Thuja plicata

Last updated

Thuja plicata
Thuja plicata Vancouver.jpg
An old tree in Vancouver
Scientific classification Red Pencil Icon.png
Kingdom: Plantae
Clade: Tracheophytes
(unranked): Gymnosperms
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Cupressaceae
Genus: Thuja
Species:
T. plicata
Binomial name
Thuja plicata
Donn ex D.Don
Thuja plicata range.png
Range of T. plicata in the Pacific Northwest

Thuja plicata is an evergreen coniferous tree in the cypress family Cupressaceae, native to western North America. Its common name is western redcedar [2] (western red cedar in the UK), [3] and it is also called Pacific redcedar, giant arborvitae, western arborvitae, just cedar, giant cedar, or shinglewood. [4] It is not a true cedar of the genus Cedrus .

Contents

Description

Thuja plicata is a large to very large tree, ranging up to 45 to 70 metres (150 to 230 ft) tall and 2.4 to 7 m (8 to 23 ft) in trunk diameter. [5] [6] [7] Trees growing in the open may have a crown that reaches the ground, whereas trees densely spaced together will exhibit a crown only at the top, where light can reach the leaves. [8] The trunk swells at the base and has shallow roots. [5] The bark is thin, gray-brown and fissured into vertical bands. [5] As the tree ages, the top is damaged by wind and replaced by inferior branches. [5] The species is long-lived; some trees can live well over a thousand years, with the oldest verified aged 1,460. [6] [7]

The foliage forms flat sprays with scale-like leaves in opposite pairs, with successive pairs at 90 degrees to each other. The foliage sprays are green above and green marked with whitish stomatal bands below; they are strongly aromatic, with a scent reminiscent of pineapple when crushed. The individual leaves are 1 to 4 millimetres (132 to 532 in) long and 1 to 2 mm (132 to 332 in) broad on most foliage sprays, but up to 12 mm (12 in) long on strong-growing lead shoots. [6] [7] The foliage of individual branchlets turns orange-brown before falling off in autumn. [5]

The cones are slender, 10 to 18 mm (38 to 1116 in) long, and 4 to 5 mm (532 to 316 in) broad, with 8 to 12 (rarely 14) thin, overlapping scales. They are green to yellow-green, ripening brown in fall about six months after pollination, and open at maturity to shed the seeds. The seeds are 4 to 5 mm (532 to 316 in) long and 1 mm (132 in) broad, with a narrow papery wing down each side. The pollen cones are 3 to 4 mm (18 to 532 in) long, red or purple at first, and shed yellow pollen in spring. [6] [7]

Chemistry

The heartwood of western redcedar contains different chemical substances, such as plicatic acid, thujaplicatin methyl ether, hinokitiol and other thujaplicins, β-thujaplicinol, thujic acid, methyl thujate, 1,4-cineole and γ-eudesmol. [9] Plicatic acid is believed to be the main irritant and contact allergen responsible for provoking allergic reactions and asthma exaggeration and leading to occupational asthma in woodworkers that are exposed to western redcedar wood dust. [10] Thujaplicins serve as natural fungicides, [11] [12] and thereby prevent the wood from rotting. This effect lasts around a century even after the tree is felled. However, thujaplicins are only found in older trees. Saplings do not produce the chemical, causing them to often develop rot at an early stage, causing some trees to grow with a somewhat hollow trunk, as the tree moves to heal itself as it grows. [13] Due to their fungicidal and anti-browning properties, thujaplicins are used in agriculture for fungal diseases and to prevent post-harvest decay. [14] [15] Thujaplicins, as other tropolones, are potent chelating agents and bind divalent metal ions. [16] Basic and animal studies have shown that thujaplicins may have other biological properties, including antibacterial, antiviral and antioxidant activities, [17] however reliable evidence on their effectiveness is still lacking.

Taxonomy and name

Thuja plicata is one of two Thuja species native to North America, the other being Thuja occidentalis . The species name plicata derives from the Latin word plicāre and means 'folded in plaits' or 'braided,' a reference to the pattern of its small leaves. [8]

Most authorities, both in Canada [18] [19] and the United States [20] [2] [21] [22] transliterate the English name in two words as 'western redcedar', or occasionally hyphenated as 'western red-cedar', [7] to indicate that it is not a true cedar ( Cedrus ), but it also appears as 'western red cedar' in some popular works. In the American horticultural trade, it is also known as the giant arborvitae, by comparison with arborvitae for its close relative Thuja occidentalis. Other names include giant redcedar, Pacific redcedar, shinglewood, British Columbia cedar (being the province's official tree), [5] canoe cedar, and red cedar. [6] [13] Arborvitae comes from the Latin for 'tree of life'; coincidentally, Native Americans of the West Coast also address the species as "long life maker". [13]

One endonymous name for the tree is the Halkomelem word xepá:y, [23] from the roots xíp, meaning 'scratch' or 'line', and á:y, 'bark'; [24] the former root may be in reference to both the lined or "folded/braided" appearance of the bark and the tree's ubiquity in carving and other forms of woodwork.

