Common Name: OAK FAMILY Habit: Shrub, tree, evergreen or not; monoecious. Leaf: simple, alternate, petioled; margin entire to lobed; stipules small, generally deciduous. Staminate Inflorescence: catkin or stiff spike, many-flowered. Pistillate Inflorescence: 1--few-flowered, generally above staminate inflorescence; involucre bracts many, generally overlapping, flat or cylindric. Staminate Flower: calyx generally 4--6-lobed, minute; petals 0; stamens 4--12+. Pistillate Flower: calyx generally 6-lobed, minute; petals 0; ovary inferior, style branches generally 3. Fruit: 1 nut subtended, partly enclosed by scaly, cup-like involucre or 1--3 nuts subtended, enclosed by spiny, bur-like involucre; mature years 1--2. Seed: generally 1. Genera In Family: 7 genera, +- 900 species: generally northern hemisphere. Note: Wood of Quercus critical for pre-20th century ship-building, charcoal for metallurgy; some now supply wood (Fagus, Quercus), cork (Quercus suber), food (Castanea, chestnut). Lithocarpus densiflorus moved to Notholithocarpus. eFlora Treatment Author: John M. Tucker, except as noted Scientific Editor: Thomas J. Rosatti, Bruce G. Baldwin.
Common Name: OAK Habit: Evergreen or not. Leaf: stipules small, generally early-deciduous. Staminate Inflorescence: catkins, 1--several, pendent, slender, proximal on twig. Pistillate Inflorescence: in distal leaf axils, short-stalked; flower generally 1. Staminate Flower: stamens 4--10. Pistillate Flower: calyx minute, generally 6-lobed; ovary enclosed by involucre. Fruit: nut 1, partly enclosed by cup-like involucre (cup) with appressed scales (nut and cup = acorn), remnants of perianth and style persistent as small point at tip; scales tubercled to not; mature in years 1 (on younger stems) or 2 (on older stems). Chromosomes: 2n=24. Etymology: (Latin: ancient name for oak) Note: Many named hybrids; those (3) treated here form widespread populations; most others occur as single individuals, and some but not all of these are mentioned here, under the first parent treated (alphabetically). Reproduction of many species declining due to habitat degradation or loss as well as disease. Quercus robur added, as waif. eFlora Treatment Author: Thomas J. Rosatti & John M. Tucker Reference: Manos et al. 1999 Molec Phylogen Evol 12:333--349 Unabridged Reference: Cottam, W. P., J. M. Tucker, & F. S. Santamour. 1982. Oak hybridization at the University of Utah. State Arboretum of Utah Publication No. 1. Salt Lake City; Hardin, J. W. 1975. Hybridization and introgression in Quercus alba. Journal of the Arnold Arboretum 56: 336--363; Manos, P. S., Doyle, J. J., & Nixon, K. C. 1999. Phylogeny, biogeography, and processes of molecular differentiation of Quercus subgenus Quercus (Fagaceae). Molec Phylogen Evol 12: 333--349.
Quercus dumosa Nutt.
NATIVE Habit: Shrub 1--4 m, generally evergreen; twigs slender, 1--1.5 mm diam, sparsely short-hairy, dark red-brown, glabrous in age. Leaf: 1--2.5 cm; petiole < 5 mm; blade oblong, elliptic, or +- round, adaxially +- convex or not, +- shiny, green, abaxially fine-tomentose, in age glabrous, dull, pale green, tip obtuse to abruptly pointed, margin +- wavy or not, +- spine-toothed. Fruit: cup 8--15 mm wide, 5--8 mm deep, generally bowl-shaped, scales +- tubercled; nut 10--20 mm, +- slender, generally ovoid, distally acute to obtuse, shell glabrous inside; mature in year 1. Ecology: Generally sandy soils near coast, sandstone, chaparral, coastal-sage scrub; Elevation: < 200 m. Bioregional Distribution: SCo, PR; Distribution Outside California: Baja California. Flowering Time: Mar--May Note: Hybridizes with Quercus berberidifolia, Quercus douglasii, Quercus engelmannii, Quercus garryana (Quercus ×eplingii C.H. Mull.), Quercus lobata (Quercus ×kinseliae (C.H. Mull.) Nixon & C.H. Mull., Quercus dumosa var. kinseliae C.H. Mull.). Jepson eFlora Author: Thomas J. Rosatti & John M. Tucker Reference: Manos et al. 1999 Molec Phylogen Evol 12:333--349 Index of California Plant Names (ICPN; linked via the Jepson Online Interchange) Listed on CNPS Rare Plant Inventory Previous taxon: Quercus douglasii Next taxon: Quercus durata
Citation for this treatment: Thomas J. Rosatti & John M. Tucker 2014, Quercus dumosa, in Jepson Flora Project (eds.) Jepson eFlora, Revision 2, https://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=40582, accessed on April 17, 2024.
Citation for the whole project: Jepson Flora Project (eds.) 2024, Jepson eFlora, https://ucjeps.berkeley.edu/eflora/, accessed on April 17, 2024.
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(Note: any qualifiers in the taxon distribution description, such as 'northern', 'southern', 'adjacent' etc., are not reflected in the map above, and in some cases indication of a taxon in a subdivision is based on a single collection or author-verified occurence).
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