Environment Planet Earth Get to Know North America's Temperate Rainforests The Pacific Northwest is home to the only temperate rainforest on the continent. By Jaymi Heimbuch Jaymi Heimbuch Twitter Writer California Polytechnic State University, San Luis Obispo Jaymi Heimbuch is a writer and photographer specializing in wildlife conservation, technology, and food. She is the author of "The Ethiopian Wolf: Hope at the Edge of Extinction." Learn about our editorial process Updated March 2, 2022 Share Twitter Pinterest Email Treehugger / Julie Bang Environment Weather Outdoors Conservation In This Article Expand Redwoods Predators Roosevelt Elk Salmon Birds of Prey Understory Epiphytes Tongass National Forest When we hear the word "rainforest", most of us immediately think of the hot tropical jungles running along the equator like a green belt. However, a rainforest is simply a forest that receives a lot of rainfall, and there are areas of the world with somewhat less tropical temperatures that are also home to rainforests. Only seven temperate rainforest ecosystems exist around the world, and North America is home to one of them. The Pacific Northwest temperate rainforests, which range from northern California to British Colombia, exist in what is the world's largest temperate rainforest ecoregion. It receives more than 55 inches of rain annually. It's worth noting that definitions of the Pacific Northwest vary, from the simplest—California, Oregon, Washington state, and the Canadian province of British Columbia—to broader definitions that include southeast Alaska and parts of Wyoming and Montana in addition to the core states. Home to a rich diversity of species, many of which are found nowhere else in the world, this temperate rainforest is an incredible place to explore. And with one of the highest levels of biomass of any place on Earth, you are certain to come across something beautiful on every step of your journey across the forest floor. Coastal redwoods are a special part of temperate rain forests in the Pacific Northwest. (Photo: Peerasith Patrick Triratpadoongphol/Shutterstock) Redwoods Giants live in the temperate rainforests of the Pacific Northwest. While Sasquatch is a myth (or is it?), the true unbelievable giants are the coastal redwoods. The unique species found in Northern California are some of the most massive, tallest and oldest trees on the planet. They rely on the moist air to take in enough water to sustain their enormous stature, and are dependent upon coastal fog for survival. Redwood trees are an ecosystem in and of themselves, with boughs hosting species of animals that never touch the ground. Redwoods are found along the Pacific Coast from the central coast of California to the southern border of Oregon. Top-level carnivores — as this mountain lion cub will become — are a critical part of temperate rain forest ecosystems. (Photo: iva/Shutterstock) Predators Large predators are at home in the temperate rainforests of North America, from wolves to bears to mountain lions. This mountain lion cub will one day grow to be upward of 6 feet long and weigh somewhere between 85 and 180 pounds. Mountain lions—also known as cougars and pumas, depending on the location—play a critical role in maintaining deer populations, which in turn maintain the health of the forest understory. Predators are as important to the perpetuation of North America's temperate rainforests as the rain itself. Temperate rainforests are also home to bobcats, lynx, coyotes, and many more important predators. Roosevelt elk are the largest species of elk, and are considered the 'gardeners' of the forest. (Photo: Steve Bower/Shutterstock) Roosevelt Elk The temperate rainforest of the Pacific Northwest is also home to the largest subspecies of elk on the continent: Roosevelt elk. Named for President Theodore Roosevelt, the subspecies also goes by the name Olympic elk in part because Olympic National Park in Washington state is home to the largest herd left in the wild. The Hoh Rainforest is an excellent place to spot these huge ungulates as they browse on ferns and lichens. "Elk play an important part in life cycle of the forest by clearing understory vegetation, which makes way for other plant and animal species," notes Oregon Wild. "Currently habitat loss and fragmentation due to logging and road construction threaten these unique elk." In the Pacific northwest, spawning salmon play a significant role in fertilizing the temperate rainforest understory. (Photo: Maksimilian/Shutterstock) Salmon While we think of temperate rainforests as part of the land, animals arriving from the wide open ocean play a surprisingly