Thuja occidentalis

Thuja occidentalis, also known as Eastern Arborvitae, Northern White-cedar, or American Arborvitae, is a species of Thuja, an evergreen tree in the cypress family Cupressaceae. Native to eastern North America, it is widely cultivated for its timber and ornamental value.

Description

Thuja occidentalis is a small to medium-sized tree, typically growing to a height of 10–20 meters. The bark is red-brown, furrowed and peels in narrow, longitudinal strips. The foliage forms in flat sprays with scale-like leaves. The tree is evergreen, with leaves that are dark green on top and light green beneath.

Distribution and Habitat

Thuja occidentalis is native to northeastern parts of the United States and southeastern parts of Canada. It is most commonly found 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.

Uses

The wood of Thuja occidentalis is light, soft and aromatic. It can be easily split and resists decay. Its uses have included making shingles, posts, and small objects where resistance to weather and insects is important, and for railroad ties. The wood and foliage, which contain thujone, are known to be toxic if consumed in large amounts.

In horticulture, Thuja occidentalis is widely used as an ornamental tree, particularly for screens and hedges, in urban and suburban landscapes. Its potential height, form, and scale-like leaves make it a unique and attractive tree for many types of landscapes.

Medicinal Use

In traditional medicine, Thuja occidentalis has been used for treatment of bronchial catarrh, enuresis, and skin disorders. Extracts of its foliage, bark and roots have been used in the traditional medicine of Native Americans.

Conservation

While Thuja occidentalis is not currently considered globally threatened, it is facing significant threats in its habitat due to habitat destruction, over-exploitation, and climate change.

See Also

• List of Thuja species
• Cupressaceae
• Coniferous Trees