Quercus 櫟屬
型態特徵
Evergreen or deciduous trees, rarely shrubs, monoecious; buds with many imbricate scales, ellipsoid or 4-angular-ellipsoid; scales hairy or glabrous. Leaves atternate short-petiolate or subsessile, margins echinate, serrate, dentate, wavy, lobed, pinnatifid or entire. Flowers in axiilary catkins or spikes, the catkins or spikes often collected into terrminal panicles or corymbs; staminate catkins slender, erect or pendulous; staminate flowers sessile or nearly so; perianth 4–7-lobed, -cleft or -parted, lobes mostly imbricate, hairy or glabrous outside, nearly glabrous inside; stamens usually 4–7 (2–12), anthers almost glabrous, or densely to sparsely hairy. Pistillate flowers solitary or rarely a few together in spikes, each subtended by 1–2 bracteoles, sometimes pedicelled; perianth 4–6-lobed, urceolate; ovary 3 (1–5)-celled, ovules 2 in each cell, styles 3 (1–5), short or elongate-cylindrical, stigma capitate, or enlarged and flat or rarely pointed. Fruit a nut, usually solitary, partially enclosed by a cupule, subgolbose, globose or ellipsoid, with thin pericarp; cupules cup-shaped, scales numerous, imbricate flat, angled or spreading and triangular, lanceolate or linear, densely or loosely arranged; seed germination hypogeal.
More than 100 species in the temperate regions of the northern hemisphere and in the tropics at high altitudes; as far south as Colombia in South America and the Malay Archipelago in Asia; nine species with one varieties, including introduced taxa, in Taiwan.
種列表
- Quercus acutissima 麻櫟
- Quercus aliena 大槲樹
- Quercus dentata 槲樹
- Quercus glandulifera var. brevipetiolata 思茅櫧櫟
- Quercus microphylla
- Quercus phanera
- Quercus phillyrioides 姥芽櫟
- Quercus sp.
- Quercus spinosa 高山櫟
- Quercus suber 西班牙栓皮櫟
- Quercus tarokoensis 太魯閣櫟
- Quercus tatakaensis 銳葉高山櫟
- Quercus variabilis 栓皮櫟
- Quercus × takaoyamensis