Distribution and habitat

Thuja plicata is among the most widespread trees in the Pacific Northwest. It is associated with Douglas-fir and western hemlock in most places where it grows. It is found in moist areas, where precipitation exceeds 75 centimetres (30 in) annually, west of the Cascade Range crest  from central South East Alaska (near the village of Kake) to northern California (growing closer to the coast at the north and south extremes) and inland from central-southeast British Columbia through the Idaho Panhandle. [5] It is usually found from sea level to elevations of 1,100 m (3,600 ft), [5] but grows at altitudes of up to 2,290 m (7,510 ft) at Crater Lake in Oregon [20] and 1,500 m (4,900 ft) in Idaho. [5] In addition to growing in lush forests and mountainsides, western redcedar is also a riparian tree, growing in many forested swamps and streambanks in its range. [25] The tree is shade tolerant and able to reproduce under dense shade. [26]

It has been introduced to other temperate zones, including further north in Alaska, western Europe, Australia (at least as far north as Sydney), New Zealand, [27] [28] the eastern United States (at least as far north as Central New York),[ citation needed ] and higher elevations of Hawaii. [29]

The species is naturalized in Britain. [30]

Ecology

Use by wildlife

Western redcedar foliage, especially that of saplings, is an important food source year-round for browsing ungulates such as Roosevelt elk and black-tailed deer, especially during the winter months when little else is available. [31] The seeds are eaten by birds and rodents.

Western redcedar provides cover for bears, raccoons, skunks, and other animals which nest inside trunk cavities. It is used as a nest tree by cavity-nesting bird species such as yellow-bellied sapsuckers, hairy woodpeckers, tree swallows, chestnut-backed chickadees, and Vaux's swifts. [31]

Thuja plicata is a host to several destructive insect species such as the western cedar borer, cedar bark beetle, gall midge, and conifer seedling weevils. [32] [31]

Forest succession

Western redcedar appears in all stages of forest succession, but as it is one of the most shade-tolerant species in the Rocky Mountains and Pacific Northwest it is considered to be a climax species along with western hemlock. [31] It will readily establish and grow in the shade of other, less shade-tolerant species such as red alder, black cottonwood, or Douglas-fir, and prevent seedlings of those species from establishing themselves in its shade. However, western hemlock and Pacific silver fir are more tolerant of shade. [5] Western redcedar can also reproduce vegetatively via layering. [5]

Fire ecology

It is considered to have low to moderate fire resistance, as its thin bark, shallow roots, low dense branching habit and flammable foliage confer little protection. Smaller trees are commonly killed by fire, but larger specimens often survive due to their size if they are not completely girdled. The intervals between fires within western redcedar stands tend to be very long, from 50 up to 350 years or more. [31]

Pathology

Western redcedar shows susceptibility of varying degrees to the following soil pathogens: Armillaria ostoyae, Fomitopsis pinicola, Heterobasidion annosum, Phaeolus schweinitzii, Phellinus weirii, Rhizinia undulata, and Postia sericeomollis. [33]

While western redcedar is a host to P. weirii, the fungus which causes the disease laminated root rot, redcedar is rated as resistant while other conifers are rated as highly susceptible or susceptible. [34] Instead of laminated root rot, P. weirii in western redcedar expresses as a butt rot that can extend 2–3 m up the boles of living trees with the most extreme cases reaching 10 m. While the heart rot caused by the redcedar form of P. weirii does not kill the tree outright, it does severely weaken the lower portion of the bole which makes the tree highly susceptible to stem breakage.

P. sericeomollis is responsible for brown cubical butt and pocket rot of cedar. It is the second-most common cause of decay in western redcedar following P. weirii. Rather than forming a single column of decay in the heartwood, though, P. sericeomollis tends to cause rings or pockets of decay in the lower bole. [35]

In addition to P. weirii, western redcedar is also less susceptible to H. annosum and A. ostoyae than other conifer species. [36] Studies have found that western redcedar produces a phytochemical called thujaplicin which has been credited with granting the species its natural resistance to fungal attacks. [12] Because of these natural defenses, it has been suggested that western redcedar may serve as a suitable alternative to other conifers when regenerating a site affected by these pathogens. [37]

Cultivation

Like its relative Thuja occidentalis and many other conifer species, Thuja plicata is grown as an ornamental tree, and for screens and hedges, throughout the world in gardens and parks. A wide variety of forms, sizes, and colours is available. [38]

Cultivars

The following cultivars have gained the Royal Horticultural Society's Award of Garden Merit:

Uses

In indigenous societies

Klallam people and canoe, ca. 1914 Klallam people near canoe.jpg
Klallam people and canoe, ca. 1914

