TREATMENT FROM THE JEPSON MANUAL (1993) |
previous taxon |
next taxon
Jepson Interchange (more information) |
|
©Copyright 1993 by the Regents of the University of California
For up-to-date information about California vascular plants, visit the Jepson eFlora. |
AND IS MAINTAINED FOR ARCHIVAL PURPOSES ONLY |
Shrub or tree, monoecious, deciduous or evergreen
Leaves simple, alternate, petioled; margin entire to lobed; stipules small, generally deciduous
Staminate inflorescence: catkin or stiff spike; flowers many
Pistillate inflorescence 1few-flowered, generally above staminate inflorescence; involucre in fruit generally cup-like or lobed and bur-like, bracts many, generally overlapping, flat or cylindric
Staminate flower: sepals generally 56, minute; petals 0; stamens 412+
Pistillate flower: calyx generally 6-lobed, minute; petals 0; ovary inferior, style branches generally 3
Fruit: acorn (nut subtended by scaly, cup-like involucre) or 13 nuts subtended by spiny, bur-like involucre; nut maturing in 12 years
Seed generally 1
Genera in family: 7 genera, ± 900 species: generally n hemisphere. Wood of Quercus critical for pre-20th century ship-building, charcoal for metallurgy; some now supply wood (Fagus, Quercus ), cork (Q. suber ), food (Castanea , chestnut).
Evergreen or deciduous
Leaf: stipules small, generally early deciduous
Staminate inflorescences: catkins, 1several, slender, on proximal part of twig
Pistillate inflorescence axillary among upper leaves, short-stalked; flower generally 1
Staminate flower: calyx 46-lobed, minute; stamens 410
Pistillate flower: calyx minute, generally 6-lobed; ovary enclosed by involucre
Fruit: acorn, maturing in 12 years; nut enclosed by cup-like involucre with thin or tubercled scales
Chromosomes: 2n=24 for all reports
Species in genus: ± 600 species: n hemisphere, to n South America, India
Etymology: (Latin: ancient name for oak)
Many more hybrids have been named but are not included here. Reproduction of many species declining.
Native |
Tree 820 m or shrub 15 m, deciduous; trunk bark thin, becoming widely ridged, scaly, grayish; twigs short-hairy, becoming glabrous, reddish brown
Leaf 515 cm; petiole 525 mm; blade elliptic to obovate, tip obtuse to rounded, margin deeply 57-lobed, lobes entire or 2-toothed, upper surface shiny, dark green, lower surface short-hairy, dull, light green
Fruit maturing in 1 year; cup 1225 mm wide, 49 mm deep, cup- to bowl-shaped, scales ± flat to slightly tubercled; nut 2030 mm, ± ovoid to subspheric, tip rounded, shell glabrous inside
Ecology: Slopes, woodland, mixed-evergreen or conifer forest
Elevation: 3001800 m.
Bioregional distribution: Northwestern California, Cascade Range Foothills, Sierra Nevada Foothills, Tehachapi Mountain Area, San Francisco Bay Area, ne Western Transverse Ranges (Liebre Mtn)
Distribution outside California: to British Columbia