Thuja occidentalis

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Thuja occidentalis
Thuja occidentalis.jpg
Leaves and immature cones
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Gymnospermae
Division: Pinophyta
Class: Pinopsida
Order: Cupressales
Family: Cupressaceae
Genus: Thuja
T. occidentalis
Binomial name
Thuja occidentalis
Thuja occidentalis range map.png
Natural range

Thuja occidentalis, also known as northern white-cedar, [1] eastern white-cedar, [2] or arborvitae, [2] [3] 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. [3] [4] It is widely cultivated as an ornamental plant. It is not to be confused with Juniperus virginiana (eastern red cedar).


Common names

Its additional common names include swamp cedar, [3] American arborvitae, [4] and eastern arborvitae. [4] The name arborvitae is particularly used in the horticultural trade in the United States; it is Latin for 'tree of life' – due to the supposed medicinal properties of the sap, bark, and twigs. [5] It is sometimes called white-cedar (hyphenated) or whitecedar (one word) [4] to distinguish it from Cedrus , the true cedars. [6]


Unlike the closely related western red cedar (Thuja plicata), northern white cedar is only a small or medium-sized tree, growing to a height of 15 m (49 ft) tall with a 0.9 m (3.0 ft) trunk diameter, exceptionally to 38 metres (125 ft) tall and 1.8 metres (5.9 ft) diameter. [7] The tree is often stunted or prostrate in less favorable locations. The bark is red-brown, furrowed and peels in narrow, longitudinal strips. Northern white cedar has fan-like branches and scaly leaves. The foliage forms in flat sprays with scale-like leaves 3–5 millimetres (18316 in) long.

The seed cones are slender, yellow-green, ripening to brown, 9–14 millimetres (38916 in) long and 4–5 millimetres (532316 in) broad,[ citation needed ] with six to eight overlapping scales. They contain about eight seeds each. [7] The branches may take root if the tree falls. [4]


The species was first described by Carl Linnaeus in 1753. Over 30 synonyms are listed in Kew's Plants of the World Online database. [8]


Northern white cedar is native to an area in the southern part of eastern Canada and the adjacent part of the northern United States. It extends from southeastern Manitoba east throughout the Great Lakes region and into Ontario, Québec, New York, Vermont, New Hampshire, Maine, Prince Edward Island, New Brunswick, and Nova Scotia. Isolated populations occur in west-central Manitoba, and to the south in Massachusetts, Connecticut, Ohio, and Illinois and in the Appalachian Mountains of Kentucky, Tennessee, North Carolina, Pennsylvania, Maryland, Virginia, and West Virginia. [4] In Canada, its range reaches the Arctic treeline and the southern tip of Hudson Bay. It grows mainly in places with cooler summers, with a typical temperature of 16 to 22 °C (61 to 72 °F) in July, and a shorter growing season, from 90 to 180 days. [9]


A swamp along the Superior Hiking Trail in November with smattering of evergreen white cedars (left) and other trees and shrubs Superior Hiking Trail boardwalk.jpg
A swamp along the Superior Hiking Trail in November with smattering of evergreen white cedars (left) and other trees and shrubs

Northern white cedar grows naturally in wet forests, being particularly abundant in coniferous swamps, where other larger and faster-growing trees cannot compete successfully. It also occurs on other sites with reduced tree competition, such as cliffs. Although not currently listed as endangered, wild white cedar populations are threatened in many areas by high deer numbers; deer find the soft evergreen foliage a very attractive winter food and strip it rapidly. The largest known specimen is 34 m (112 ft) tall and 175 cm (69 in) diameter, on South Manitou Island within Leelanau County, Michigan.[ citation needed ] Northern white cedars can be very long-lived trees in certain conditions, with notably old specimens growing on cliffs where they are inaccessible to deer and wildfire. As of 2008, the oldest known living specimen was 1,141 years old, [10] but a dead specimen with 1,653 growth rings has been found. [11] Despite their age, these very old trees are small and stunted due to the difficult growing conditions. These individuals' long lifespans have been attributed to their slow growth and their ability to survive when different sections of the tree are damaged or killed. [12] The Witch Tree, a T. occidentalis growing out of a cliff face on Lake Superior in Minnesota, was described by the French explorer Sieur de la Verendrye as being a mature tree in 1731; it is still alive today.

