Redwood trees do grow in Washington State, but are not native to the region. They exist there due to human planting. While some specimens thrive, they do not form the extensive natural ecosystems seen in their native ranges.
Understanding Redwood Species and Their Natural Homes
Two primary species are commonly referred to as “redwoods”: the Coast Redwood (Sequoia sempervirens) and the Giant Sequoia (Sequoiadendron giganteum). Coast Redwoods are the tallest living trees, frequently reaching over 350 feet in height. Their natural range is a narrow strip along the Pacific Coast, extending from central California into a small portion of southern Oregon, typically no more than 50 miles inland.
Giant Sequoias, while not as tall, are the most massive individual trees on Earth, with average heights between 164 and 279 feet and large trunk diameters. These trees are naturally found in scattered groves on the western slopes of California’s Sierra Nevada mountains. They thrive at higher elevations, generally between 4,600 and 7,050 feet.
Redwood Presence in Washington State
Any redwoods observed in Washington were introduced by people, often planted as ornamental trees in various settings. These are primarily individual planted specimens rather than naturally occurring forests. These planted redwoods can be found in numerous locations across the state, particularly in western Washington where the climate is milder.
Publicly accessible examples include:
Washington State Capitol Campus in Olympia
Port Angeles City Pier Park
University of Washington Campus in Seattle
Tacoma’s Point Defiance Park and Jefferson Park
Locations in North Bend, Auburn, Issaquah, Elbe, and SeaTac
While these trees can grow quite large, they are generally younger and smaller than their ancient counterparts in California. Washington does not host the sprawling, dense redwood groves characteristic of their native habitat.
Environmental Factors for Redwood Survival
Coast Redwoods require specific environmental conditions for optimal growth, including high humidity, consistent rainfall, and mild temperatures, ideally between 45 and 70 degrees Fahrenheit. Summer fog is particularly important for these trees, providing needed moisture during dry periods by allowing them to absorb water directly through their leaves. They also prefer deep, well-drained soils that are acidic to neutral, with a pH between 5.5 and 7.0.
Giant Sequoias also have distinct needs, thriving in a humid climate characterized by dry summers and snowy winters. They can tolerate a wider temperature range, from -12 to 104 degrees Fahrenheit, but are typically found in areas with January minimums between 21 and 34 degrees Fahrenheit and July maximums between 75 and 84 degrees Fahrenheit. These trees require ample water, often sourced from snowpack, and grow best in deep, well-drained sandy loams with a pH ranging from 5.5 to 7.5.
Washington’s climate, while wet, generally features colder winters and lacks the consistent summer fog belts that Coast Redwoods rely on for moisture. These climatic and soil differences, compared to the redwoods’ native ranges, limit their natural growth and reproduction from seed in Washington. Although planted redwoods can survive, the conditions are not conducive to the formation of self-sustaining natural forests.