Quercus coccinea |
Quercus robusta |
|
---|---|---|
scarlet oak |
robust oak |
|
Habit | Trees, deciduous, to 30 m; lower trunk without stubs of dead branches. | Trees, deciduous, to 13 m. Bark brown or black, roughly furrowed. |
Bark | dark gray to dark brown, irregularly fissured with scaly ridges, inner bark orangish pink. |
|
Twigs | reddish brown, (1-)2-3.5 mm diam., glabrous. |
dark reddish brown, 1.5-2.5 mm diam., densely pubescent or glabrate. |
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 acutely ovate to elliptic, widest at or proximal to middle, 55-120 × 20-50 mm, base cuneate to rounded or subcordate, margins with 6-8 teeth or shallow lobes with rounded sinuses, rarely entire, 1-10 awns, apex acute or attenuate; surfaces abaxially glabrous except for small axillary tufts of tomentum or pubescent along midrib, adaxially glabrous or persistently pubescent near base and along midrib. |
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. |
biennial; cup deeply cup-shaped, 6-9 mm high × 8-12 mm wide, covering 1/4-1/3 nut, outer surface puberulent or glabrate, inner surface uniformly pubescent, scales tightly appressed, acute or attenuate; nut oblong to broadly ellipsoid, 10-22 × 7-10 mm, glabrate, scar diam. 3.5-4.5 mm. |
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. |
buds glossy light brown, acutely ovoid, 4-7 mm, glabrous or pubescent on apical 1/2. |
2n | = 24. |
|
Quercus coccinea |
Quercus robusta |
|
Phenology | Flowering spring. | Flowering spring. |
Habitat | Poor soils, well-drained uplands, dry slopes, and ridges, occasionally on poorly drained sites | Moist wooded canyons in Chisos Mountains |
Elevation | 0-1500 m (0-4900 ft) | 1500 m (4900 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
|
TX |
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.) |
Of conservation concern. After describing this species, C. H. Muller later (1951, 1970) concluded that it represented a hybrid between Quercus emoryi and Q. gravesii. The extreme forms (e.g., the type specimens) of Q. robusta and Q. gravesii are easily differentiated, but these two taxa appear to occupy the ends of a morphologic continuum. Muller's recent view, however, is that Q. robusta deserves species status. The origin of this taxon is still worthy of study. (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. Lobatae |
Sibling taxa | ||
Synonyms | Q. coccinea var. tuberculata | |
Name authority | Münchhausen: Hausvater 5(1): 254. (1770) | C. H. Muller: Torreya 34: 119. (1934) |
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