Bugging Me Pest Control, is Green Pro certified and provides pest control for all campus buildings and assists with stinging insect mitigation in the landscape.  A single technician is assigned to our campus and they work closely with our Grounds Supervisor/IPM Coordinator on all pest issues, meeting during each site visit, and is contractually obligated to follow the campus IPM Policy.

Beyond a reliance on native and drought tolerant species, a general commitment to wild-type pollinator supporting plants and plant communities, and ongoing natural area restoration and protection, we actively provide educational opportunities for the campus community and the greater regional community on all aspects surrounding our practices related to sound and sustainable plant stewardship.  In addition, we aim to empower the community to deepen their direct relationship with plants, and the natural world for that matter, through the offerings provided by our Campus Farm, Food Forest, Medicinal Herb Garden and other edible and “usable” landscapes features.

Campus is situated on an east facing slope with a 58-acre floodplain wetland, containing the lowest reach of North Creek, at its base.  Before construction of the campus built environment even began, major efforts were underway to restore functionality to the campus wetland and reroute North Creek to its historic path through the site.  The entirely of the campus’ storm water needs is being met by the green infrastructure provided by the campus wetland. Campus green infrastructure has recently extended in significant ways to the campus built environment with the last 4 capital building projects (2 academic buildings, a student center, and a parking garage) all having rain gardens designed into their surrounding landscapes to capture, infiltrate and discharge all excess storm water into the campus wetland.  As a general rule landscapes are designed to be drought tolerant, annual plantings are restricted to display pots, less than 25% of turf areas are irrigated, and mulching and soil building are the norm.  Drip irrigation has been retrofitted in many of the campus beds and plantings related to new construction are primarily utilizing temporary irrigation of drip.  The campus irrigation system is run by a weather station informed central control system.

We start with the acknowledgement that there is no waste in a natural system, only the recycling and reassignment of resources.  Furthermore, it is our aspiration, albeit, an admittedly impractical one due to the realities of new construction, plant, seed, topsoil, mulch, and fertilizer procurement, that no outside inputs be required to see the campus landscape into the future.  We do, however, come close in our day to day landscape management.  Our only fertilizer use is on our irrigated turf areas (twice yearly), new plantings, display pots, and food production areas.  Fertilizer is sourced locally.  All large woody debris from tree removals and storm related failures is kept in the campus landscape, all woody pruning material is chipped and used as mulch.  The vast majority of green waste is composted on site or taken to a commercial composting facility with only regulated noxious weeds ending up in the landfill.  All lawns are mulch mowed.  Plants are grown from seed, cutting, and division regularly.  Procured plants are sourced from local growers and patented varieties are avoided.  Materials such as lumber, concrete block, stone, cobble, pavers etc. are salvaged, stockpiled and repurposed when needed.

We ensure that all designed beds are planted in such a way that provide as close to, or that even exceed, 100% vegetation cover, in varying layers, heights, and structures. Open hardscaped areas such as plazas, patios, and promenades where planting areas do not exist are vegetated using large display pots filled with trees, shrubs and perennials. Large deciduous trees are planted on the south sides of building to provide shade in the summer and to allow natural light into the building in the winter. Five Tupelo trees were added to the main lawn in the core of campus this past year to provide a shady place to sit for many years to come as well as address the heat island effect in this predominately hardscapes area of campus.

All mature trees on campus are tagged and inventoried (spreadsheet) along with structural characteristics such as DBH (2005, 2017) and height, crown width, crown density (2017). Level 2 Basic Risk Assessments were performed on each tree in 2005 and again in 2019 by a certified arborist. Level 1 Limited Visual Assessments have been performed every year since 2010 by a certified arborist, with the exception of 2019 in which an enhanced assessment was performed. Finding of these annual tree assessments allow us to take a proactive approach to fostering tree and stand health as well as target our risk mitigation in order to conserve as many mature trees as possible for as long as possible. Any trees that need to be removed are snagged at 20-30 feet and all large woody debris and woodchips remain on site.