|Jepson Flora Project: Jepson Interchange|
|TREATMENT FROM THE JEPSON MANUAL (1993)||
previous taxon |
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 515 m, deciduous; trunk bark scaly, grayish; twigs tomentose
Leaf 47 cm; petiole 310 mm; blade oblong to obovate, tip obtuse to rounded, margin 26(8)-lobed, lobes generally pointed, upper surface glabrous to sparsely hairy, green, ± shiny, lower surface densely appressed-stellate-hairy, ± pale green
Fruit maturing in 1 year; cup 1020 mm wide, 610 mm deep, hemispheric, scales clearly tubercled, canescent; nut 2035 mm, conic-oblong to ovoid, tip acute, shell glabrous inside
Ecology: Slopes, canyons, woodland
Elevation: < 600 m.
Bioregional distribution: Channel Islands (except San Clemente Island).Considered by Greene as sp. but derived from hybrids between Q. berberidifolia and Q. lobata ; perhaps other species involved; needs further study
Horticultural information: DRN, SUN: 5, 7, 8, 9, 10, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24.