Quercus aliena

Quercus aliena, the galcham oak or oriental white oak, is a species of oak in the family Fagaceae, in the white oak section Quercus.

Description
It is a deciduous tree growing to 30 m tall with a trunk up to 1 m in diameter with fissured gray-brown bark. The leaves are obovate to oblong, glabrous above, glabrous to densely grey-white hairy below, mostly 10 – long and 5 – wide (rarely up to 30 cm long and 16 cm wide), with 9 to 15 lobes on each side, and a 10 – petiole.

The flowers monecious catkins. The acorns are 17 – long and 13 – wide, a third to a half enclosed in a green-grey cup on a short peduncle; they are solitary or 2–3 together, and mature in about six months from pollination. A long-lived tree, it is slow-growing.

Taxonomy
Three to five varieties are accepted:
 * Quercus aliena var. aliena. Leaf margin wavy; leaf greyish below.
 * Quercus aliena var. acutiserrata Maxim. Leaf margin serrated, with sharp serration; leaf densely hairy below with greyish hairs.
 * Quercus aliena var. pekingensis Schottky. Leaf margin serrated, with rounded serration; leaf glabrous or only slightly hairy below.
 * Quercus aliena var. alticupulifirmis H.Wei Jen & L.M.Wang (not accepted by Flora of China).
 * Quercus aliena var. pellucida Blume (not accepted by Flora of China).

Hybrids between Quercus aliena and several other oaks in Quercus sect. Quercus are known.

Common names
In China it is called ruìchí húlì, or húlì. Quercus aliena var. acutiserrata is referred to as ruìchí húlì, while var. aliena is referred to as húlì. In Japan it is called naragashiwa.

Distribution
It is native to East Asian states of Korea, Japan (where it occurs in Honshu, Shikoku, and Kyushu), mainland China (where it occurs in the provinces of Anhui, Gansu, Guangdong, Guangxi, Guizhou, Hebei, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Liaoning, Shaanxi, Shandong, Shanxi, Sichuan, Yunnan, and Zhejiang) and Taiwan.

Cultivation and uses
The wood is used in East Asia for boat building and wood flooring for houses. The seeds can be crushed into a powder and used as a soup thickener and for mixing into cereals and breads. The seeds when roasted can also be used as a substitute for coffee. Galls produced by the larvae of insects are a rich source of tannin.

Quercus aliena was introduced to Europe in 1908, but remains rare in cultivation outside of its native area. The taproot is deep, making older plants difficult to move. It grows in full sun or partial shade and tolerates strong winds. It can grow in almost any type of soil as long as not waterlogged.