Western redcedar has an extensive history of use by Native Americans of coastal Oregon to southeast Alaska. Some northwest coast tribes refer to themselves as "people of the redcedar" because of their extensive dependence on the tree for basic materials. The wood has been used for constructing housing and totem poles, and crafted into many objects, including masks, utensils, boxes, boards, instruments, canoes, vessels, houses, and ceremonial objects. Western redcedar is also associated with a long tradition of curing and cooking fish over the open fire. Roots and bark are used for baskets, bowls, ropes, clothing, blankets, and rings. [44] [45]

A huge number of archaeological finds point to the continuous use of redcedar wood in native societies. Woodworking tools dating between 8,000 and 5,000 years ago, such as carved antlers, were discovered in shell middens at the Glenrose site, near Vancouver, British Columbia. [46] In Yuquot, on the west coast of Vancouver Island, tools dating 4,000 to 3,000 years old have been found. [46] The Musqueam site, also near Vancouver, yielded bark baskets woven in five different styles, along with ropes and ships dated to 3,000 years ago. At Pitt River, adzes and baskets were dated around 2,900 years ago. Wooden artifacts 1000 years old were unearthed on the east coast of Vancouver Island. [47]

Red cedar was used extensively wherever it was found along the northwest coast (British Columbia, Washington state, parts of Alaska). Evidence of this use is found in CMTs (Culturally Modified Trees) that are found throughout the coast. When First Nations people removed the bark from cedars, it left a scar which is considered a CMT. Other types of harvest (for planks, tinder, and other uses) leave different types of evidence of cultural modification.

A legend amongst the Coast Salish peoples describes the origins of the western redcedar. In this legend, there was a generous man who gave the people whatever they needed. When the Great Spirit saw this, he declared that when the generous man died, a great redcedar tree will grow where he is buried, and that the cedar will be useful to all the people, providing its roots for baskets, bark for clothing, and wood for shelter. [46]

Tools

The wood was worked primarily with the adze, which was preferred over all other tools, even ones introduced by Europeans. Alexander Walker, an ensign on the fur trade ship Captain Cook, reported that the indigenous peoples used an elbow adze, which they valued over tools brought by the Europeans, such as the saw or the axe, going so far as to modify traded tools back into an adze. Tools were generally made from stone, bone, obsidian, or a harder wood such as hemlock. A variety of hand mauls, wedges, chisels, and knives are also used.

Excavations done at Ozette, Washington, turned up iron tools nearly 800 years old, far before European contact. When James Cook passed the area, he observed that almost all tools were made of iron. [48] There has been speculation on the origin of these iron tools. Some theories include shipwrecks from East Asia or possible contact with iron-using cultures from Siberia, as hinted in the more advanced woodworking found in northern tribes such as the Tlingit. [48] [49] [50] [51]

Wood

A totem pole outside a six-post house at the University of British Columbia Moa-4.jpg
A totem pole outside a six-post house at the University of British Columbia

Harvesting redcedars required some ceremony and included propitiation of the tree's spirits as well as those of the surrounding trees. In particular, many people specifically requested the tree and its brethren not to fall or drop heavy branches on the harvester, [52] a situation which is mentioned in a number of different stories of people who were not sufficiently careful. Some professional loggers of Native American descent have mentioned that they offer quiet or silent propitiations to trees which they fell, following in this tradition.

Felling of large trees such as redcedar before the introduction of steel tools was a complex and time-consuming art. Typically the bark was removed around the base of the tree above the buttresses. Then some amount of cutting and splitting with stone adzes and mauls would be done, creating a wide triangular cut. The area above and below the cut would be covered with a mixture of wet moss and clay as a firebreak. Then the cut would be packed with tinder and small kindling and slowly burned. The process of cutting and burning would alternate until the tree was mostly penetrated through, and then careful tending of the fire would fell the tree in the best direction for handling. This process could take many days. Constant rotation of workers was involved to keep the fires burning through night and day, often in a remote and forbidding location. [53]

Once the tree was felled, the work had only just begun, as it then had to be stripped and dragged down to shore. If the tree was to become canoes, then it would often be divided into sections and worked into rough canoe shapes before transport. If it were to be used for a totem pole or building materials, it would be towed in the round to the village. [54] Many trees are still felled in this traditional manner for use as totem poles and canoes, particularly by artists who feel that using modern tools is detrimental to the traditional spirit of the art. Non-traditionalists simply buy redcedar logs or lumber at mills or lumber yards, a practice that is commonly followed by most working in smaller sizes such as for masks and staves.

