Forest Ecosystem Services in the Northwest
Four standard categories of ecosystem services, as popularized by the United Nations Millennium Ecosystem Assessment in 2005.
The Northwest is home to a mosaic of forest ecosystems, from the boreal forests of central Alaska to the dry juniper woodlands east of the Cascade Mountains. Forests provide many ecosystem services to communities across Oregon, Washington, Idaho, and Alaska. Ecosystem services are often grouped into the following four interdependent categories:
- Supporting services are basic natural processes that underpin all other ecosystem services, such as water and nutrient cycling.
- Regulating services are benefits from supporting services that have a more direct impact on human well-being, such as pollination and water filtration.
- Cultural services are nonmaterial benefits to people and communities, such as spiritual connections to the land and recreation.
- Provisioning services are products generated from forests, such as timber and fresh water.
Climate change is impacting Northwest forests and may reduce their ability to provide key ecosystem services. By understanding these changes, we can manage forests to help prepare them for the future. Below, we provide an overview of climate change effects on key forest ecosystem services.
Water Quality and Quantity
Forests help keep our water clean and ensure a consistent water supply for ecosystems and people. Tree roots hold soil in place and prevent the erosion of excess sediment into waterways. The forest canopy catches rainfall, slowing it down so it can soak into the ground instead of quickly running off the surface. Forest soils filter pollutants and nutrients from the water before it enters streams and rivers. Preventing erosion and filtering water are regulating ecosystem services. Water cycling, where trees absorb and release water, is a supporting ecosystem service. The Bull Run watershed on the Mt. Hood National Forest exemplifies the importance of forests for clean water—it provides fresh water for over 1 million people in the Portland metropolitan area.
Climate change is making it harder for forests to keep water clean and affecting how much water reaches communities. Changes in rainfall, including more heavy rainfall events, can cause water to quickly run off the surface instead of soaking into the ground. This runoff bypasses the forest’s natural filtration system. Intense rainfall can overwhelm the ability of tree roots and canopies to slow water flow and prevent erosion. In some instances, this may lead to flooding, road washouts, and culvert failures. More frequent and extreme disturbance events, such as wildfire, may also increase erosion and the amount of sediment that enters waterways. Warmer temperatures and less snowpack may result in lower summer stream flows. Warmer stream temperatures could leave some communities without a fresh water supply earlier in the summer season.
Pollination
A blanket of lupine under ponderosa pine on the Metolius Preserve in central Oregon. Pollinators, such as the fuzzy-horned bumblebee shown here, collect pollen and transfer it to other plants, fertilizing them so that they later yield fruit or seeds.
Pollinators are vital to Northwest forest ecosystems. By carrying pollen, birds and insects help plants reproduce, which leads to fruit and seed production. Species such as Oregon swallowtails, Rufous hummingbirds, and bumblebees play a role in plant reproduction and support the forest food web. Plants that rely on pollinators feed herbivores, such as elk and deer, which then become food for predators, such as black bears and cougars. Pollinators also help keep wildflower populations healthy. Wildflowers attract nature lovers and provide important habitats for small mammals and birds.
Climate change poses a risk to pollinators. Seasonal shifts in temperature act as cues to let pollinators know when it is time to emerge, lay eggs, and begin pollination. Warmer temperatures can make plants bloom earlier. In the Northwest, some plants now bloom 8 days earlier than they did in the 1950s. This may result in a mismatch between pollinator activity and the emergence of flowering plants; pollinators might not be active when plants start blooming. They could also emerge too early, before flowers open, leaving them without a dependable food source. Drought can cause plants to produce less nectar to conserve energy, reducing the amount of food available to pollinators. These changes could harm some pollinator populations. This would reduce pollination, seed growth, and fruit production, weakening the health of forest ecosystems.
Carbon Cycling
Northwest forests are highly productive, meaning they take in carbon dioxide from the atmosphere and use it to quickly build plant biomass. Forests provide a supporting ecosystem service by cycling carbon, an element that is needed for plants and trees to grow. Forests help regulate carbon by storing it in trees and soil for a long time. This lowers the amount of carbon dioxide in the air, which helps control surface temperatures.
Coastal forests in Oregon, Washington, and Southeast Alaska hold some of the largest aboveground carbon stocks in the United States. This is because of the wet climate, long growing seasons, and the presence of large, mature trees that store carbon for hundreds of years. In drier parts of the Northwest, forests store less carbon overall. More of their carbon is stored underground because dry conditions slow tree growth, and dead plant material on the forest floor breaks down and adds carbon to the soil.
Climate change affects the conditions that increase the intensity of wildfires, which reduce the amount of carbon that forests can store. Warmer temperatures dry out plants, making them burn more easily, which releases carbon. If intense fires occur more often, some forests may turn into shrublands or grasslands, which store less carbon. Longer growing seasons and changing fire patterns also affect how much carbon forests can store in the future.
Cultural and Community Connections
Forests in the Northwest are deeply connected to cultural heritage. They provide both cultural and practical resources for traditional activities. Indigenous communities have long used forests as harvesting grounds. They gather wood, grasses, and bark, and first foods, such as huckleberries and thimbleberries. For example, members of the Quinault Indian Nation collect wood from western redcedar and Douglas-fir for building canoes, carvings, and other traditional crafts.
Forests also inspire art and stories and help people feel connected to the land. Spending time in forests can improve mental and physical health. Visiting with others can build strong community ties, teach survival skills, and help people pass down traditions. Forests offer a space for people from many backgrounds to make memories and honor cultural practices.
