Quercus ellipsoidalis |
Quercus acerifolia |
|
---|---|---|
Hill's oak, Jack oak, northern pin oak |
maple-leaf oak |
|
Habit | Trees, deciduous, to 20 m; lower trunk often with stubs of dead branches. | Trees or shrubs, deciduous, to 15 m. Bark dark gray to almost black, sometimes becoming rough and furrowed. |
Bark | dark gray-brown, shallowly fissured, inner bark orangish. |
|
Twigs | dark reddish brown, (1-)1.5-3 mm diam., glabrous. |
grayish brown to reddish brown, 1.5-3(-3.5) mm diam., glabrous or sparsely pubescent. |
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 oblate to broadly elliptic, 70-140 × (60-)100-150(-180) mm, base cordate-truncate to obtuse, margins with 5-7(-9) lobes and 11-48 awns, lobes ovate-oblong or markedly distally expanded, the middle or apical pairs often overlapping, apex acute; surfaces abaxially glabrous or with prominent axillary tufts of tomentum, occasionally with scattered pubescence, adaxially glabrous, secondary veins raised on both surfaces. |
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. |
biennial; cup saucer- to cup-shaped, 4-7 mm high × 10-20 mm wide, covering 1/4-1/3 nut, outer surface glabrous or puberulent, inner surface light brown to red-brown, glabrous or with ring of pubescence around scar, scales often with pale margins, tips tightly appressed, obtuse or acute; nut ovoid to oblong, 10.5-20 × 9-15 mm, glabrous or pubescent, scar diam. 5-9 mm. |
Terminal | buds dark reddish brown, ovoid, 3-5 mm, often conspicuously 5-angled in cross section, usually silvery- or tawny-pubescent toward apex. |
buds gray to grayish brown, ovoid or broadly ellipsoid, 3.5-5.5 mm, glabrous. |
Quercus ellipsoidalis |
Quercus acerifolia |
|
Phenology | Flowering spring. | Flowering spring. |
Habitat | Dry sandy sites, rarely on moderately mesic slopes or uplands | Dry glades, slopes, and ridge tops |
Elevation | 150-500 m (500-1600 ft) | 500-800 m (1600-2600 ft) |
Distribution |
IA; IL; IN; MI; MN; OH; WI; ON
|
AR |
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.) |
Of conservation concern. Quercus acerifolia is known only from four localities in Arkansas: Magazine Mountain, Logan County; Porter Mountain, Polk County; Pryor Mountain, Montgomery County; and Sugarloaf Mountain, Sebastian County (N. Stoynoff and W. J. Hess 1990; G. P. Johnson 1992, 1994). Some specimens suggest hybridization with Q. marilandica and/or Q. velutina, but no hybrids have been reported. (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. ellipsoidalis var. kaposianensis | Q. shumardii var. acerifolia |
Name authority | E. J. Hill: Bot. Gaz. 27: 204, plates 2, 3. (1899) | (E. J. Palmer) Stoynoff & W. J. Hess ex R. J. Jensen: Fl. N. Amer. 3: 465. (1997) |
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