|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.
Tree < 35 m, deciduous; trunk bark becoming deeply checkered into squarish sections, light grayish
Leaf 512 cm; petiole 512 mm; blade obovate, tip obtuse to rounded, margin deeply 610-lobed, lobes obtuse, generally coarsely 23-toothed at tip, upper surface often ± shiny, dark green, lower surface finely tomentose, dull to pale green
Fruit maturing in 1 year; cup 1430 mm wide, 1030 mm deep, hemispheric, scales clearly tubercled; nut 3050 mm, 1220 mm wide, generally long-conic, tapered to pointed tip, shell glabrous inside
Ecology: UNCOMMON. Slopes, valleys, savannah
Elevation: < 1700 m.
Bioregional distribution: North Coast Ranges, Cascade Range Foothills, Sierra Nevada Foothills, Tehachapi Mountain Area, Great Central Valley, San Francisco Bay Area, South Coast Ranges, nw South Coast, Channel Islands (Santa Cruz, Santa Catalina islands), Western Transverse Ranges, w San Gabriel Mountains.
Hybridizes with Q. berberidifolia, Q. cornelius-mulleri, Q. douglasii, Q. engelmannii, Q. garryana, Q. john-tuckeri.
Horticultural information: SUN: 4, 5, 6, 14, 15, 16, 17 &IRR, DRN: 1, 2, 3, 7, 8, 9, 18, 19, 20, 21, 22, 23, 24.