Betula pendula |
Betula papyrifera |
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bouleau pleureur, European birch, European weeping birch, European white birch, silver birch, weeping birch |
bouleau blanc, bouleau à papier, canoe birch, paper birch, western paper birch, white birch |
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Habit | Trees, to 25 m; trunks usually several, crowns spreading. | Trees, to 30 m, usually 20 m or shorter; trunks often single, sometimes 2 or more, mature crowns narrowly round. |
Bark | of mature trunks and branches creamy to silvery white, smooth, exfoliating as long strands; lenticels dark, horizontally expanded. |
of young trunks and branches dark reddish brown, smooth, in maturity creamy to chalky white or pale to (infrequently) dark brown, readily exfoliating in paper-thin sheets; lenticels pale, horizontal, in maturity dark, much expanded, horizontal. |
Branches | pendulous; twigs glabrous, usually dotted with small resinous glands. |
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Twigs | without strong odor and taste of wintergreen, slightly to moderately pubescent, infrequently with scattered, small, resinous glands. |
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Leaf | blade broadly ovate to rhombic with 5–18 pairs of lateral veins, 3–7 × 2.5–5 cm, base cuneate, rarely truncate, margins coarsely and sharply doubly serrate, apex acuminate; surfaces abaxially glabrous to sparsely pubescent, covered with minute, resinous glands. |
blade ovate with 9 or fewer pairs of lateral veins, 5–9(–12) × 4–7 cm, base rounded, cuneate, or truncate, margins sharply to coarsely or irregularly doubly serrate or serrate-dentate, apex acute to short-acuminate; surfaces abaxially sparsely to moderately pubescent, often velutinous along major veins and in vein axils, covered with minute, resinous glands. |
Infructescences | erect to nearly pendulous, cylindric, 2–3.5 × 0.6–1 cm, shattering with fruits in fall; scales adaxially sparsely pubescent, lobes diverging at middle, central lobe obtuse, much shorter than lateral lobes, lateral lobes broad, rounded, extended. |
pendulous, cylindric, 2.5–5 × 0.6–1.2 cm, readily shattering with fruits in late fall; scales pubescent to glabrous, lobes diverging at or proximal to middle, central lobe narrowly elongate, obtuse, lateral lobes about equal in length to central lobe but several times broader, strongly divergent, held nearly at right angles to axis. |
Samaras | with wings much broader than body, broadest near center, extended beyond body apically. |
with wings as broad as or slightly broader than body, extended nearly beyond body apically. |
2n | = 28, 56. |
= 56, 70, 84. |
Betula pendula |
Betula papyrifera |
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Phenology | Flowering late spring. | Flowering late spring. |
Habitat | Abandoned plantings, roadsides, edges of bogs, waste places | Moist, ± open, upland forest, especially on rocky slopes, also sometimes in swampy woods |
Elevation | 0–350 m (0–1100 ft) | 300–900 m (1000–3000 ft) |
Distribution |
CT; MA; NH; NY; OH; PA; VT; WA; BC; MB; ON; Europe; Asia
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AK; CO; CT; IA; ID; IL; IN; MA; ME; MI; MN; MT; ND; NE; NH; NJ; NY; OR; PA; RI; SD; VA; VT; WA; WI; WY; AB; BC; MB; NB; NF; NS; NT; ON; PE; QC; SK; YT; SPM
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Discussion | The Eurasian weeping birch (Betula pendula) is extensively cultivated throughout the temperate range of the flora, and it has been known to persist or to become locally naturalized in several areas, particularly in the Northeast. In vegetative features it resembles B. populifolia Marshall, to which it is closely allied; it can easily be distinguished from the latter by its peeling bark, as well as by its mostly pubescent leaves with somewhat shorter, acuminate apices. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Betula papyrifera is a well-known tree of the northern forest with its paper-thin, white, peeling bark. The bark, which has a high oil content and is consequently waterproof, was used for a wide variety of building and clothing purposes by the American Indians, including the covering of the familiar birch bark canoe. It is still used for various purposes, including basketmaking, in Canada and Alaska. Variants having more or less close, dark brown bark (B. papyrifera var. commutata) occur locally throughout the wide range of this species; this characteristic appears to be largely environmentally caused. The species is an important successional tree, coming up readily after fires, logging, or the abandonment of cultivated land. The relatively soft, whitish wood is used extensively for such items as clothespins, spools, ice cream sticks, and toothpicks, as well as for pulpwood for paper. Betula papyrifera is the state tree of New Hampshire. Native Americans use Betula papyrifera medicinally in enemas, to shrivel the womb, to alleviate stomach cramps and pain, and as a tonic (D. E. Moerman 1986). Betula ×sandbergii Britton is a fairly common hybrid, occurring where the ranges of the parents (B. papyrifera Marshall and B. pumila Linnaeus) come into contact. In most vegetative features it is intermediate between the parental conditions (K. E. Clausen 1963; C. O. Rosendahl 1928). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 3. | FNA vol. 3. |
Parent taxa | Betulaceae > subfam. Betuloideae > Betula | Betulaceae > subfam. Betuloideae > Betula |
Sibling taxa | ||
Synonyms | B. verrucosa | B. alba var. papyrifera, B. papyracea, B. papyrifera var. commutata, B. papyrifera var. elobata, B. papyrifera var. macrostachya, B. papyrifera var. pensilis, B. papyrifera var. subcordata |
Name authority | Roth: Tent. Fl. Germ. 1: 405. (1788) | Marshall: Arbust. Amer., 19. (1785) |
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