Because felling required such an extraordinary amount of work, if only planks for housing were needed, these would be split from the living tree. The bark was stripped and saved, and two cuts were made at the ends of the planking. Then wedges would be pounded in along the sides and the planks slowly split off the side of the tree. [55] Trees which have been so harvested are still visible in some places in the rainforest, with obvious chunks taken off of their sides. Such trees usually continue to grow perfectly well, since redcedar wood is resistant to decay. Planks are straightened by a variety of methods, including weighing them down with stones, lashing them together with rope, or forcing them between a line of stakes. [56]

Illustration of women pulling bark from a tree, from Indian Legends of Vancouver Island by Alfred Carmichael Thuja plicata bark.png
Illustration of women pulling bark from a tree, from Indian Legends of Vancouver Island by Alfred Carmichael

Redcedar wood is used to make huge monoxyla canoes in which the men went out to high sea to harpoon whales and conduct trade. [57] One of those canoes, a 12-metre (38 ft) craft dug out about a century ago, was bought in 1901 by Captain John Voss, an adventurer. He gave her the name of Tilikum ('Relative' in Chinook jargon), rigged her, and led her in a hectic three-year voyage from British Columbia to London. [58]

Redcedar branches are very flexible and have good tensile strength. They were stripped and used as strong cords for fishing line, nets, [5] rope cores, twine, and other purposes where bark cord was not strong enough or might fray. Both the branches and bark rope have been replaced by modern fiber and nylon cordage among the aboriginal northwest coast peoples, though the bark is still in use for the other purposes mentioned above.

Bark

At the right time of year, the bark is easily removed from live trees in long strips. It is harvested for use in making mats, rope and cordage, basketry, rain hats, clothing, and other soft goods. The harvesting of bark must be done with care, as stripping too much bark will kill the tree. To prevent this, the harvester usually only harvests from trees which have not been stripped before. [59] After harvesting, the tree is not used for bark again, although it may later be felled for wood. Stripping bark is usually started with a series of cuts at the base of the tree above any buttresses, after which the bark is peeled upwards. To remove bark high up, a pair of platforms strung on rope around the tree are used and the harvester climbs by alternating between them for support. Since redcedars lose their lower branches as all tall trees do in the rainforest, the harvester may climb 10 m (33 ft) or more into the tree by this method. The harvested bark is folded and carried in backpacks. [60] It can be stored for quite some time as mold does not grow on it, and is moistened before unfolding and working. It is then split lengthwise into the required width and woven or twisted into shape. Bark harvesting was mostly done by women, despite the danger of climbing ten meters in the air, because they were the primary makers of bark goods. [61]

Today bark rope making is a lost art in many communities, although it is still practiced for decoration or art in a few places. Other uses of bark are still common for artistic or practical purposes. In recent years there has been a revival of cedar weaving in some communities, and along with it, new forms of cedar bark products. For example, in some recent weddings cedar roses are used to decorate the tables.

Timber

Canadian western redcedar cowl in the National Assembly for Wales SeneddFunnel.jpg
Canadian western redcedar cowl in the National Assembly for Wales

The soft red-brown timber has a tight, straight grain and few knots. It is valued for its distinct appearance, aroma, and its high natural resistance to decay, being extensively used for outdoor construction in the form of posts, decking, shingles, and siding. [62] It is commonly used for the framing and longwood in lightweight sail boats and kayaks. In larger boats it is often used in sandwich construction between two layers of epoxy resin and/or fibreglass or similar products. Due to its light weight 390 to 400 kg/m3 (24 to 25 lb/cu ft) dried it is about 30% lighter than common boat building woods, such as mahogany. For its weight it is quite strong but can be brittle. It glues well with epoxy resin or resorcinol adhesive.

Its light weight, strength, and dark, warm sound make it a popular choice for guitar soundboards, particularly among European guitar builders such as Lowden and Furch.

Western redcedar wood is export-restricted in the United States. [63] The tree is highly allergenic and woodworkers or loggers who work with it may have adverse reactions, including the development of occupational asthma, exacerbation of existing asthma, reduction of lung function, and eye irritation. Approximately 5% of workers are allergic to western redcedar. The US Occupational Safety and Health Administration has set a permissible exposure limit for red cedar dust of 2.5 mg/m3 as a time-weighted average over eight hours. [64]

Essential oil

The essential oil of western redcedar leaves contains natural compounds, such as α-thujone, β-thujone, fenchone, sabinene, terpinen-4-ol and beyerene, [65] which have also been isolated from different other essential oils. Some of these substances are aroma compounds and are used in perfumery. [66] Thujones are GABAA receptor competitive antagonists however because of their high toxicity and convulsive activity they do not have any pharmacological use. [67]

Other uses

It is also widely used throughout Europe and America for making beehive components.

Its bark has been studied for applications in polyurethane. [68]

Notable specimens

The Quinault Lake Redcedar was the world's largest western redcedar. QuinaultLakeCedar 7274c.jpg
The Quinault Lake Redcedar was the world's largest western redcedar.

