From tree to forest: resilience in the face of climate change

Resilience according to the IPCC: The ability of a system and its component parts to anticipate, absorb, accommodate, or recover from the effects of a hazardous event in a timely and efficient manner, including through ensuring the preservation, restoration, or improvement of its essential basic structures and functions.


There is a tree a few yards away from my house that stands proud above the rooftops, powerlines, and fragmented urban life below. Every morning I look forward to hearing the tree come alive with a symphony of crows, sparrows, starlings, and steller’s jays collectively singing in what is known as a dawn chorus. I’ve grown increasingly fond of this immense giant, a western redcedar (Thuji plicata) and its inhabitants during this time of solitude. The tree’s important presence in an urban ecosystem that has been manipulated by the pace and patterns of development and growth serves as a reminder that survival, adaptation, and even resilience are possible in an ever-changing urban environment. 

Looking through my binoculars at a European Starling (Sturnus vulgaris) singing in “the tree”, a western redcedar, that has captured my attention. Starlings were intentionally released from Europe to America by a group of Shakespeare enthusiasts who wanted to introduce all the animals mentioned in his work. Starlings are ubiquitous throughout the urban environment and often forage on lawns, golf courses, gardens, and enjoy human food scraps. (Photo credit: Marlena Skrobe)

 

The Puget Sound region, where the tree and I live today, has a population of around 4.2 million people. It does not look like the Puget Sound did 80 years ago, or the forests of the Puget Sound that flourished before non-Native settlement hundreds of years ago. We will never be able to restore the environment to what was, but in the face of evolving social, economic, and ecological disturbances exacerbated by climate change we can improve our collective stewardship and ultimately the resilience of our critical urban ecosystems, including our urban forests

View of Elliot Bay and the Cascade Mountains from Hamilton Viewpoint, previously called Duwamish Head Park, a public park in West Seattle. (Photo credit: Marlena Skrobe)

 

For Seattle, also known as The Emerald City, trees play vital environmental, economic, social, and cultural roles. The western redcedar often the unofficial symbol of the Pacific Northwest, is so deeply rooted in the lives of Pacific Northwest native peoples it is often referred to as the “tree of life.” Tulalip tribal youth, for example, participate in cedar harvests organized by Tulalip Forestry to learn how to weave traditional baskets, headbands, and different items of cultural importance. However, western redcedars, like so many other important trees and native plants, have suffered die-offs in the past few years, often from drought stress and pests that are becoming all more common with the shifting climate

As projected climate changes become a reality, how do we move forward to create more resilient urban ecosystems and urban forests vital to our health and wellbeing? Urban areas in particular pose significant challenges to ecosystems’ overall health and functionality. Urbanization transforms the natural landscape by fragmenting habitats, decreasing biodiversity, disrupting hydrological systems, altering the local climate, among many other pressures that influence the functionality of the ecosystem and the services it provides for human beings. Resilience in an urban environment, in particular, is a complex, multifaceted challenge that not only requires interdisciplinary collaboration in both research and practice to create innovative sustainability planning strategies, but collaboration with those who interact with the environment the most – the people who live, breathe, and love the urban landscape around them. People like me, who are currently confined to the bounds of rigid house walls, but have found solace in a tree and all the wildlife connected to it. 

One such instance of collaboration is the Green Seattle Partnership (GSP), a public-private effort between the City of Seattle, Forterra, schools, community partners, and thousands of volunteers who work together in order to create a healthy network of forested parkland throughout the Seattle area. GSP was developed in 2004 as Seattle’s parks faced critical threats that would prove dire unless restoration efforts were undertaken. The GSP’s 20 year strategic plan focuses on restoring and maintaining over 2,500 acres of forested parklands and other natural areas by galvanizing active community stewardship.

Michael Yadrick, plant ecologist of Seattle Parks and Recreation, coordinates and supports many of these GSP restoration projects. These projects include the removal of certain problematic invasive species, planting trees and understory plants, and constant monitoring. Yadrick explains that in addition to short term solutions, GSP has been thinking long term by working to find species that are more drought tolerant to establish and survive better through changing climates. “Last season we intentionally started sourcing plant material like longer lived conifers- seedlings from further south in Oregon’s Willamette Valley and planted them in Seattle’s forests,” says Yadrick. The 10,000 trees, such as Douglas Fir, western redcedar , Western Hemlock, Western White Pine, that were planted are indeed native species to this region, but the southern genotypes were moved north as a way to transition forests in the Puget Sound region to survive warmer, drier conditions. Similar climate-based seed transfer work is being done in British Columbia as a resilience strategy of a broader Climate-Based Genetic Resource Management initiative. 

