Western redcedar

Western redcedar
Name	Western redcedar
Genus	Thuja
Species	plicata
Family	Cupressaceae
Common names	Pacific redcedar, giant cedar
Authority	Donn ex D.Don

Western redcedar is a long-lived conifer of the Pacific Northwest renowned for its durable, decay-resistant timber and central role in Indigenous cultures across the North American coast. It attains large sizes in moist coastal forests, shapes forest structure and biodiversity, and features heavily in traditional art, architecture, and economy. The species is a focal point for conservation, forestry, and cultural heritage debates involving governments, tribes, environmental organizations, and industry.

Description

The tree develops a conical to buttressed bole with fibrous, stringy bark and aromatic, scale-like foliage; mature crowns may resemble those of other large conifers such as Coast Douglas-fir and Western hemlock. Height commonly exceeds 40–70 m in old-growth stands similar to trees found in Olympic National Park, Gwaii Haanas National Park Reserve, Pacific Rim National Park Reserve, and Mount Rainier National Park. Needles are arranged in flattened sprays comparable to those of Eastern redcedar and cones are small and winged, like cones of members of Cupressaceae such as Lawson cypress. Wood is light and straight-grained, properties prized by builders and craftspersons working in places such as Vancouver, Seattle, Portland, Oregon, Kodiak Island, and Prince Rupert.

Taxonomy and Nomenclature

Thuja plicata belongs to the genus Thuja within the family Cupressaceae, a group that also includes genera such as Chamaecyparis, Cupressus, and Juniperus. The specific epithet plicata was applied by botanists in the tradition of David Don and follows botanical treatments in works by scholars associated with institutions like the Royal Botanic Gardens, Kew, the Smithsonian Institution, and the Royal Society. Common names reflect colonial and Indigenous usages documented in ethnobotanical surveys conducted by researchers at universities such as the University of British Columbia, University of Washington, and the University of Alaska Fairbanks. Taxonomic debates have referenced historical collections housed in herbaria such as those at the Field Museum, Royal Botanic Garden Edinburgh, and the New York Botanical Garden.

Distribution and Habitat

The species' natural range spans coastal and foothill zones from northern California through Oregon, Washington (state), and British Columbia to southeast Alaska, including islands of the Alexander Archipelago and the Queen Charlotte Islands (Haida Gwaii). It occupies low-elevation wet sites—floodplains, swamp margins, and maritime forests—often co-occurring with Sitka spruce, Red alder, Bigleaf maple, Pacific silver fir, and Western redcedar-associate communities protected within landscapes managed by agencies such as the U.S. Forest Service, Parks Canada, and state/provincial forestry departments. Habitats include old-growth stands in federally designated areas like Tongass National Forest, Mount Baker–Snoqualmie National Forest, and conservation lands held by organizations such as The Nature Conservancy and Indigenous nations like the Haida Nation and Tlingit communities.

Ecology and Life History

Western redcedar exhibits shade tolerance and longevity, with individuals living for centuries and sometimes millennia in refugia similar to ancient trees recognized by programs at the U.S. National Park Service and provincial heritage registries. Reproduction is by small wind-dispersed seeds, and regeneration dynamics interact with disturbance regimes including floods, windthrow, and fire studied by ecologists at institutions such as Oregon State University, University of Victoria, and University of British Columbia. It hosts a range of epiphytes and fungi—mycorrhizal partners and wood-decay fungi monitored by research groups at the Canadian Forest Service and the Pacific Northwest Research Station—and supports wildlife including cavity-nesting birds documented by the Audubon Society, mammals noted by the World Wildlife Fund, and invertebrate communities cataloged by natural history museums like the Royal BC Museum.

Human Uses and Cultural Significance

The species is central to the material cultures of Indigenous peoples such as the Haida, Tsimshian, Kwakwaka'wakw, Nuu-chah-nulth, Coast Salish, and Tlingit, who used its planks for cedar canoes, longhouses, totem poles, and clothing, practices described in ethnographies by scholars associated with museums including the British Museum, the Canadian Museum of History, and the Smithsonian National Museum of the American Indian. European colonists and commercial forestry enterprises in cities like Vancouver and Seattle exploited the wood for shingles, siding, and utility poles, influencing economic histories recorded by the Hudson's Bay Company archives and regional timber companies such as Weyerhaeuser and Interfor. The tree also has ceremonial roles recognized by tribal governments and cultural centers like the Bill Reid Gallery, Museum of Vancouver, and festivals supported by cultural agencies including Canada Council for the Arts and the National Endowment for the Arts.

Conservation and Threats

Conservation status assessments by bodies including the IUCN, regional ministries of forests, and federal agencies consider threats from logging, land conversion, and climate-driven changes in precipitation and pathogen dynamics studied by researchers at Environment and Climate Change Canada, NASA, and the US Geological Survey. Recent concerns include increased drought stress, bark beetle outbreaks similar to those impacting Ponderosa pine and Lodgepole pine, and novel pathogens monitored by the Canadian Food Inspection Agency and the USDA Forest Service. Protection efforts involve collaborations among Indigenous governments, conservation NGOs such as Sierra Club, municipal authorities in places like Vancouver Island, and international frameworks addressing old-growth preservation in the wake of campaigns by groups including Greenpeace and the David Suzuki Foundation. Sustainable forestry certification schemes like those of the Forest Stewardship Council and research into assisted migration conducted by botanical gardens including the University of British Columbia Botanical Garden and the Arnold Arboretum form parts of adaptive management responses.

Category:Thuja Category:Trees of North America