Western red cedar (Thuja plicata)

The Western red cedar (Thuja plicata) is a fast-growing evergreen tree native to the Pacific Northwest of the United States and Canada. It is also known by a variety of other names, including the Western red cedar, giant red cedar, giant red cedar, Western arborvitae, shinglewood, or canoe cedar. It has been an integral part of the cultures of many Native American tribes of the Pacific Northwest. The wood of the Western red cedar has great economic value in the twenty-first century, and it is harvested for many industrial purposes. It is primarily used in roofing due to its light weight and attractive coloring, while its fragrant leaf oil is used in the production of soaps and deodorants. The leaves of this tree are eaten by many species of deer throughout the year, making it a key species of the region's ecosystem.

At maturity, the Western red cedar generally reaches heights of up to 70 feet (21 meters) and widths of 25 feet (7.5 meters) in diameter, although they can grow much bigger. The largest surviving example of this tree is the Cheewhat Lake Cedar found on Vancouver Island in British Columbia. This specimen has a total volume of 15,856 cubic feet (449 cubic meters) and a height of 182 feet (55.5 meters). One centuries-old tree from Vancouver Island that was felled in the twentieth century was 233 feet (71 meters) in height, which is likely an extraordinary example of the potential height that a Western red cedar may reach when left undisturbed in ideal conditions.

Background

The Western red cedar is part of the Thuja family of coniferous trees. Coniferous trees are almost exclusively evergreen trees, meaning that they do not shed their leaves on a seasonal basis like deciduous trees. The Thuja genus of trees consists of five species, three of which are found in Asia, while two are located in North America. In addition to the Western red cedar, Thuja occidentalis—the northern white cedar—is found in large numbers across the northern United States and Canada.

The trees of the Thuja genus are part of the broader taxonomic family of trees known as the Cupressaceae, which includes all species of cypresses. The Western red cedar is among the largest species of cypress trees in the world. However, other genera of the Cupressaceae family include the coastal redwoods and the giant sequoias of California—which are the tallest and largest species of trees in the world, respectively. Members of the Cupressaceae family have spiral leaves and orange to brown bark. Despite being deciduous, old leaves are shed after two to ten years in small sprays rather than as individual leaves. Thuja trees have diamond-shaped needles and produce both male and female cones on a single plant.

The species of Thuja are sometimes known as arborvitae (meaning tree of life), and several species—including T. plicata—are cultivated for ornamental purposes. They are attractive and fragrant evergreens, often used as hedges and windscreens. T. plicata is less hardy than some other Thuja species, but it is disease- and pest-resistant, which makes it a valuable ornamental plant, particularly in locations with similar climate conditions to its native habitat. Several distinct cultivars bred to display different leaf colors and heights have been developed. T. occidentalis trees are more commonly used in the ornamental market due to their greater durability.

The Western red cedar grows in cool, moist habitats ranging from sea level to elevations of up to 1500 feet (2300 meters). As they have developed the ability to grow easily in the shade of other trees, they are generally found in mixed forests instead of natural stands of pure cedar forests. In their native range, they are adaptive and hardy and can be found in swamps, ravines, poorly drained soils, and rocky slopes.

Physically, they are sometimes described as resembling cathedrals because they naturally develop into a pyramidal shape. The needles grow in a fan shape in a glossy green color. The small seed cones are small and oval-shaped with eight to fourteen seeds per cone. The bark is reddish-brown and flaky, with pieces growing in flat, uneven ridges over one another. Older trees often have dead tops, with many new leaders growing around the old, barren portions. Trees grow rapidly but mature slowly, with cone production only starting when a tree reaches ten to twenty years of age.

Overview

The Western red cedar was a particularly important tree to such coastal Native American tribes as the Quinault, Chehalis, Cowlitz, and Makah. Its range marked the edge of the cultural boundary of this family of tribes. They held the red cedar tree in such high esteem that they were reluctant to cut down living trees. Instead, they used fallen logs and branches or cut planks from living trees in such a way that allowed them to recover. They used these trees for a variety of purposes, including for the construction of homes and canoes. In addition, female tribe members used the bark to make such clothing items as skirts, capes, and dresses. The lining of bark was used to create slow burn matches, mats, and padding for baby cradles, while ropes, baskets, and plates were built from stray branches, roots, and tree limbs.

The Western red cedar also had medical and mythological value to native tribes. According to one legend, people seeking to find strength in their own lives could lean against the red cedar tree and borrow from its inherent power. Tribes also derived a variety of medicinal uses from parts of the cedar. The bark was used in traditional medicine practices to help bring about menstruation or to ease kidney trouble. The red cedar was further used to heal sores, to break a fever, or in medicines used to treat such conditions as toothaches and coughs. However, perhaps the most iconic use of red cedar wood by Native Americans was for the creation of totem poles, as the wood of T. plicata is naturally rot-resistant.

After the arrival of European colonists to the Pacific Northwest, the tree became one of the centerpieces of a burgeoning timber industry. Because it is colorful, fragrant, and lightweight, it remains a popular wood in home construction, particularly for use as wood shingles. It may be used in the manufacturing of fence posts, utility posts, wooden containers, boats, and paper pulp. The leaf oil, from which the tree's distinctive fragrance originates, is used to scent soaps, insecticides, medicines, and perfumes. Doctors and bioresearchers have discovered that T. plicata may also have a variety of medicinal applications.

Bibliography

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