Quercus langbianensis

Common Names

Soi Lang Bian, Soi Dong Nai, Soi Bao Loc, Soi Ba Na, Soi Camus, Soi Gui, Gui, Fa Dou Qing Gang, Ulayan

Summary

Native to southeastern Vietnam, Cambodia, and parts of southeastern China (SE Yunnan), this evergreen oak grows to about 15 m and is distinguished by leathery elliptic-lanceolate leaves (7–14 cm long, 2.5–4 cm wide) with a glossy green upper surface and glabrous lower surface, 7–13 secondary nerves, and cupules that are cup-shaped with 5–7 rings enclosing subglobose acorns about 1.7 cm long; infructescence around 2 cm, bracts with 5–7 rings, and a habitat of dense broadleaf evergreen forests at elevations roughly 1400–2000 m. It belongs to subgenus Cyclobalanopsis in the Fagaceae and is characteristic of montane tropical forests in its native range.

Practical considerations include its montane, wet forest origin and a typical height near 15 m, indicating space and climate similar to its native habitat; not hardy, suggesting limited cold tolerance in cultivation. The acorns have edible kernels, which provides a notable edible attribute of the seeds.

Lifecycle

Perennial

Height

49 ft-49 ft 2 in

Hardiness Zones

Not hardy

Soil Type

Clayey, wet, peaty soil

Soil Drainage

Wet, peaty soils

Foliage Color

Green with a shiny upper surface and a glaucous underside.

Fall Foliage Color

Green

Leaf Lifecycle

Evergreen broadleaf

Growth Rate

7-10 m usually; up to 25-28 m

Seasons of Interest

Fall