|Jepson Flora Project: Jepson Interchange|
|TREATMENT FROM THE JEPSON MANUAL (1993)||
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Jepson Interchange (more information)
©Copyright 1993 by the Regents of the University of California
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.
Shrub 13 m, evergreen; twigs tomentose, sometimes becoming glabrous
Leaf 1.53 cm; petiole < 5 mm; blade oblong to elliptic, convex above, tip spiny or abruptly pointed, margin rolled under, toothed, teeth spiny or abruptly pointed, upper surface puberulent, dull green, lower surface short-hairy, pale green
Fruit maturing in 1 year; cup 1218 mm wide, 46 mm deep, bowl-shaped, scales tubercled; nut 1525 mm, ovoid to cylindric, tip obtuse or rounded, shell glabrous inside
Elevation: 1501500 m.
Bioregional distribution: North Coast Ranges, n Sierra Nevada Foothills, San Francisco Bay Area, South Coast Ranges, San Gabriel Mountains.
Hybridizes with Q. berberidifolia, Q. garryana.