|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 26 m, evergreen; twigs spreading, rigid
Leaf 13 cm, very stiff; petiole 25 mm; blade elliptic to round-ovate, tip generally spiny, margin wavy and spine-toothed, upper surface glabrous to sparsely puberulent, ± shiny, olive-green, lower surface densely glandular-puberulent when young, pale gray-green
Fruit maturing in 2 years; cup 1025 mm wide, 612 mm deep, generally bowl-shaped, rim ± spreading, scales flat, densely hairy; nut 2030 mm, ± ovoid, tip generally obtuse, shell densely woolly inside
Ecology: Uncommon. Rocky slopes, flats
Elevation: 7001300 m.
Bioregional distribution: e Inner North Coast Ranges (Colusa Co.), nw San Joaquin Valley (Alameda, Contra Costa cos.), San Francisco Bay Area (Alameda Co.), South Coast Ranges (San Luis Obispo, Santa Barbara cos.), San Gabriel Mountains (n slope), e Peninsular Ranges, Desert Mountains (Little San Bernardino Mtns)
Distribution outside California: Arizona, Baja California
Flowering time: AprMay
Synonyms: Q. dunnii Kellogg
Hybridizes with Q. chrysolepis.
Horticultural information: DRN, SUN: 7, 8, 9, 10, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 &IRR: 11; STBL.