Betula pendula |
Betula michauxii |
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bouleau pleureur, European birch, European weeping birch, European white birch, silver birch, weeping birch |
bouleau de Michaux, Michaux's birch, Newfoundland dwarf birch |
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Habit | Trees, to 25 m; trunks usually several, crowns spreading. | Shrubs, spreading, dwarfed, to ca. 0.5 m. |
Bark | of mature trunks and branches creamy to silvery white, smooth, exfoliating as long strands; lenticels dark, horizontally expanded. |
dark brown, smooth, close; lenticels pale, inconspicuous, circular. |
Branches | pendulous; twigs glabrous, usually dotted with small resinous glands. |
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Twigs | without taste and odor of wintergreen, moderately to densely pubescent, not conspicuously resin-coated, without large, warty, 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 obovate–reniform, with 2–3 pairs of lateral veins, 0.5–1 × 0.5–1.2 cm, base cuneate, margins deeply crenate-dentate, apex broadly rounded to nearly truncate; surfaces abaxially usually glabrous. |
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. |
erect, short-cylindric, 0.5–1 × 0.5–0.8 cm, shattering with fruits in fall; scales unlobed (lateral lobes sometimes present but greatly reduced), glabrous. |
Samaras | with wings much broader than body, broadest near center, extended beyond body apically. |
with wings not apparent or reduced to narrow ridges. |
2n | = 28, 56. |
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Betula pendula |
Betula michauxii |
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Phenology | Flowering late spring. | Flowering late spring. |
Habitat | Abandoned plantings, roadsides, edges of bogs, waste places | Sphagnum bogs, around pools, and wet peaty meadows |
Elevation | 0–350 m [0–1100 ft] | 0–700 m [0–2300 ft] |
Distribution |
CT; MA; NH; NY; OH; PA; VT; WA; BC; MB; ON; Europe; Asia
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NF; NS; QC; 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.) |
This infrequent dwarf birch is distinguished from Betula nana mostly on the basis of its reduced infructescence scales and wetter habitat (J. J. Furlow 1984), characteristics that are also occasionally noted in B. nana. It perhaps might better be treated as a race of that species; in the absence of thorough study of this complex, however, it seems best to follow the traditional treatment (M. L. Fernald 1950c; J. Rousseau and M. Raymond 1950). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 3. | FNA vol. 3. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | B. verrucosa | B. terra-novae |
Name authority | Roth: Tent. Fl. Germ. 1: 405. (1788) | Spach: Ann. Sci. Nat., Bot., sér. 2, 15: 195. (1841) |
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