Celtis occidentalis |
Ulmaceae |
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bois inconnu, common hackberry, hackberry, micocoulier occidental, western hackberry |
elm family |
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Habit | Trees or shrubs, size varying greatly in response to habitat; crowns rounded. | Trees or shrubs, deciduous (sometimes tardily deciduous in Ulmus). | ||||||||||||
Bark | gray, deeply furrowed, warty with age. |
smooth to deeply fissured or scaly and flaky; sap watery. |
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Branches | without thorns, spreading, young branches mostly pubescent. |
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Leaves | blade lance-ovate to broadly ovate or deltate, 5-12 × 3-6(-9) cm (on fertile branches), leathery, base oblique or obliquely somewhat acuminate, margins conspicuously serrate to well below middle, teeth 10-40, apex acuminate; surfaces scabrous. |
blade: base often oblique, margins entire or serrate, crenate, or toothed; venation pinnate to palmate-pinnate. |
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Inflorescences | dense pendulous clusters. |
axillary, cymes, racemes, fascicles, or flowers solitary, arising from branchlets of previous season (e.g., Ulmus) or of current season (e.g., Celtis). |
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Flowers | bisexual or unisexual, staminate and pistillate on same [different] plants; sepals persistent, (1-)5(-9), connate [distinct], imbricate or valvate; petals absent; stamens usually as many as calyx lobes, hypogynous, opposite calyx lobes, erect in bud; filaments free or arising from calyx tube, distinct, curved or sigmoid in bud; anthers 2-locular, dehiscence longitudinal; pistils 1, 2(-3)-carpellate; ovary 1(-2)-locular; ovules 1 per locule, pendulous from apex of locule, anatropous or amphitropous; styles (1-)2, distinct, receptive stigmatic area decurrent on distal inner margin of style branch. |
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Fruits | fleshy drupes, samaras, or nutlike. |
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Drupes | dark orange to purple- or blue-black when ripe, orbicular, to 7-11(-20) mm diam., commonly with thick beak; pedicel to 15 mm. |
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Seeds | 1; arils absent; endosperm absent to scanty, consisting of 1 layer of thick-walled cells; embryo straight or curved. |
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Wood | light yellow, weak. |
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Stones | cream colored, 7-9 × 5-8 mm, reticulate. |
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2n | = 20, 30, and 40. |
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Celtis occidentalis |
Ulmaceae |
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Phenology | Flowering late winter–spring (Mar–May). | |||||||||||||
Habitat | In rich moist soil along streams, on flood plains, on rock, on wooded hillsides, and in woodlands | |||||||||||||
Elevation | 0-1800 m (0-5900 ft) | |||||||||||||
Distribution |
AL; AR; CO; CT; DC; DE; GA; IA; IL; IN; KS; KY; MA; MD; ME; MI; MN; MO; MS; NC; ND; NE; NH; NJ; NY; OH; OK; PA; RI; SC; SD; TN; TX; VA; VT; WI; WV; WY; MB; ON; QC
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Tropical and north temperate regions |
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Discussion | Celtis occidentalis is valued as an ornamental street tree because of its tolerance to drought. Native Americans used decoctions prepared from the bark of Celtis occidentalis medicinally as an aid in menses and to treat sore throat (D. E. Moerman 1986). This is a highly variable species. Segregates named as varieties follow an east-west geographic gradient and are based primarily on leaf size, shape, and pubescence. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Genera ca. 18, species ca. 150 (4 genera, 19 species in the flora). Plants of this family are wind-pollinated (anemophilous). Ulmaceae are frequently divided into two subfamilies, Ulmoideae and Celtoideae; they are sometimes separated into two families, Ulmaceae and Celtidaceae (I. A. Grudzinskaya 1965). These subfamilial or familial distinctions are supported by flavonoid chemistry (D. E. Giannasi and K. J. Niklas 1977; D. E. Giannasi 1978), pollen morphology (M. Zavada 1983), and some anatomic structures (E. M. Sweitzer 1971). Typically the Ulmoideae have flavonols, strictly pinnately veined leaves, and dry fruits; the Celtoideae have glycoflavones, pinnipalmately veined leaves, and drupaceous fruits. Some genera (e.g., Zelkova, with pinnately veined leaves and drupaceous fruits) are intermediate, and various authors place them in different subfamilies. In this treatment Ulmus and Planera are considered part of the subfamily Ulmoideae; Celtis and Trema are in subfamily Celtoideae. Zelkova serrata is widely cultivated as an ornamental tree in North America, but it is not known to be naturalized in the flora. Chemical similarities between subfamilies include the presence of proanthocyanins with some tannins and scattered mucilaginous cells or canals. Additionally, members of the family share a strong tendency toward mineralization of the cell walls with calcium carbonate or silica and possess solitary or clustered crystals of calcium oxalate. Ulmaceae include trees and shrubs of horticultural importance. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 3. | FNA vol. 3, p. 368. | ||||||||||||
Parent taxa | Ulmaceae > Celtis | |||||||||||||
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Synonyms | C. occidentalis var. canina, C. occidentalis var. crassifolia, C. occidentalis var. pumila, C. pumila, C. pumila var. deamii | |||||||||||||
Name authority | Linnaeus: Sp. Pl. 2: 1044. (1753) | Mirbel | ||||||||||||
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