The largest living specimen is the Cheewhat Giant, in Pacific Rim National Park Reserve on Vancouver Island, at 450 cubic metres (15,870 cu ft). [69] The tallest known individual is the Willaby Creek Tree south of Lake Quinault, 59 m (195 ft) in height. [70] The 'Quinault Lake Redcedar' was the largest known western redcedar in the world, with a wood volume of 500 m3 (17,650 cu ft). Located near the northwest shore of Lake Quinault north of Aberdeen, Washington, about 34 kilometres (21 mi) from the Pacific Ocean, it was one-third the volume of the largest known tree, a giant sequoia named 'General Sherman'. The Quinault Lake Redcedar was 53 m (174 ft) tall with a diameter of 5.9 m (19.5 ft) at breast height. The Quinault Lake Redcedar was destroyed by a series of storms in 2014 and 2016 and is now only a glorified stump. [6] [71] The fifth-largest known was the Kalaloch Cedar in Olympic National Park, at 350 m3 (12,370 cu ft), [72] until it was destroyed by a storm in March 2014. [73]

A redcedar over 71 m (233 ft) tall, 4.5 m (15 ft) in diameter, and over 700 years old stood in Cathedral Grove on Vancouver Island before it was set on fire and destroyed by vandals in 1972. That tree now lies in "Giant's Grave", a self-dug 'grave' created by the force of its own impact. [74] A specimen measuring 5.5 m (18 ft) diameter and 54 m (177 ft) tall on the Giant Red Cedar National Recreation Trail in the Idaho Panhandle National Forests is designated the "Champion Tree of Idaho". [75]

The Giant Cedar Stump is an ancient redcedar turned roadside attraction in Snohomish County, Washington. [76]

See also

Related Research Articles

Douglas fir Species of tree

The Douglas fir is an evergreen conifer species in the pine family, Pinaceae. It is native to western North America and is also known as Douglas-fir, Douglas spruce, Oregon pine, and Columbian pine. There are three varieties: coast Douglas-fir, Rocky Mountain Douglas-fir and Mexican Douglas-fir.

<i>Cedrus</i> Genus of plants (coniferous trees)

Cedrus, common English name cedar, is a genus of coniferous trees in the plant family Pinaceae. They are native to the mountains of the western Himalayas and the Mediterranean region, occurring at altitudes of 1,500–3,200 m in the Himalayas and 1,000–2,200 m in the Mediterranean.

<i>Thuja</i> Genus of conifers

Thuja is a genus of coniferous trees or shrubs in the Cupressaceae. There are five species in the genus, two native to North America and three native to eastern Asia. The genus is monophyletic and sister to Thujopsis. Members are commonly known as arborvitaes, thujas or cedars.

<i>Chamaecyparis lawsoniana</i> Species of conifer

Chamaecyparis lawsoniana, known as Port Orford cedar or Lawson cypress, is a species of conifer in the genus Chamaecyparis, family Cupressaceae. It is native to Oregon and northwestern California, and grows from sea level up to 4,900 feet (1,500 m) in the valleys of the Klamath Mountains, often along streams.

<i>Callitropsis nootkatensis</i> Species of conifer

Callitropsis nootkatensis, formerly known as Cupressus nootkatensis is a species of trees in the cypress family native to the coastal regions of northwestern North America. This species goes by many common names including: Nootka cypress, yellow cypress, Alaska cypress, Nootka cedar, yellow cedar, Alaska cedar, and Alaska yellow cedar. The specific epithet "nootkatensis" is derived from its discovery by Europeans on the lands of a First Nation of Canada, those lands of the Nuu-chah-nulth people of Vancouver Island, British Columbia, who were formerly referred to as the Nootka.

<i>Alnus rubra</i> Species of tree

Alnus rubra, the red alder, is a deciduous broadleaf tree native to western North America.

<i>Thuja occidentalis</i> Species of evergreen coniferous tree

Thuja occidentalis, also known as northern white-cedar, eastern white-cedar, or arborvitae, is an evergreen coniferous tree, in the cypress family Cupressaceae, which is native to eastern Canada and much of the north-central and northeastern United States. It is widely cultivated as an ornamental plant.

<i>Platycladus</i> Genus of conifers

Platycladus is a monotypic genus of evergreen coniferous trees in the cypress family Cupressaceae, containing only one species, Platycladus orientalis, also known as Chinese thuja, Oriental arborvitae, Chinese arborvitae, biota or Oriental thuja. It is native to northeastern parts of East Asia and North Asia, but is also now naturalised as an introduced species in other regions of the Asian continent.

<i>Arbutus menziesii</i> Species of tree

Arbutus menziesii or Pacific madrone, is a species of broadleaf evergreen tree in the family Ericaceae, native to the western coastal areas of North America, from British Columbia to California.

<i>Tsuga heterophylla</i> Species of conifer

Tsuga heterophylla, the western hemlock or western hemlock-spruce, is a species of hemlock native to the west coast of North America, with its northwestern limit on the Kenai Peninsula, Alaska, and its southeastern limit in northern Sonoma County, California. The Latin species name means 'variable leaves'.

Cedar bark textile Wood-based textile of the indigenous peoples of the Pacific Northwest

Cedar bark textile was used by indigenous people in the Pacific Northwest region of modern-day Canada and the United States. Historically, most items of clothing were made of shredded and woven cedar bark.