As climate change affects forests, it also puts cultural services at risk. Warmer temperatures and longer droughts are stressing important tree species, such as western redcedar. This tree is central to many Indigenous cultures in the Northwest and is used for building, food, and ceremonies. Western redcedar dieback is not fully linked to climate change, but related changes still put this important tree at risk. Huckleberries, another key cultural plant, are also affected. Hotter seasons and more extreme fires are changing the places where huckleberries can grow. In Alaska, caribou are important to many Indigenous communities for food, clothing, and shelter. Warmer winters and earlier fire seasons can reduce their food, forcing them to change migration paths.
Recreation
Snowshoeing towards the summit of Maiden Peak on the Willamette National Forest in Oregon. As snowpack declines with climate change, snowshoe recreationists may be forced to travel to higher elevations or more remote locations.
Northwest forests draw millions of visitors each year and help people connect with nature. National Forests such as Olympic and Siuslaw offer year-round activities, such as hiking, camping, and scenic drives. Their natural beauty also attracts photographers and artists who want to capture the landscape.
The varied experiences provided by forests in the Northwest also support local economies. Visitors help the local economy by spending money on lodging, tours, and entrance fees. From 2017 to 2021, visitors to Pacific Northwest national forests spent an average of $972 per party per trip. Those visiting Alaska’s national forests spent an average of $1,014 per party in 2018.
Climate change is changing how people experience recreation in Northwest forests. Warmer temperatures and more wildfires affect when and how people can safely visit these areas. Wildfires and heavy smoke can lead to trail closures and restrictions on camping, hiking, and other forest activities. Milder winters are shortening the winter recreation season. The optimal snow conditions needed for skiing and snowboarding may occur less frequently or later than usual. Restrictions on when people can use forests may also reduce eco-tourism. Shorter recreation seasons and more closures may lead to fewer visitors and economic losses. In addition, climate change is altering how and when people engage in activities like hunting and fishing. Warmer stream temperatures can harm fish, such as salmon, by disrupting spawning and increasing stress. Warmer winters, longer droughts, and wildfires can shift animal migration, which can change hunting seasons. Rising temperatures and changing weather will continue to affect outdoor activities.
Timber Products
Forests in the Northwest produce a large volume of timber, which supports local economies. Oregon leads the nation in softwood lumber production, and Washington ranks second with its forest industry generating $6 billion in wages each year. Idaho’s forest industry provides roughly 16,000 jobs, and Alaska’s forest industry supports over one thousand jobs.
State | Board feet harvested per year | Jobs |
Alaska (2019) | 178.7 million | 1,100 |
Idaho (2021) | 1 billion | 16,000 |
Oregon (2018) | 3.8 billion | 46,000 |
Washington (2020) | 2 billion | 46,000 |
Northwest forests drive economic growth and play a critical role in mitigating climate change. Trees take up carbon dioxide from the atmosphere and store carbon throughout their lifetime. Lumber and other wood products continue to store carbon throughout their lifespan. When used in buildings or furniture, wood can store carbon for decades or more, keeping it out of the air. This helps balance carbon between land and the atmosphere.
Climate change is already affecting the timber industry in the Northwest. In southwest Oregon, Douglas-fir, the state’s most valuable tree species, is becoming less productive from a combination of factors, including drought and flatheaded fir borer outbreaks. More severe wildfires are also reshaping forest structure and composition. Severe fires and drought can slow tree regrowth. This may reduce future timber supply and make long-term planning harder for the timber industry.
Freres Engineered Wood in Santiam Canyon, Oregon, produces engineered wooden panels and beams that are used in place of steel and concrete for large buildings. The carbon that trees stored during their lifespan remains locked away in wood even after being harvested. Manufacturing harvested wood products like timber for construction uses 90 percent fewer fossil fuels compared to steel and concrete.
Nontimber Forest Products
Huckleberries in the Gifford Pinchot National Forest of southwest Washington
Northwest forests provide a wealth of economically significant nontimber forest products such as edible mushrooms, including Oregon truffles, berries, floral greens, and medicinal plants. Huckleberries are important to many communities, and wild mushrooms, such as morels and chanterelles are popular for both personal and commercial use. Demand for nontimber forest products continues to grow, driven by local and global export markets.
Climate change is altering the availability and productivity of nontimber forest products. Rising temperatures, shifting precipitation patterns, and more frequent extreme weather events may harm Northwest forests and their resources. Huckleberries, for example, need certain climate and soil conditions. As these change, yields may drop or shift to new areas. This puts important nontimber forest products at risk across the region.
Resources for Adaptive Management
Land managers can integrate climate change adaptation into management and consider ecosystem services to help enhance forest health and resilience. This approach can also ensure that forests continue to provide critical benefits in the future.
Warming temperatures, changing precipitation patterns, and growing demand for resources will keep challenging forest management. Climate change adaptation actions and management practices aimed at enhancing forest health and improving forest resilience to insects, wildfire, and drought can help ensure that forests continue to provide valuable ecosystem services. Specific practices will depend on forest type and ownership but may include those highlighted in the following resources:
Healthy forests in Oregon, Washington, Idaho, and Alaska are closely tied to healthy communities. New examples of adaptation illustrate how land managers and forest owners are adjusting forest management so that forests can continue providing ecosystem services under climate change.
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