TREATMENT FROM THE JEPSON MANUAL	previous taxon | next taxon Jepson Interchange (more information)
	©Copyright 1993 by the Regents of the University of California Print edition is available from the University of California Press

	The second edition of The Jepson Manual (2012) is available from the University of California Press
	See also the Jepson eFlora, which parallels the Second Edition

FAGACEAE

OAK FAMILY

John M. Tucker

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 1–few-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 5–6, minute; petals 0; stamens 4–12+
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 1–3 nuts subtended by spiny, bur-like involucre; nut maturing in 1–2 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).

QUERCUS

OAK

Evergreen or deciduous
Leaf: stipules small, generally early deciduous
Staminate inflorescences: catkins, 1–several, slender, on proximal part of twig
Pistillate inflorescence axillary among upper leaves, short-stalked; flower generally 1
Staminate flower: calyx 4–6-lobed, minute; stamens 4–10
Pistillate flower: calyx minute, generally 6-lobed; ovary enclosed by involucre
Fruit: acorn, maturing in 1–2 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

Q. lobata Née

VALLEY OAK, ROBLE

Tree < 35 m, deciduous; trunk bark becoming deeply checkered into squarish sections, light grayish
Leaf 5–12 cm; petiole 5–12 mm; blade obovate, tip obtuse to rounded, margin deeply 6–10-lobed, lobes obtuse, generally coarsely 2–3-toothed at tip, upper surface often ± shiny, dark green, lower surface finely tomentose, dull to pale green
Fruit maturing in 1 year; cup 14–30 mm wide, 10–30 mm deep, hemispheric, scales clearly tubercled; nut 30–50 mm, 12–20 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.