<i>Calocedrus decurrens</i> Species of conifer

Calocedrus decurrens, with the common names incense cedar and California incense-cedar, is a species of coniferous tree native to western North America. It is the most widely known species in the genus, and is often simply called 'incense cedar' without the regional qualifier.

Management of Pacific Northwest riparian forests is necessary because many of these forests have been dramatically changed from their original makeup. The primary interest in riparian forest and aquatic ecosystems under the Northwest Forest Plan (NWFP) is the need to restore stream habitat for fish populations, particularly anadromous salmonids. Some of these forests have been grazed by cattle or other livestock. The heavy hooves of these animals compact the soil. This compaction does not allow the water to be absorbed into the ground, so the water runs off into the stream carrying topsoil along the way.

<i>Didymascella thujina</i> Species of fungus

Didymascella thujina is an ascomycete fungus in the family Helotiaceae. D. thujina causes cedar leaf blight, a leaf disease, on western red cedar and white cedar (T. occidentalis).

<i>Laminated root rot</i>

Laminated root rot also known as yellow ring rot is caused by the fungal pathogen Phellinus weirii. Laminated root rot is one of the most damaging root disease amongst conifers in northwestern America and true firs, Douglas fir, Mountain hemlock, and Western hemlock are highly susceptible to infection with P. weirii. A few species of plants such as Western white pine and Lodgepole pine are tolerant to the pathogen while Ponderosa pine is resistant to it. Only hardwoods are known to be immune to the pathogen.

Thujaplicin Chemical compound

Thujaplicins are a series of tropolone-related chemical substances that have been isolated from the hardwoods of the trees of Cupressaceae family. These compounds are known for their antibacterial, antifungal, and antioxidant properties. They were the first natural tropolones to be made synthetically.

Hinokitiol Chemical compound

Hinokitiol (β-thujaplicin) is a natural monoterpenoid found in the wood of trees in the family Cupressaceae. It is a tropolone derivative and one of the thujaplicins. Hinokitiol is used in oral and skin care products, and is a food additive used in Japan.

<i>Pseudotsuga menziesii <span style="font-style:normal;">var.</span> menziesii</i> Variety of conifer

Pseudotsuga menziesii var. menziesii, commonly known as Coast Douglas-fir, Pacific Douglas-fir, Oregon pine, or Douglas spruce, is an evergreen conifer native to western North America from west-central British Columbia, Canada southward to central California, United States. In Oregon and Washington its range is continuous from the Cascades crest west to the Pacific Coast Ranges and Pacific Ocean. In California, it is found in the Klamath and California Coast Ranges as far south as the Santa Lucia Mountains with a small stand as far south as the Purisima Hills, Santa Barbara County. In the Sierra Nevada it ranges as far south as the Yosemite region. It occurs from near sea level along the coast to 1,800 metres (5,900 ft) in the California Mountains. Further inland, coast Douglas-fir is replaced by Rocky Mountain or interior Douglas-fir. Interior Douglas-fir intergrades with coast Douglas-fir in the Cascades of northern Washington and southern British Columbia.

Cheewhat Giant, also known as the Cheewhat Lake Cedar, is a large western red cedar tree located within Pacific Rim National Park Reserve on Vancouver Island in British Columbia, Canada. It is the largest living Western redcedar, the largest known tree in Canada and one of the largest in the world.

Duncan Cedar

The Duncan Cedar, also known as the Duncan Memorial Cedar and the Nolan Creek Tree, is a large specimen of Western redcedar. The tree is located on the Olympic Peninsula in the U.S. state of Washington. It is currently the second largest known Western redcedar in the world, after the Cheewhat Giant on Canada's Vancouver Island.