Mapping the location of monitoring plots within the replanted areas of the Stossel Creek Site. (Photo Courtesy Northwest Natural Resource Group)

 

An hour east of Seattle, The Stossel Creek Site project (which includes 154-acres of land with critical steelhead and salmon habitat) is another example of collaborative adaptive restoration with the hope of improving resiliency of Western Washington forests. The site, whose history is similar to that of many parts of Western Washington, was previously logged and used for commercial forestry. Seattle City Light purchased the land in 2015, and in partnership with Mountains to Sound Greenway Trust, Northwest Natural Resource Group, and Seattle Public Utilities, began restoration efforts to encourage long term ecological functions for water quality with steelhead and salmon in mind. 51 of those acres are being planted with seedlings sourced (with the help of the Seedlot Selection Tool) from areas that have climates similar to the projected future climate of the Stossel Creek area. This includes three different seed sources of Douglas fir, two of western redcedar, species associated with drier Douglas fir ecosystems, such as Shore Pine, Grand Fir, Western White Pine, and Oregon White Oak. Hopefully, increasing tree diversity and planting tree species that are adapted to drier, warmer climates will improve long-term functional stability. 

Dan Hintz, Mountains to Sound Greenway Trust Restoration Projects Manager, explains that in thinking about the future it’s also a balance between implementing short term response actions and long term resilience goals. Activities like watering the trees more, adding mulch to help with tree establishment, removal of certain weeds like blackberry and knotweed to reduce competition, all work towards these short term goals and are easier to monitor for improvement. However, Hintz says, “when you’re talking about forest health, in the year 2050 or 2100, that becomes a lot more difficult.” Hintz recognizes the importance of sharing lessons learned and collaborating with other individuals and organizations in such a nascent area of climate adaptation, which is why NNRG, the Mountains to Sound Greenway Trust, and other partners held a workshop earlier this year with financial support from the Wildlife Conservation Society. 

The Stossel Creek Project and the efforts of Green Seattle Partnership are examples of innovative projects being undertaken with long-term adaptation in mind, but they are also great examples of collaboration – a key ingredient for improving resilience of our forest ecosystems, urban and otherwise. When thinking about resilience it’s important to consider – resilience for whom and by whom? This question is especially important as the future of our ecosystems’ health becomes more complex. As I look to the western redcedar I have a new appreciation of its role in an ever-changing urban environment. The birds singing in its branches may not all be native to the Puget Sound region, but they too are a part of this ever-changing urban environment. The tree may not survive the years to come, but another tree may grow in its place and that is because humans, who are deeply embedded in these changes, are also part of solutions in urban ecosystems and beyond.


The following photo story explores this complexity in Seattle. 