Old trees growing on a rock ledge in Potawatomi State Park, Wisconsin Something out of nothing 2.jpg
Old trees growing on a rock ledge in Potawatomi State Park, Wisconsin

Specimens found growing on cliff faces in southern Ontario are the oldest trees in Eastern North America and all of Canada, having achieved ages in excess of 1,653 years. [4]


Thuja occidentalis is commercially used for rustic fencing and posts, lumber, poles, shingles, and in the construction of log cabins. [9] It is the preferred wood for the structural elements, such as ribs and planking, of birchbark canoes and the planking of wooden canoes. [13]

The essential oil within the plant has been used for cleansers, disinfectants, hair preparations, insecticides, liniment, room sprays, and soft soaps. The Ojibwa reportedly made a soup from the inner bark of the soft twigs. Others have used the twigs to make teas to relieve constipation and headache. [13]

Eastern white cedar – as arborvitae – is a popular ornamental plant used in both residential and commercial landscapes.

Thuja occidentalis has important uses in traditional Ojibwe culture. Honoured with the name Nookomis Giizhik (Grandmother Cedar), the tree is the subject of sacred legends and is considered a gift to humanity for its myriad of uses, among them crafts, construction, and medicine. [14] It is one of the four plants of the Ojibwe medicine wheel, associated with the north. The foliage is rich in vitamin C and is believed to be the annedda, which cured the scurvy of Jacques Cartier and his party in the winter of 1535–1536. [9] Due to the presence of the neurotoxic compound thujone, internal use can be harmful if used for prolonged periods or while pregnant.[ citation needed ]


A grove of a columnar ornamental variety in Powsin Botanical Garden, Warsaw, Poland Poland. Warsaw. Powsin. Botanical Garden 097.jpg
A grove of a columnar ornamental variety in Powsin Botanical Garden, Warsaw, Poland

T. occidentalis is widely used as an ornamental tree, particularly for screens and hedges, in gardens, parks, and cemeteries. Over 300 cultivars exist, showing great variation in colour, shape, and size, with some of the more common ones being 'Degroot's Spire', 'Ellwangeriana', 'Hetz Wintergreen', 'Lutea', 'Rheingold', 'Smaragd' (or 'Emerald Green'), 'Techny', and 'Wareana'. It was introduced into Europe as early as 1540.[ citation needed ] These cultivars have gained the Royal Horticultural Society's Award of Garden Merit:

See also

Related Research Articles

<i>Thuja</i> Genus of conifers

Thuja is a genus of coniferous tree or shrub 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>Picea mariana</i> North American species of spruce tree

Picea mariana, the black spruce, is a North American species of spruce tree in the pine family. It is widespread across Canada, found in all 10 provinces and all 3 territories. It is the official tree of the province of Newfoundland and Labrador and is that province's most numerous tree. The range of the black spruce extends into northern parts of the United States: in Alaska, the Great Lakes region, and the upper Northeast. It is a frequent part of the biome known as taiga or boreal forest.

<i>Cryptomeria</i> Species of conifer in the family Cupressaceae

Cryptomeria is a monotypic genus of conifer in the cypress family Cupressaceae, formerly belonging to the family Taxodiaceae. It includes only one species, Cryptomeria japonica. It used to be considered by some to be endemic to Japan, where it is known as Sugi. The tree is called Japanese cedar or Japanese redwood in English. It has been extensively introduced and cultivated for wood production on the Azores.

<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 tree 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, the Nuu-chah-nulth people of Vancouver Island, British Columbia, who were formerly referred to as the Nootka.

<i>Thuja plicata</i> Species of conifer

Thuja plicata is a large evergreen coniferous tree in the family Cupressaceae, native to the Pacific Northwest of North America. Its common name is western redcedar in the U.S. or western red cedar in the UK, and it is also called pacific red cedar, giant arborvitae, western arborvitae, just cedar, giant cedar, or shinglewood. It is not a true cedar of the genus Cedrus. T. plicata is the largest species in the genus Thuja, growing up to 70 metres (230 ft) tall and 7 metres (23 ft) in diameter. It mostly grows in areas that experience a mild climate with plentiful rainfall, although it is sometimes present in drier areas on sites where water is available year-round, such as wet valley bottoms and mountain streamsides. The species is shade-tolerant and able to establish in forest understories and is thus considered a climax species. It is a very long-lived tree, with some specimens reaching ages of well over 1,000 years.