References

  1. Farjon, A. (2013). "Thuja plicata". IUCN Red List of Threatened Species . 2013: e.T42263A2968155. doi: 10.2305/IUCN.UK.2013-1.RLTS.T42263A2968155.en . Retrieved 19 November 2021.
  2. 1 2 USDA, NRCS (n.d.). "Thuja plicata". The PLANTS Database (plants.usda.gov). Greensboro, North Carolina: National Plant Data Team. Retrieved 10 December 2015.
  3. "Thuja plicata". RHS. Retrieved 7 September 2021.
  4. "Thuja plicata". Germplasm Resources Information Network (GRIN). Agricultural Research Service (ARS), United States Department of Agriculture (USDA). Retrieved 11 December 2017.
  5. 1 2 3 4 5 6 7 8 9 10 11 12 Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977]. Northwest Trees: Identifying & Understanding the Region's Native Trees (field guide ed.). Seattle: Mountaineers Books. pp. 155–162. ISBN   1-68051-329-X. OCLC   1141235469.
  6. 1 2 3 4 5 6 Earle, Christopher J., ed. (2018). "Thuja plicata". The Gymnosperm Database.
  7. 1 2 3 4 5 Farjon 2005.
  8. 1 2 Stewart 1984, p. 24.
  9. Daniels, C. R.; Russell, J. H. (1 May 2007). "Analysis of Western Redcedar (Thuja plicata Donn) Heartwood Components by HPLC as a Possible Screening Tool for Trees with Enhanced Natural Durability". Journal of Chromatographic Science. 45 (5): 281–285. doi: 10.1093/chromsci/45.5.281 . PMID   17555638.
  10. Chan-Yeung, Moira (January 1994). "Mechanism of occupational asthma due to Western red cedar (Thuja plicata)". American Journal of Industrial Medicine. 25 (1): 13–18. doi:10.1002/ajim.4700250106. PMID   8116639.
  11. Gardner 1963, p. 21.
  12. 1 2 Chedgy, Lim & Breuil 2009.
  13. 1 2 3 Stewart 1984, p. 22.
  14. Morita, Yasuhiro; Matsumura, Eiko; Okabe, Toshihiro; Fukui, Toru; Shibata, Mitsunobu; Sugiura, Masaaki; Ohe, Tatsuhiko; Tsujibo, Hiroshi; Ishida, Nakao; Inamori, Yoshihiko (2004). "Biological Activity of α-Thujaplicin, the Isomer of Hinokitiol". Biological & Pharmaceutical Bulletin. 27 (6): 899–902. doi: 10.1248/bpb.27.899 . PMID   15187442.
  15. Vanitha, Thiraviam; Thammawong, Manasikan; Umehara, Hitomi; Nakamura, Nobutaka; Shiina, Takeo (December 2019). "Effect of hinokitiol impregnated sheets on shelf life and quality of "KEK‐1" tomatoes during storage". Packaging Technology and Science. 32 (12): 641–648. doi:10.1002/pts.2479. S2CID   202995336.
  16. Pietra, Francesco (August 1973). "Seven-membered conjugated carbo- and heterocyclic compounds and their homoconjugated analogs and metal complexes. Synthesis, biosynthesis, structure, and reactivity". Chemical Reviews. 73 (4): 293–364. doi:10.1021/cr60284a002.
  17. Saniewski, Marian; Horbowicz, Marcin; Kanlayanarat, Sirichai (10 September 2014). "The Biological Activities of Troponoids and Their Use in Agriculture A Review". Journal of Horticultural Research. 22 (1): 5–19. doi: 10.2478/johr-2014-0001 . S2CID   33834249.
  18. British Columbia Forests & Range Tree Book: Thuja plicata
  19. British Columbia Tree Species Compendium Western redcedar
  20. 1 2 Minore, Don (1990). "Thuja plicata". In Burns, Russell M.; Honkala, Barbara H. (eds.). Conifers. Silvics of North America. Washington, D.C.: United States Forest Service (USFS), United States Department of Agriculture (USDA). Vol. 1 via Southern Research Station.
  21. Tesky, Julie L. (1992). "Thuja plicata". Fire Effects Information System (FEIS). US Department of Agriculture (USDA), Forest Service (USFS), Rocky Mountain Research Station, Fire Sciences Laboratory.
  22. Flora of North America.
  23. Dictionary of Upriver Halkomelem, Volume II pp. 1605. Galloway, Brent Douglas
  24. Dictionary of Upriver Halkomelem, Volume I pp. 996. Galloway, Brent Douglas
  25. Stewart 1984, p. 21.
  26. Priestman, Lauren. "Plant Description: Thuja plicata/Western Red Cedar". Northern Rockies Natural History Guide. University of Montana, Missoula. Retrieved 21 July 2013.
  27. Flora of North America, p. 411.
  28. Hill 1985, p. 103.
  29. Skolmen, Roger G. (1974). "Natural Durability of Some Woods Used in Hawaii". Pacific Southwest Forest and Range Experiment Station. U.S. Forest Service. Retrieved 21 July 2013.
  30. "Thuja plicata". Interactive Flora of Northwest Europe.
  31. 1 2 3 4 5 "Thuja plicata". United States Forest Service . Retrieved 5 May 2021.
  32. Patterson, Patricia A. (1985). Field Guide to the Forest Plants of Northern Idaho (PDF). United States Forest Service. p. 25.