important role in the rainforests' overall health—specifically, salmon. As salmon swim upstream during spawning season, wolves and bears catch them and carry them into the forest to dine. The scraps become food for other smaller creatures, and end up fertilizing the soil for plants as they decompose. Photographer Amy Gulick created a book called "Salmon In The Trees," which explores the connection between fish returning to spawn and how they feed the flora and fauna miles inland. Owls add to the intrigue of moss- and lichen-covered conifer trees. (Photo: Jan Zoetekouw/Shutterstock) Birds of Prey Raptors also play a role in the rain forests of the Pacific Northwest. Bald eagles are perhaps the most famous and gregarious, but tucked away in the branches of the trees are spotted owls and barred owls, Northern saw-whet owls and Northern goshawks, osprey and kestrels. As raptors eek out a living in the forests, they sometimes clash with one another. The decline of spotted owls due to logging in old-growth forests in the Pacific Northwest lead to a heated controversy between conservationists and the timber industry. Eventually, the species gained protections, but today they face the competition of barred owls, a larger and more aggressive species that drives them from their remaining habitat. How we go about preserving the species is as problematic as ever before. Smithsonian writes: "As climate chaos disrupts migration patterns, wind, weather, vegetation and river flows, unexpected conflicts will arise between species, confounding efforts to halt or slow extinctions. If the spotted owl is any guide, such conflicts could come on quickly, upend the way we save rare plants and animals, and create pressure to act before the science is clear. For spotted owls 'we kind of put the blinders on and tried to only manage habitat, hoping things wouldn't get worse,' [Eric] Forsman said. 'But over time the barred owl's influence became impossible to ignore.'" The understory of temperate rain forests hold a significant amount of biomass. (Photo: Timothy Epp/Shutterstock) Understory The understory and forest floor is where much of the biodiversity is found in temperate rainforests here. (They're differentiated from the canopy, which is the top layer.) Aside from the tall conifers, there are smaller trees that thrive in shade like maple and dogwood, as well as shade-loving shrubs like Pacific rhododendron, blackberries, and salmonberries. It's here that you can experience lush ferns like Oregon oxalis, sword fern and lady fern. Mosses cover fallen logs, helping to retain moisture, and mushrooms sprout up from the fungus spiderwebbed under the soil and in decaying plant life. Cool temperatures mean that material breaks down more slowly than in tropical rainforests, but the soil is rich and nutrient-filled from the ongoing decomposition. Mosses and lichens are some of the epiphytes living in the trees of temperate rain forests. (Photo: Jaymi Heimbuch) Epiphytes Along with the flora that takes root in the soil is flora that uses no roots at all. Thanks to the mild temperatures and abundance of moisture, epiphytes grow well in the temperate rainforest. These are the mosses, lichens, ferns, and other plants that grow on other plants, such as across the boughs of trees. According to Oregon State, "Epiphytes are a major component of the diversity in forests of the Pacific Northwest. The number of species of epiphytic bryophytes and macrolichens is typically 40-75 species in a 1-acre plot. This often exceeds the number of flowering plant species in the same forest." Some species found in this region range from the tiny false pixie cup lichen to the lung-wort, which looks a bit like a small cabbage-leaf, and from licorice fern to the feathery veils of cat-tail moss. Explore the Wide and Wonderful World of Epiphytes A view of Tongass National Forest in Alaska. (Photo: dshumny/Shutterstock) Tongass National Forest According to the World Wildlife Fund, "More than a quarter of the world's coastal temperate rain forests occur in the North Pacific coastal forests ecoregion of southeast Alaska." The Tongass National Forest is a large swath of temperate rainforest located in southeast Alaska. It's the largest national forest in the United States—and the largest remaining temperate rainforest in the world. It's here that you can find some of the last old growth temperate rainforest on the continent. If you like walking through fairytale-like forests, rich with ferns and moss-covered conifers, quiet but for the sound of bird calls or rushing streams, then this unique ecosystem of the Pacific Northwest is something you must visit.