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Hill's oak, Jack oak, northern pin oak

Arkansas oak

Habit Trees, deciduous, to 20 m; lower trunk often with stubs of dead branches. Trees, deciduous, to 15 m. Bark black with long rough ridges separated by deep furrows.
Bark

dark gray-brown, shallowly fissured, inner bark orangish.

Twigs

dark reddish brown, (1-)1.5-3 mm diam., glabrous.

1.5-3 mm diam., gray-pubescent, rarely glabrate.

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 rhombic to obovate or obtrullate, 50-150 × 35-100 mm, base acute to cordate, margins entire or with 2-3 shallow lobes and up to 10 awns, apex broadly obtuse to rounded;

surfaces abaxially uniformly pubescent to glabrous except for conspicuous axillary tufts of tomentum, veins prominent, adaxially planar or somewhat rugose with a few persistent hairs near base.

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 thin, shallow goblet- to almost saucer-shaped, 5-9 mm high × 10-16 mm wide, covering 1/4-1/2 nut, outer surface puberulent, inner surface sparsely to uniformly pubescent, scale tips appressed, acute;

nut broadly ellipsoid to subglobose, 10-15 × 9-15 mm, puberulent, scar diam. 5-10 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 red-brown, ovoid, 2-5 mm, glabrous or with scales somewhat ciliate on margins, especially at apex.

Quercus ellipsoidalis

Quercus arkansana

Phenology Flowering spring. Flowering spring.
Habitat Dry sandy sites, rarely on moderately mesic slopes or uplands An understory tree of well-drained, sandy soils, on ravine heads (pocosins, steepheads)
Elevation 150-500 m (500-1600 ft) 50-150 m (200-500 ft)
Distribution
from FNA
IA; IL; IN; MI; MN; OH; WI; ON
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; FL; GA; LA; TX
[WildflowerSearch map]
[BONAP county map]
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.)

Quercus arkansana reportedly hybridizes with Q. incana (= Q. ×venulosa Ashe) and Q. nigra (D. M. Hunt 1986; W. H. Duncan and M. B. Duncan 1988). While agreeing that an isotype of the former clearly indicated a relationship to Q. arkansana, E. J. Palmer (1948) questioned the identity of the second parent and noted that venulosa is a homonym of a fossil species. In addition, D. M. Hunt (1989) cited evidence of hybridization with Q. hemisphaerica, Q. laevis, Q. marilandica, Q. myrtifolia, and either Q. falcata or Q. velutina.

(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
Q. acerifolia, Q. agrifolia, Q. ajoensis, Q. alba, Q. arizonica, Q. arkansana, Q. austrina, Q. berberidifolia, Q. bicolor, Q. boyntonii, Q. buckleyi, Q. carmenensis, Q. chapmanii, Q. chihuahuensis, Q. chrysolepis, Q. coccinea, Q. cornelius-mulleri, Q. depressipes, Q. douglasii, Q. dumosa, Q. durata, Q. emoryi, Q. engelmannii, Q. falcata, Q. fusiformis, Q. gambelii, Q. garryana, Q. geminata, Q. georgiana, Q. graciliformis, Q. gravesii, Q. grisea, Q. havardii, Q. hemisphaerica, Q. hinckleyi, Q. hypoleucoides, Q. ilicifolia, Q. imbricaria, Q. incana, Q. inopina, Q. intricata, Q. john-tuckeri, Q. kelloggii, Q. laceyi, Q. laevis, Q. laurifolia, Q. lobata, Q. lyrata, Q. macrocarpa, Q. margarettae, Q. marilandica, Q. michauxii, Q. minima, Q. mohriana, Q. montana, Q. muehlenbergii, Q. myrtifolia, Q. nigra, Q. oblongifolia, Q. oglethorpensis, Q. pacifica, Q. pagoda, Q. palmeri, Q. palustris, Q. phellos, Q. polymorpha, Q. prinoides, Q. pumila, Q. pungens, Q. robur, Q. robusta, Q. rubra, Q. rugosa, Q. sadleriana, Q. shumardii, Q. similis, Q. sinuata, Q. stellata, Q. tardifolia, Q. texana, Q. tomentella, Q. toumeyi, Q. turbinella, Q. vacciniifolia, Q. vaseyana, Q. velutina, Q. viminea, Q. virginiana, Q. wislizenii
Q. acerifolia, Q. agrifolia, Q. ajoensis, Q. alba, Q. arizonica, Q. austrina, Q. berberidifolia, Q. bicolor, Q. boyntonii, Q. buckleyi, Q. carmenensis, Q. chapmanii, Q. chihuahuensis, Q. chrysolepis, Q. coccinea, Q. cornelius-mulleri, Q. depressipes, Q. douglasii, Q. dumosa, Q. durata, Q. ellipsoidalis, Q. emoryi, Q. engelmannii, Q. falcata, Q. fusiformis, Q. gambelii, Q. garryana, Q. geminata, Q. georgiana, Q. graciliformis, Q. gravesii, Q. grisea, Q. havardii, Q. hemisphaerica, Q. hinckleyi, Q. hypoleucoides, Q. ilicifolia, Q. imbricaria, Q. incana, Q. inopina, Q. intricata, Q. john-tuckeri, Q. kelloggii, Q. laceyi, Q. laevis, Q. laurifolia, Q. lobata, Q. lyrata, Q. macrocarpa, Q. margarettae, Q. marilandica, Q. michauxii, Q. minima, Q. mohriana, Q. montana, Q. muehlenbergii, Q. myrtifolia, Q. nigra, Q. oblongifolia, Q. oglethorpensis, Q. pacifica, Q. pagoda, Q. palmeri, Q. palustris, Q. phellos, Q. polymorpha, Q. prinoides, Q. pumila, Q. pungens, Q. robur, Q. robusta, Q. rubra, Q. rugosa, Q. sadleriana, Q. shumardii, Q. similis, Q. sinuata, Q. stellata, Q. tardifolia, Q. texana, Q. tomentella, Q. toumeyi, Q. turbinella, Q. vacciniifolia, Q. vaseyana, Q. velutina, Q. viminea, Q. virginiana, Q. wislizenii
Synonyms Q. ellipsoidalis var. kaposianensis Q. caput-rivuli
Name authority E. J. Hill: Bot. Gaz. 27: 204, plates 2, 3. (1899) Sargent: Trees & Shrubs 2: 121. (1911)
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