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Quercus lobata

Higher Taxonomy
Family: FagaceaeView DescriptionDichotomous Key

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
Genus: QuercusView DescriptionDichotomous Key

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.
Species In Genus: +- 600 species: northern hemisphere, to northern South America, India. 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

Quercus lobata Née
Habit: Tree < 35 m, deciduous; trunk bark thin, scaly, +- light gray. Leaf: 5--12 cm; petiole 5--12 mm; blade obovate, adaxially often +- shiny, dark green, abaxially fine-tomentose, dull to pale green, base wedge-shaped, rounded-gradually tapered, or truncate (subcordate), tip obtuse to rounded, margin lobes 6--10 per leaf, deep (sinuses generally > 1/2 distance lobe tip to midrib), obtuse, generally coarsely 2--3-toothed at tip. Fruit: cup 14--30 mm wide, 10--30 mm deep, hemispheric, scales tubercled; nut 30--50 mm, 12--20 mm wide, generally long-conic, distally acute to +- obtuse, shell glabrous inside; mature in year 1.
Ecology: Slopes, valleys, savanna; Elevation: < 1830 m. Bioregional Distribution: KR, NCoR, CaRF, SNF, s SNH, Teh, GV, SnFrB, SCoR, nw SCo, ChI (Santa Cruz, Santa Catalina islands), WTR, w SnGb. Flowering Time: Mar--Apr Note: Hybridizes with Quercus berberidifolia, Quercus cornelius-mulleri, Quercus douglasii, Quercus engelmannii, Quercus garryana, Quercus john-tuckeri, Quercus pacifica (Quercus ×macdonaldii), Quercus robur.
Synonyms: Quercus lobata f. insperata Jeps.; Quercus lobata f. rarita Jeps.; Quercus lobata var. lobata; Quercus lobata var. turbinata Jeps.; Quercus lobata var. walteri Jeps.
eFlora Treatment Author: Thomas J. Rosatti & John M. Tucker
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botanical illustration including Quercus lobata


Citation for this treatment: Thomas J. Rosatti & John M. Tucker 2016. Quercus lobata, Revision 2, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on May 31, 2016.

Citation for the whole project: Jepson Flora Project (eds.) 2016. Jepson eFlora,, accessed on May 31, 2016.

Quercus lobata
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© 2008 Keir Morse
Quercus lobata
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© 2013 Neal Kramer
Quercus lobata
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© 2009 Neal Kramer
Quercus lobata
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© 2012 Neal Kramer
Quercus lobata
click for enlargement
© 2008 Keir Morse
Quercus lobata
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© 2014 Neal Kramer

More photos of Quercus lobata in CalPhotos

Geographic subdivisions for Quercus lobata:
KR, NCoR, CaRF, SNF, s SNH, Teh, GV, SnFrB, SCoR, nw SCo, ChI (Santa Cruz, Santa Catalina islands), WTR, w SnGb.
Markers link to CCH specimen records. Yellow markers indicate records that may provide evidence for eFlora range revision or may have georeferencing or identification issues. Purple markers indicate specimens collected from a garden, greenhouse, or other non-wild location.
map of distribution 1
(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).

View elevation by latitude chart
Data provided by the participants of the Consortium of California Herbaria.
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CCH collections by month

Duplicates counted once; synonyms included.
Species do not include records of infraspecific taxa.
Blue line denotes eFlora flowering time.