Click on the first photo to start the gallery

Downtown Seattle visible over a canopy of trees from Kerry Park, a small public park on the south slope of Queen Anne Hill in Seattle. According to a 2016 Canopy Cover Study, 28% of Seattle is covered with trees. (Photo credit: Marlena Skrobe)
English Ivy, also known as Common Ivy, in Leschi Park, an 18-acre park named after Chief Leschi of the Nisqually Tribe. The Ivy is visible from Cable Car Trail in a densely vegetated ravine. English Ivy is a rapidly growing, evergreen climbing plant that is invasive to the Pacific Northwest and is on the Washington State official noxious weed list. (Photo credit: Marlena Skrobe)
Invasive Himalayan blackberry, a Class C noxious weed in King County, which means that control is recommended, but not required because it is already so widespread. Himalayan Blackberry outcompetes native vegetation and can prevent the establishment of native trees. (Photo credit: Marlena Skrobe)
A giant sequoia (Sequoiadendron giganteum) stands tall in the Leschi neighborhood of Seattle. (Photo credit: Marlena Skrobe)
A newly planted tree with stakes helping support the tree trunk while its roots develop grows next to an older tree in Seward Park, Seattle. Seward Park is an entire peninsula extending into Lake Washington from southeast Seattle. Part of the park includes the Magnificent Forest, remains of an old-growth forest, characterized by trees that are over 250 years old, multi-layered canopy, and downed logs.
A dying tree amidst a sea of greed in Seward Park. Seattle Parks and Recreation Department’s Tree Maintenance Program is responsible for maintaining the health and safety of trees throughout Seattle’s extensive park system. Tree crews look after trees in the parks and boulevards, which often includes conducting hazard tree reviews from various staff members and citizens. While dead trees may not be the most attractive to look at, they are essential to forest health as they provide habitat, decrease erosion, and cycle nutrients for other plants. (Photo credit: Marlena Skrobe)
A spectacular chestnut tree that has been trimmed to protect communication wires stretching across the paved streets of Meridian neighborhood. American chestnut trees (Castanea dentata) once dominated eastern forests. Mature American chestnuts, giants of the east with trunk diameters over ten feet and a height of more than 100 feet, have been virtually extinct for decades. A pathogenic fungus (Cryphonectria parasitica) from imported Japanese chestnut trees caused the ‘chestnut blight’ in the early 1900s. Human actions resulted in the catastrophic demise of native chestnuts, but efforts between scientists, foresters and countless other collaborators will hopefully revive a new generation of American chestnut trees to withstand future environmental conditions. (Photo credit: Marlena Skrobe)
Eastern cottontail rabbits (Sylvilagus floridanus) are the second type of rabbit that was introduced to Washington by hunting enthusiasts. There are no rabbits native to the Puget Sound region, but the Eastern cottontail and the domestic rabbit, which was introduced to the San Juans, do well in urban environments since they have few predators and plenty of vegetation for consumption. (Photo credit: Marlena Skrobe)
Licton Springs, a sacred site and natural curative resource for Duwamish and Coast Salish tribes of the Puget Sound region. The natural spring fed into Green Lake before it was altered for city infrastructure in the early 1900s. The Urban Native Education Alliance (UNEA) are working to revive the spring’s Native history and designate the site as a historical landmark to protect the spring from further development. (Photo credit: Marlena Skrobe)
View of the Duwamish Waterway from Herring’s House Park, a 15.5 acre park restored as a part of the SuperFund cleanup effort in the first five miles of the river basin. The park is named after the Duwamish village Herrings House, which was originally located on what is now south Harbor Island. The Duwamish estuary was once a meandering river with productive tidal flats, but was sold off after the Treaty of Point Elliott and became a shipyard and industrial area. Current restoration efforts are a collaborative effort between the Duwamish Alive! Coalition, Green Seattle partnership, EarthCorps, and many other stewards. (Photo credit: Marlena Skrobe)
A downed Douglas fir in Schmitz Preserve Park in West Seattle. The park is named after Ferdinand and Emma Schmitz, German immigrants who donated a large portion of the park between 1908 and 1912 in order to preserve the old growth forest for years to come. (Photo credit: Marlena Skrobe)
The rings of Seattle’s largest cottonwood tree, which once stood tall in Madrona Park, but blew down during a storm in January, 2019. (Photo credit: Marlena Skrobe)
An old Maple Tree in Madrona Park that has lost one of its limbs. There are three common maple trees found in the Seattle area, but only the Bigleaf Maple (Acer macrophyllum) and Vine Maple (Acer circinatum) are native. (Photo credit: Marlena Skrobe)
What is left of a sword fern (Polystichum munitum) on the south side of Hatchery Trail in Seward Park. In 2013 park visitors began noticing sword ferns dying off in the area near Hatchery Trail and by July of 2014 90% of sword ferns died in an area the size of ¼ an acre. Unfortunately, that size of the sword fern die-off has grown to almost 20 acres and similar die-offs have been identified in Western Washington and British Columbia. No one knows what is killing the ferns, which are a fundamental aspect of the plant community, but many are worried that similar die-offs elsewhere are going unnoticed. (Photo credit: Marlena Skrobe)
The paved surface of Lake Washington Boulevard South winds through a variety of Maple trees in Leschi Park, Seattle. (Photo credit: Marlena Skrobe)