The Families of Flowering Plants

L. Watson and M. J. Dallwitz


Fagaceae Dum.

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 recorded (from 3 genera); represented by 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. 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 terminal 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 1–7(–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. Dahlgren’s Superorder Rosiflorae; Fagales. Cronquist’s Subclass Hamamelidae; Fagales. APG (1998) Eudicot; core Eudicot; Rosid; Eurosid I; 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, Quercus). • Colombobalanus.

Quotations

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 moss’d 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 for fear,
Creep into acorn-cups, and hide them there
(‘Midsummer Night’s Dream’, i., 1)

Sweet chestnuts brown, like soleing leather turn,
(John Clare c.1850, ‘The Winter’s Come’ — Castanea)


Cite this publication as: ‘L. Watson and M. J. Dallwitz (1992 onwards). The Families of Flowering Plants: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 14th December 2000. http://biodiversity.uno.edu/delta/’. Dallwitz (1980), Dallwitz, Paine and Zurcher (1993, 1995, 2000), and Watson and Dallwitz (1991) should also be cited (see References).

Index