  33. Allen, Eric Andrew, 1955- (1996). Common tree diseases of British Columbia. Morrison, D. J., Wallis, G. W., Pacific Forestry Centre. Victoria, B.C.: Pacific Forestry Centre. ISBN   0-662-24870-8. OCLC   35976392.{{cite book}}: CS1 maint: multiple names: authors list (link)
  34. Thies, Walter G.; Sturrock, Rona N. (1995). "Laminated root rot in western North America". Gen. Tech. Rep. PNW-GTR-349. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 32 P. In Cooperation with: Natural Resources Canada, Canadian Forest Service, Pacific Forestry Centre. 349. doi: 10.2737/PNW-GTR-349 . hdl:2027/umn.31951d02889118b.
  35. Buckland, D. C. (1 October 1946). "Investigations of decay in western red cedar in british columbia". Canadian Journal of Research. 24c (5): 158–181. doi:10.1139/cjr46c-018. ISSN   1923-4287.
  36. Wood, David L. (2003). Pests of the Native California Conifers. Koerber, Thomas W., Scharpf, Robert F., Storer, Andrew J. Berkeley: University of California Press. ISBN   978-0-520-93637-9. OCLC   773564950.
  37. Minore, D. (1990). Western redcedar. In Silvics of North America vol.1: Conifers. (1990). Burns, R.M. & Honkala, B.H. (tech. Coords). Agriculture Handbook 654. USDA Forest Service: Washington DC.
  38. Bitner 2007, p. 424.
  39. "RHS Plant Selector - Thuja plicata 'Atrovirens'". RHS. Retrieved 5 March 2021.
  40. "RHS Plant Selector - Thuja plicata 'Aurea'". RHS. Retrieved 5 March 2021.
  41. "RHS Plant Selector - Thuja plicata 'Stoneham Gold'". RHS. Retrieved 5 March 2021.
  42. "RHS Plantfinder - Thuja plicata 'Whipcord'" . Retrieved 23 December 2018.
  43. "Thuja plicata 'Zebrina'". RHS. Retrieved 5 March 2021.
  44. Stewart 1984, pp. 17–19.
  45. Van Pelt 2001, p. 30.
  46. 1 2 3 Stewart 1984, p. 27.
  47. Stewart 1984, p. 26.
  48. 1 2 Stewart 1984, p. 36.
  49. Pritzker 1998, p. 292.
  50. Miller 2008, p. 67.
  51. DeCapua, pp. 16–20
  52. Stewart 1984, p. 39.
  53. Stewart 1984, pp. 37–38.
  54. Stewart 1984, p. 40.
  55. Stewart 1984, p. 42.
  56. Stewart 1984, p. 43.
  57. McNeese 2002, p. 43.
  58. Dill 2006, pp. 127–128.
  59. Stewart 1984, p. 116.
  60. Stewart 1984, p. 115.
  61. Stewart 1984, p. 113.
  62. Chase, Jeri (Fall 2008). "Western Redcedar, "Tree of Life"" (PDF). Forests for Oregon. Oregon Department of Forestry. pp. 18–19. Retrieved 18 September 2014.
  63. "5 Things You Would Never Expect Need an Export License". The Export Compliance Journal. 6 June 2016. Retrieved 12 March 2022.
  64. "Wood Dust". OSHA/NIOSH. 28 September 2011.
  65. Lis, Anna; Swaczyna, Agata; Krajewska, Agnieszka; Mellor, Karolina (July 2019). "Chemical Composition of the Essential Oils From Twigs, Leaves, and Cones of Thuja plicata and Its Cultivar Varieties "Fastigiata", "Kornik," and "Zebrina"". Natural Product Communications. 14 (7): 1934578X1986290. doi: 10.1177/1934578X19862904 . S2CID   202164043.
  66. Fahlbusch, Karl-Georg; Hammerschmidt, Franz-Josef; Panten, Johannes; Pickenhagen, Wilhelm; Schatkowski, Dietmar; Bauer, Kurt; Garbe, Dorothea; Surburg, Horst (15 January 2003). "Flavors and Fragrances". Ullmann's Encyclopedia of Industrial Chemistry: a11_141. doi:10.1002/14356007.a11_141. ISBN   3527306730.
  67. Olsen, R. W. (25 April 2000). "Absinthe and gamma -aminobutyric acid receptors". Proceedings of the National Academy of Sciences. 97 (9): 4417–4418. Bibcode:2000PNAS...97.4417O. doi: 10.1073/pnas.97.9.4417 . PMC   34311 . PMID   10781032.
  68. Chen, Heyu. "The Utilization of Bark and Bark Components from Western Red Cedar (Thuja plicata) for Polyurethane Applications" (PDF).{{cite web}}: CS1 maint: url-status (link)
  69. Van Pelt 2001, p. 34.
  70. Van Pelt 2001, p. 36.
  71. Van Pelt 2001, p. 32.
  72. Van Pelt 2001, p. 37.
  73. Exotic Hikes, "Olympic National Park’s Kalaloch Cedar Destroyed by Storm"
  74. Picture of the Cathedral Grove stump.
  75. "Idaho Giant Red Cedar - NRT Database".
  76. Dorpat, Paul (27 October 2016). "This tunneled tree stump in Snohomish County was an early drive-through attraction". The Seattle Times. Retrieved 31 May 2022. Variously named the Giant Cedar Stump, the Arlington Stump or just The Stump, this Snohomish County roadside attraction began, of course, as a tree, which was killed by fire in 1893; reduced to stump size and tunneled in 1916; given a concrete base in 1922; and moved alongside the new Highway 99 in 1939, where it is shown here (in 1940). The stump moved in 1971 to its current home, at the Smokey Point Rest Area at milepost 207 off Interstate 5.

Works cited