Quercus ellipsoidalis |
Quercus bicolor |
|
---|---|---|
Hill's oak, Jack oak, northern pin oak |
chêne bicolore, swamp white oak |
|
Habit | Trees, deciduous, to 20 m; lower trunk often with stubs of dead branches. | Trees, deciduous, to 30 m. Bark dark gray, scaly or flat-ridged. |
Bark | dark gray-brown, shallowly fissured, inner bark orangish. |
|
Twigs | dark reddish brown, (1-)1.5-3 mm diam., glabrous. |
light brown or tan, 2-3(-4) mm diam., glabrous. |
Buds | light or dark brown, globose to ovoid, 2-3 mm, glabrous. |
|
Leaves | blade elliptic, 70-130 × 50-100 mm, base obtuse to truncate, margins with 5-7 deep lobes and 15-55 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 to narrowly elliptic or narrowly obovate, (79-)120-180(-215) × (40-)70-110(-160) mm, base narrowly cuneate to acute, margins regularly toothed, or entire with teeth in distal 1/2 only, or moderately to deeply lobed, or sometimes lobed proximally and toothed distally, secondary veins arched, divergent, (3-)5-7 on each side, apex broadly rounded or ovate; surfaces abaxially light green or whitish, with minute, flat, appressed-stellate hairs and erect, 1-4-rayed hairs, velvety to touch, adaxially dark green, glossy, glabrous. |
Acorns | biennial; cup narrowly turbinate to deeply cup-shaped, 6-11 mm high × 10-19 mm wide, covering 1/3-1/2 nut, outer surface reddish brown, puberulent, inner surface light brown, glabrous, rarely with ring of pubescence around scar, scales with straight or slightly concave margins, tips tightly appressed, obtuse or acute; nut ellipsoid to ovoid, rarely subglobose, 10-20 × 9-15 mm, occasionally striate, glabrous, occasionally with 1 or more faint rings of fine pits at apex, scar diam. 4-8 mm. |
1-3(-5) mm, on thin axillary peduncle (20-)40-70 mm; cup hemispheric or turbinate, 10-15 mm deep × 15-25 mm wide, enclosing 1/2-3/4 nut, scales closely appressed, finely grayish tomentose, those near rim of cup often with short, stout, irregularly recurved and sometimes branched, spinose awns emerging from tubercle; nut light brown, ovoid-ellipsoid or oblong, (12-)15-21(-25) × 9-18 mm, glabrous. |
Cotyledons | distinct. |
|
Terminal | buds dark reddish brown, ovoid, 3-5 mm, often conspicuously 5-angled in cross section, usually silvery- or tawny-pubescent toward apex. |
|
2n | = 24. |
|
Quercus ellipsoidalis |
Quercus bicolor |
|
Phenology | Flowering spring. | Flowering in spring. |
Habitat | Dry sandy sites, rarely on moderately mesic slopes or uplands | Low swamp forests, moist slopes, poorly drained uplands |
Elevation | 150-500 m (500-1600 ft) | 0-1000 m (0-3300 ft) |
Distribution |
IA; IL; IN; MI; MN; OH; WI; ON
|
AL; CT; DE; IA; IL; IN; KY; MA; MD; ME; MI; MN; MO; NC; NH; NJ; NY; OH; PA; RI; TN; VA; VT; WI; WV; ON; QC
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Discussion | In many treatments (e.g., E. G. Voss 1972+, vol. 2), Quercus ellipsoidalis is included in Q. coccinea. Variation in fruit morphology has led to recognition of several formae (W. Trelease 1919; see also R. J. Jensen 1986) and one variety (Q. ellipsoidalis var. kaposianensis, based on specimens from St. Paul, Minnesota, in which the cup tightly encloses the nut for two-thirds its length at maturity). Quercus ellipsoidalis reportedly hybridizes with Q. rubra and Q. velutina. The Menominee used Quercus ellipsoidalis medicinally to treat suppressed menses caused by cold (D. E. Moerman 1986). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Putative hybrids between Quercus bicolor and Q. macrocarpa are common in areas of contact. The hybrids tend to have more deeply lobed leaves and varying degrees of development of awns as a fringe along the margin of the acorn cup. Such characteristics occur sporadically throughout many populations of Q. bicolor; in some cases they may occur because of subtle introgression. The Iroquois used Quercus bicolor in the treatment of cholera, broken bones, consumption, and as a witchcraft medicine (D. E. Moerman 1986). (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. ellipsoidalis var. kaposianensis | Q. bicolor var. angustifolia, Q. bicolor var. cuneiformis, Q. bicolor var. platanoides, Q. platanoides |
Name authority | E. J. Hill: Bot. Gaz. 27: 204, plates 2, 3. (1899) | Willdenow: in G. H. E. Muhlenberg, Ges. Naturf. Freunde Berlin Neue Schriften 3: 396. (1801) |
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