The families of flowering plants
Alternatively Cupuliferae A. Rich. (Is.str.), Cupulaceae Dulac
Including Nothofagaceae Kuprianova, Quercineae (Quercaceae) Juss.Excluding Corylaceae
Habit and leaf form. Trees and shrubs; leptocaul. Mesophytic. Leaves evergreen, or deciduous; medium-sized; alternate; spiral, or distichous to four-ranked (rarely); herbaceous, or leathery; petiolate; non-sheathing; gland-dotted, or not gland-dotted; simple; epulvinate. Lamina dissected, or entire; when dissected, pinnatifid; pinnately veined; cross-venulate. Leaves stipulate. Stipules caducous. Lamina margins entire, or serrate, or dentate. Vegetative buds scaly. Leaves without a persistent basal meristem. Domatia occurring in the family (from 3 genera); manifested as hair tufts (consistently).
Leaf anatomy. Hydathodes present (occasionally), or absent. Mucilaginous epidermis present, or absent. Stomata mainly confined to one surface (abaxial); anomocytic.
Lamina without secretory cavities. Minor leaf veins without phloem transfer cells (Nothofagus, Quercus).
Stem anatomy. Secretory cavities absent. Cork cambium present; initially superficial. Nodes tri-lacunar. Internal phloem absent. Secondary thickening developing from a conventional cambial ring. The secondary phloem stratified into hard (fibrous) and soft (parenchymatous) zones, or not stratified. Included phloem absent. Xylem with libriform fibres, or without libriform fibres; with vessels. Vessel end-walls scalariform, or scalariform and simple. Vessels without vestured pits. Wood partially storied (VR, Nothofagus), or not storied; parenchyma apotracheal (diffuse or in fine lines).
Reproductive type, pollination. Plants monoecious (nearly always), or dioecious (rarely). Gynoecium of male flowers pistillodial to absent. Pollination anemophilous (usually), or entomophilous (e.g. Castanea).
Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in inflorescences; when solitary, axillary; when aggregated, in catkins (usually, at least the males), or in heads, or in glomerules. The ultimate inflorescence unit cymose. Inflorescences when flowers aggregated, axillary; with male flowers usually in more or less reduced dichasia aggregated into aments or distributed along a branching axis, the females in 17(15)-flowered clusters at the bases of these or in separate few-flowered inflorescences; with involucral bracts. The involucres accrescent (and sometimes cupular, subtending the fruit or sometimes enclosing it). Flowers bracteate; minute. Free hypanthium absent.
Perianth sepaline, or vestigial; (4–)6(–7); free to joined; 1 whorled. Calyx (if the perianth is so interpreted) (4–)6(–7) (in the form of small scales); polysepalous, or gamosepalous; blunt-lobed; regular; in male flowers imbricate.
Androecium (4–)6–12(–40) (in male flowers). Androecial members free of the perianth; all equal; free of one another; 1 whorled (or more when numerous?). Androecium exclusively of fertile stamens. Stamens (4–)6–12(–40); isomerous with the perianth to diplostemonous to polystemonous; oppositisepalous, or alternisepalous and oppositisepalous. Anthers dehiscing via longitudinal slits. Pollen grains aperturate; 3 aperturate, or 4–7 aperturate; colpate, or colporate; 2-celled.
Gynoecium (2–)3 carpelled (usually), or 6(–12) carpelled. The pistil (2–)3 celled (usally), or 6(–12) celled. Gynoecium syncarpous; synovarious; inferior. Ovary (2–)3 locular (usually), or 6(–12) locular (but the septa falling short of the one-locular apex). The odd carpel when G3 anterior. Styles (2–)3 (usually), or 6(–12) (as many as the locules); free; apical. Stigmas dry type; non-papillate; Group II type. Placentation axile, or apical. Ovules 2 per locule; pendulous; non-arillate; anatropous; bitegmic (usually), or unitegmic (Nothofagus); crassinucellate. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; proliferating (sometimes), or not proliferating. Synergids sometimes with filiform apparatus. Endosperm formation nuclear. Embryogeny onagrad.
Fruit non-fleshy; indehiscent (subtended by the accrescent involucre, which sometimes encloses it before opening like a pericarp); a nut (with stony or leathery pericarp), or a samara (rarely); usually 1 seeded (by abortion). Seeds non-endospermic. Seeds with starch. Cotyledons 2. Embryo achlorophyllous (3/8).
Seedling. Germination phanerocotylar (e.g. Fagus), or cryptocotylar (e.g. Castanea).
Physiology, biochemistry. Not cyanogenic. Alkaloids present (very rarely), or absent. Iridoids not detected. Proanthocyanidins present (mostly), or absent; 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). Arbutin absent. Aluminium accumulation demonstrated (perhaps, in Quercus spp.), or not found (mostly). Sugars transported as sucrose, or as oligosaccharides + sucrose, or as sugar alcohols + oligosaccharides + sucrose (but sucrose always predominating, in 29 species from 3 genera). C3. C3 physiology recorded directly in Quercus.
Geography, cytology. Frigid zone, temperate, and sub-tropical. Cosmopolitan, except tropical South America and tropical and South Africa. X = (11-)12(-13).
Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgrens Superorder Rosiflorae; Fagales. Cronquists Subclass Hamamelidae; Fagales. APG 3 core angiosperms; core eudicot; Superorder Rosanae; fabid; Order Fagales.
Species about 900. Genera 9; Fagus, Nothofagus, Lithocarpus, Castanopsis, Colombobalanus, Castanea, Chrysolepis, Quercus, Trigonobalanus.
Economic uses, etc. Important sources of hardwood timber (oak, beech, chestnut), chestnuts (Castanea), and (from Quercus) cork and tannins.
Illustrations. • Technical details: Castanea, Fagus. • Technical details: Quercus. • Castanea sativa (as C. vulgaris): Eng. Bot. 1290, 1868. • Colombobalanus (R.E Halling, photo). • Fagus sylvatica (B. Ent.). • Fagus sylvatica: Eng. Bot. 1291, 1868. • Quercus robur (as Q. pedunculata) and Q. petraea (as Q. sessiliflora): Eng. Bot. 1288 and 1289, 1868.
And many strokes,
though with a little axe,
Hew down and fell the hardest-timbered oak
(3rd Henry the Sixth, ii., 1)
He lay along,
Under an oak whose antique roots peep out
Upon the brook that brawls along this wood
(As You Like It, ii., 1) ;
(An oak . .) Whose boughs were
mossd with age,
And high top bald with dry antiquity
(As You Like It, iv., 3)
I have seen tempests when the scolding winds
Have rived the knotty oaks
(Julius Caesar, i., 3)
All the elves
Creep into acorn-cups, and hide them there
(Midsummer Nights Dream, i., 1)
Sweet chestnuts brown, like soleing leather
(John Clare c.1850, The Winters Come Castanea)
This description is offered for casual browsing only. We strongly advise against extracting comparative information from it. This is much more easily achieved using the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, genera included in each family, and classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG).
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 19th December 2012. http://delta-intkey.com’.