Scientific name Quercus glauca Rank Species | Genus Quercus Higher classification Oak | |
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Similar Quercus myrsinifolia, Cyclobalanopsis, Fagaceae, Quercus acuta, Oak |
Quercus glauca (syn. Cyclobalanopsis glauca), also known as ring-cupped oak, Japanese blue oak or glaucous-leaf oak, is an Asian species in the genus Quercus in the beech family. It is native to eastern and southern Asia, mostly in China but also in neighboring countries (Afghanistan, Kashmir, northern and eastern India, Nepal, Bhutan, Myanmar, Vietnam, Korea, and southern Japan).

Quercus glauca is a small to medium-sized evergreen broadleaf tree growing to 15–20 m tall. The leaves are a distinct deep purple-crimson on new growth, soon turning glossy green above, glaucous blue-green below, 6–13 cm long and 2–5 cm broad, with a serrated margin. The flowers are catkins, and the fruit are acorns 1–1.6 cm long, with series of concentric rings on the outside of the acorn cup.

Cultivation and uses
It is planted as an ornamental tree in regions of Europe and North America with mild winters.

