''Quercus helferiana'' is a species of tree in the family

Fagaceae The Fagaceae are a family of flowering plants that includes beeches, chestnuts and oaks, and comprises eight genera with about 927 species. Fagaceae in temperate regions are mostly deciduous, whereas in the tropics, many species occur as evergre ...

and the " ring-cupped oak" sub-genus. It is native to Vietnam, Thailand, Laos, Myanmar, India (

northeast The points of the compass are a set of horizontal, radially arrayed compass directions (or azimuths) used in navigation and cartography. A compass rose is primarily composed of four cardinal directions—north, east, south, and west—each se ...

), and southern China (

Yunnan Yunnan , () is a landlocked Provinces of China, province in Southwest China, 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 ...

Guangdong Guangdong (, ), alternatively romanized as Canton or Kwangtung, is a coastal province in South China on the north shore of the South China Sea. The capital of the province is Guangzhou. With a population of 126.01 million (as of 2020) ...

Guangxi Guangxi (; ; Chinese postal romanization, alternately romanized as Kwanghsi; ; za, Gvangjsih, italics=yes), officially the Guangxi Zhuang Autonomous Region (GZAR), is an Autonomous regions of China, autonomous region of the People's Republic ...

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 t ...

Description

''Quercus helferiana'' is a tree up to 20 m. tall, with a trunk up to 0.3 m in diameter. Leaves oblong-elliptic, to elliptic-lanceolate, 120-150 (up to 220) × 40-80 (up to 95) mm, with wavy edges but no teeth or lobes.Flora of China, ''Cyclobalanopsis helferiana'' (A. de Candolle) Oersted, 1867, 毛枝青冈 mao zhi qing gang
/ref> The

acorn The acorn, or oaknut, is the nut of the oaks and their close relatives (genera ''Quercus'' and '' Lithocarpus'', in the family Fagaceae). It usually contains one seed (occasionally two seeds), enclosed in a tough, leathery shell, and borne ...

oblate In Christianity (especially in the Roman Catholic, Orthodox, Anglican and Methodist traditions), an oblate is a person who is specifically dedicated to God or to God's service. Oblates are individuals, either laypersons or clergy, normally livi ...

, 10-16 × 15–22 mm, grey, with a depressed apex and often covered with shaggy hairs; the scar is 12–14 mm in diameter, flat to concave at maturity. Flowering is in March–April, acorns found from October–November.

References

helferiana Flora of China Flora of Assam (region) Flora of Indo-China Plants described in 1864 {{Quercus-stub