''Thuja koraiensis'', also called Korean arborvitae, is a species of ''

Thuja ''Thuja'' ( ) is a genus of coniferous tree or shrub in the Cupressaceae (cypress family). 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''. M ...

'', native to

Korea Korea ( ko, 한국, or , ) is a peninsular region in East Asia. Since 1945, it has been divided at or near the 38th parallel, with North Korea (Democratic People's Republic of Korea) comprising its northern half and South Korea (Republic o ...

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 South Korea, officially the Republic of Korea (ROK), is a country in East Asia, constituting the southern part of the Korean Peninsula and sharing a land border with North Korea. Its western border is formed by the Yellow Sea, while its eas ...

, but most of the species' range in

North Korea North Korea, officially the Democratic People's Republic of Korea (DPRK), is a country in East Asia. It constitutes the northern half of the Korean Peninsula and shares borders with China and Russia to the north, at the Yalu (Amnok) and T ...

is unprotected and threatened by

habitat loss Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

.Farjon, A. (2005). ''Monograph of Cupressaceae and Sciadopitys''. Royal Botanic Gardens, Kew. It is an

evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, whic ...

shrub or small

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...

growing to 3–10 m tall. The foliage forms flat sprays with scale-like leaves 2–4 mm long (up to 15 mm long on strong-growing shoots), matt dark green above, and with broad, vivid white stomatal wax bands below. The

cones A cone is a three-dimensional geometric shape that tapers smoothly from a flat base (frequently, though not necessarily, circular) to a point called the apex or vertex. A cone is formed by a set of line segments, half-lines, or lines conn ...

are oval, yellow-green ripening red-brown, 7–11 mm long and 4–5 mm broad (opening to 6–9 mm broad), with 8-12 overlapping scales. It is occasionally grown as an ornamental tree for the contrast between the green upper and bright white lower sides of the foliage, though planting is limited by the low availability of seeds.

References

Koraiensis Trees of Korea Trees of China Vulnerable flora of Asia Taxa named by Takenoshin Nakai Taxonomy articles created by Polbot Plants described in 1919 {{conifer-stub