Frigid zone, temperate, and sub-tropical. Cosmopolitan, except tropical South America and tropical and South Africa.
Floral characters
The Flowers are inconspicuous, unisexual and reduced, staminate flowers are solitary, in catkins or heads, pistillate flowers are solitary or few in clusters · Male flowers: A 4-7 lobed perianth of tepals and 4-40 stamens and are usually grouped in pendulous catkins Female Flowers: Solitary or in small clusters. They have a 4-6 lobed perianth of tepals, and are often subtended by a series of bracteoles comprising an involucre. The single compound pistil of 3-6 carpels has an inferior ovary with 3-6 locules and two basal or nearly basal ovules in each locule. · Flower formule:
Leaf characters
Alternate, spiral or distichious · Simple, often lobed medium-sized leaves, often leathery, sometimes herbaceous, petiolate · cadocious stipules, leaves ervergreen or decidious
Stipules
present
Fruit characters
The fruit is usually a 1-seeded nut (with stony or leathery pericarp) that is basally enveloped by a cupule derived from the involucre. Rarely it's a samara. In the cupule of Quercus is only one nut, Fagus has two and Castanea three. The seeds are non-endospermic but they contain starch. 2 Cotyledons, a achlorophyllous embryo.
Glands
present
Hairs
present
Latex
absent
Uses
The nuts of Castanea are edible; those of Quercus and Fagus are also ocassionally eaten. Cork is made from the bark of Quercus suber. Quercus, Fagus and Castanea provide ornamental trees. The family is exeptionally important as a source of timber for construction, furniture, cabinetry, barrels and other uses.
Chemical characters
· Alkaloids very rarely present. · Proanthocyanidins present (mostly), when present cyanidin or cyanidin and delphinidin. · Flavonols present, quercetin or kaempferol and quercetin or kaempferol, quercetin, and myricetin. · Ellagic acid present (mostly) or absent (4 genera listed). · C3. C3 physiology recorded directly in Quercus.
Distribution maps
(online von http://www.mobot.org/MOBOT/research/APweb/ . Dort zitiert wie unter jedem Diagramm vermerkt):
