''Keteleeria davidiana'' ( zh: 铁坚油杉) is a coniferous

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 ...

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 ...

native to

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia, at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the nort ...

and southeast China, in the provinces of Gansu, Guangxi,

Guizhou Guizhou (; formerly Kweichow) is a landlocked province in the southwest region of the People's Republic of China. Its capital and largest city is Guiyang, in the center of the province. Guizhou borders the autonomous region of Guangxi to the ...

Hubei Hubei (; ; alternately Hupeh) is a landlocked province of the People's Republic of China, and is part of the Central China region. The name of the province means "north of the lake", referring to its position north of Dongting Lake. The ...

Hunan Hunan (, ; ) is a landlocked province of the People's Republic of China, part of the South Central China region. Located in the middle reaches of the Yangtze watershed, it borders the province-level divisions of Hubei to the north, Jiangxi ...

Shaanxi Shaanxi (alternatively Shensi, see § Name) is a landlocked province of China. Officially part of Northwest China, it borders the province-level divisions of Shanxi (NE, E), Henan (E), Hubei (SE), Chongqing (S), Sichuan (SW), Gansu (W), N ...

Sichuan Sichuan (; zh, c=, labels=no, ; zh, p=Sìchuān; alternatively romanized as Szechuan or Szechwan; formerly also referred to as "West China" or "Western China" by Protestant missions) is a province in Southwest China occupying most of the ...

, and

Yunnan Yunnan , () is a landlocked province in the southwest of the People's Republic of China. The province spans approximately and has a population of 48.3 million (as of 2018). The capital of the province is Kunming. The province borders the C ...

. It also occurs in the very northern part of Vietnam. The tree is restricted to hills, mountains, and valleys at elevations of 200–1500 m. Generally, it grows in regions with a more continental climate than the other two ''Keteleeria'' species. The tree reaches 40–50 m in height, developing an irregular oblate crown with large branches. The branchlets have a dense covering of stiff hairs. The bark is dull brown to dark gray-black, and is scaly or flaky. The leaves are needle-like, 2-6.4 cm long by 3.6-4.2 mm broad. They are flat, stiff, and dark shiny green. 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 light brown, cylindrical, and stand erect on the branches. They are 8–20 cm long and 4–5 cm broad with a stalk 2.5-3.2 cm long. The winged oblong

seed A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...

s, which mature in October or November, are 13 mm long with a glossy brown wing 12–19 mm long. Three varieties of the species exist: *''Keteleeria davidiana'' var. ''calcarea''. Guangxi and Guizhou on calcareous mountains. First-year branchlets yellow. Apices of seed scales blunt and rounded. Winter buds globular. *''Keteleeria davidiana'' var. ''davidiana''. First-year branchlets yellow-gray or light-gray. Apices of seed scales narrowed. Winter buds ovoid. *''Keteleeria davidiana'' var. ''formosana''. Endemic on Taiwan, at 300–900 m. Dark leaf scars protruding noticeably on branches. Leaves 2–4 cm long. The wood is soft and white yellow, and is used for construction, bridges, furniture, and wood fiber.

References

External links

Gymnosperm DatabaseFlora of China
{{Taxonbar, from=Q137004 Pinaceae Least concern plants Trees of Taiwan Trees of Vietnam Trees of China