Quercus coccinea |
Quercus douglasii |
|
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scarlet oak |
blue oak |
|
Habit | Trees, deciduous, to 30 m; lower trunk without stubs of dead branches. | Trees, deciduous, with single trunks, sometimes with few to several trunks. |
Bark | dark gray to dark brown, irregularly fissured with scaly ridges, inner bark orangish pink. |
gray, scaly. |
Twigs | reddish brown, (1-)2-3.5 mm diam., glabrous. |
reddish or yellowish, ca. 2 mm, densely or sparsely puberulent, occasionally glabrate with age. |
Buds | reddish brown, rarely yellowish, broadly ovoid to rarely subglobose, (2-)3-5 mm; scales glabrous except for ciliate margins, sometimes sparsely or densely pubescent. |
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Leaves | blade elliptic to ovate or obovate, 70-160 × 80-130 mm, base obtuse to truncate, margins with 5-9 deep lobes and 18-50 awns, lobes distally expanded, sinuses usually extending more than 1/2 distance to midrib, apex acute; surfaces abaxially glabrous except for minute axillary tufts of tomentum, adaxially glossy light green, glabrous, secondary veins raised on both surfaces. |
blade obovate or elliptic, oblong or oblanceolate, (20-)40-60(-80) × (15-)20-30(-40) mm, base rounded-attenuate or rounded, rarely cuneate, margins shallowly lobed or irregularly toothed, sometimes entire, lobes mucronate or rounded, secondary veins 6-10 on each side, apex rounded, rarely moderately acute; surfaces abaxially light green or blue-green, waxy, with scattered to crowded, semi-erect, (2-)4-6(-8)-rayed stellate hairs usually 0.2-0.6 mm diam. or larger, adaxially blue-green, glaucous or grayish, vestiture similar to abaxial surface. |
Acorns | biennial; cup turbinate to hemispheric, 7-13 mm high × 16.5-31.5 mm wide, covering 1/3-1/2 nut, outer surface light to dark reddish brown, glossy, glabrous to puberulent, inner surface light brown, glabrous, occasionally with ring of pubescence around scar, scales often tuberculate, base broad, glossy, margins strongly concave with tips tightly appressed, acute to attenuate; nut oblong to subglobose, 12-22 × 10-21 mm, glabrous, with 1 or more rings of fine pits at apex, scar diam. 6.5-13.5 mm. |
subsessile, solitary; cup hemispheric or cup-shaped, rarely deeper, 5-10 mm deep × 10-15 mm wide, enclosing only base of nut, scales thin and not tuberculate to strongly and irregularly tuberculate, particularly toward base of cup; nut thin-walled, fusiform or subcylindric, 20-30 × 10-16 mm. |
Cotyledons | distinct. |
|
Terminal | buds dark reddish brown, conic to ovoid, 4-7 mm, noticeably 5-angled in cross section, usually silvery- or tawny-pubescent distal to middle. |
|
2n | = 24. |
= 24. |
Quercus coccinea |
Quercus douglasii |
|
Phenology | Flowering spring. | Flowering late winter–spring. |
Habitat | Poor soils, well-drained uplands, dry slopes, and ridges, occasionally on poorly drained sites | Oak woodlands, margins of chaparral and grasslands |
Elevation | 0-1500 m (0-4900 ft) | 0-1200 m (0-3900 ft) |
Distribution |
AL; AR; CT; DC; DE; GA; IL; IN; KY; MA; MD; ME; MI; MO; NC; NH; NJ; NY; OH; PA; RI; SC; TN; VA; VT; WI; WV
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CA
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Discussion | Trees having acorns with broad, distinctly warty cups are sometimes classified as Quercus coccinea var. tuberculata Sargent. Quercus coccinea reportedly hybridizes with Q. imbricaria, Q. ilicifolia (= Q. ×robbinsii Trelease), Q. laevis, and Q. palustris (E. J. Palmer 1948) and with Q. phellos, Q. rubra, and Q. velutina (= Q. ×fontana Laughlin). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Populations of Quercus douglasii in coastal southern California and on the Channel Islands consist of small stands or solitary individuals often associated with Q. lobata and scrub oaks. Some doubt exists as to whether some or all of those populations are natural stands or are historical introductions near Native American settlements. Along the canyons of Santa Barbara County, putative hybrids between Q. douglasii and Q. dumosa are referred to Q. ×kinselae (C. H. Muller) Nixon. In the interior Coast Ranges of California are found numerous populations that are intermediate in form between Q. douglasii and Q. john-tuckeri (= Q. turbinella var. californica). This appears to be an area of secondary contact, and the two species remain distinct in nearby populations. Because of the widespread nature of the intermediates, following Tucker's extensive studies they can be conveniently referred to as the nothospecies Q. ×alvordiana Eastwood. The plants tend to be shrubs to small trees, with somewhat more spinose leaves than Q. douglasii and fruit similar to those of the latter species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 3. | FNA vol. 3. |
Parent taxa | Fagaceae > Quercus > sect. Lobatae | Fagaceae > Quercus > sect. Quercus |
Sibling taxa | ||
Synonyms | Q. coccinea var. tuberculata | Q. douglasii var. ransomii, Q. ransomii |
Name authority | Münchhausen: Hausvater 5(1): 254. (1770) | Hooker & Arnott: Bot. Beechey Voy. 9: 391. (1840) |
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