<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>Abies nordmanniana</i> Species of conifer tree

Abies nordmanniana, the Nordmann fir or Caucasian fir, is a fir indigenous to the mountains south and east of the Black Sea, in Turkey, Georgia and the Russian Caucasus. It occurs at altitudes of 900–2,200 m on mountains with precipitation of over 1,000 mm.

<i>Juniperus chinensis</i> Species of conifer

Juniperus chinensis, the Chinese juniper is a species of plant in the cypress family Cupressaceae, native to China, Myanmar, Japan, Korea and the Russian Far East. Growing 1–20 metres tall, it is a very variable coniferous evergreen tree or shrub.

White cedar may refer to several different trees:

<span class="mw-page-title-main">Western larch</span> Species of conifer

The western larch is a species of larch native to the mountains of western North America ; in Canada in southeastern British Columbia and southwestern Alberta, and in the United States in eastern Washington, eastern Oregon, northern Idaho, and western Montana. It is the most productive of the three species of larch native to North America.

<i>Cornus alba</i> Species of flowering plant

Cornus alba, the red-barked, white or Siberian dogwood, is a species of flowering plant in the family Cornaceae, native to Siberia, northern China and Korea. It is a large deciduous surculose (suckering) shrub that can be grown as a small tree. As a popular ornamental used in landscaping its notable features include the red stems in fall (autumn) through late winter, bright winter bark; and the variegated foliage in some cultivars, such as C. alba 'Elegantissima'. C. alba can grow to 3 m (10 ft) high, but variegated forms are less vigorous. For the brightest winter bark, young shoots are encouraged by cutting to the ground some older stems at the end of the winter, before leaves are open. The oval fruits are white, sometimes tinted blue.

<i>Cupressus cashmeriana</i> Species of conifer

Cupressus cashmeriana, the Bhutan cypress or Kashmir cypress, is a species of evergreen conifer native to the eastern Himalaya in Bhutan and adjacent areas of Arunachal Pradesh in northeastern India. [ Now in vulnerable category, IUCN list retrieved in 2006 ]. It is also introduced in China and Nepal. It grows at moderately high altitudes of 1,250–2,800 metres (4,100–9,190 ft).

<i>Thuja koraiensis</i> Species of conifer

Thuja koraiensis, also called Korean arborvitae, is a species of Thuja, native to Korea and the extreme northeast of China (Changbaishan). Its current status is poorly known; the small population in China is protected in the Changbaishan Nature Reserve, as is the small population in Soraksan Nature Reserve in northern South Korea, but most of the species' range in North Korea is unprotected and threatened by habitat loss.

<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).

<span class="mw-page-title-main">Coniferous swamp</span> Forested wetlands dominated by conifers

Coniferous swamps are forested wetlands in which the dominant trees are lowland conifers such as northern white cedar. The soil in these swamp areas is typically saturated for most of the growing season and is occasionally inundated by seasonal storms or by winter snow melt.

<i>Acer palmatum</i> Species of maple

Acer palmatum, commonly known as Japanese maple, palmate maple, or smooth Japanese maple (Korean: danpungnamu, 단풍나무, Japanese: irohamomiji, イロハモミジ, or momiji,, is a species of woody plant native to Korea, Japan, China, eastern Mongolia, and southeast Russia. Many different cultivars of this maple have been selected and they are grown worldwide for their large variety of attractive forms, leaf shapes, and spectacular colors.

<i>Phormium</i> Genus of flowering plants in the family Asphodelaceae

Phormium is a genus of two plant species in the family Asphodelaceae. One species is endemic to New Zealand and the other is native to New Zealand and Norfolk Island. The two species are widely known in New Zealand as flax or their Māori names wharariki and harakeke respectively, and elsewhere as New Zealand flax or flax lily, but they are not closely related to the Northern Hemisphere's flax, which is native to the region extending from the eastern Mediterranean to India and has been used by humans since 30,000 B.C.

T. occidentalis may refer to several different species. The specific epithet occidentalis means 'western.'


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