| Quercus helferiana | |
| Author | A.DC 1864 Prodr. 16(2): 101 |
| Synonyms | Cyclobalanopsis
helferiana ( A.DC) Oersted 1867 ilex Lour. 1790 nom. illeg. prainiana H.Lév. 1913 |
| Local names | mao zhi qing gang |
| Range | India; Laos;
Thailand; Vietnam; Myanmar; China (Guangdong, Guangxi, South Guizhou,
South Yunnan); 900 to 2000 m; |
| Growth habit | reaches 20 m
tall, but often stunted in exposed sites; trunk reaches 1 m in circumference;
|
| Leaves | 12-20 x 4-9
cm; evergreen; oblong-elliptic, oval or elliptic-lanceolate; young leaves
densely tomentose; apex acuminate to obtuse, base rounded or broadly cuneate;
margin crenate in the apical half; adaxially smooth, shiny, glabrous except
at the base of the midrib; grey brown tomentose beneath, with persistent
fasciate hairs; midvein impressed adaxially; 9-14 vein pairs, raised below,
slightly impressed above ; stout petiole 1-2(-3) cm long, pale brown tomentose,
glabrescent; |
| Flowers | March-April; female on many-flowered spikes as long as the petiole; 5-6 short styles, staminodes sometimes present; |
| Fruits | acorn flattened
1-1.6 cm long, 1.5-2.2 cm wide; mucronate; flat or sometimes depressed,
1.2-1.4 cm wide basal scar ; enclosed 1/2 by cup; cup flat (5-6 mm long,
2-2.5 cm wide) and thick (1.2-2 mm), with 8-10 concentric rings of minutely,
golden tomentose scales, remotely denticulate; maturing in 1 year; |
|
Bark, twigs and |
bark
very rough, brown, with thick ridges; young twigs rusty tomentose, becoming
glabrous when 3 years old; |
| Hardiness zone, habitat | not hardy; tropical forests; |
| Miscellaneous | --
A. Camus : n° 68; -- Sub-genus Cerris, Section Cyclobalanopsis; -- Section Helferiana, sub-section Helferianae (Menitsky); |
| Subspecies and varieties |
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| Pictures |
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