platyphylla)-Siberian silver birch (Siberia, Russian Far East, Manchuria, Korea, Japan, Alaska, western Canada) Betula platyphylla – ( Betula pendula var.Betula pendula – silver birch (widespread in Europe and northern Asia Morocco naturalized in New Zealand and scattered locations in US + Canada).Betula nana – dwarf birch (northern + central Europe, Russia, Siberia, Greenland, Northwest Territories of Canada)).Betula microphylla – (Siberia, Mongolia, Xinjiang, Kazakhstan, Kyrgyzstan, Uzbekistan). ![]() Betula megrelica – (Republic of Georgia).Betula medwediewii – Caucasian birch (Turkey, Iran, Caucasus).Betula maximowicziana – monarch birch (Japan, Kuril Islands).Betula humilis or Betula kamtschatica – Kamchatka birch platyphylla (northern + central Europe, Siberia, Kazakhstan, Xinjiang, Mongolia, Korea).Betula honanensis – (Henan Province in China).Betula gynoterminalis – (Yunnan Province in China).Betula grossa – Japanese cherry birch (Japan).Betula gmelinii – (Siberia, Mongolia, northeastern China, Korea, Hokkaido Island in Japan).Betula globispica – (Honshu Island in Japan).Betula fruticosa – (eastern Siberia, Russian Far East, northeastern China, Mongolia, Korea, Japan).Betula fargesii – (Chongqing + Hubei Provinces in China).Betula ermanii – Erman's birch (eastern Siberia, Russian Far East, northeastern China, Korea, Japan).Betula delavayi – (Tibet, southern China).Betula dahurica – (eastern Siberia, Russian Far East, northeastern China, Mongolia, Korea, Japan).Betula cylindrostachya – (Himalayas, southern China, Myanmar).Betula costata – (northeastern China, Korea, Primorye region of Russia).Betula corylifolia – (Honshu Island in Japan).Betula chinensis – Chinese dwarf birch (China, Korea).Betula chichibuensis – ( Chichibu region of Japan).Betula calcicola – (Sichuan + Yunnan Provinces in China).Betula browicziana – (Turkey and Georgia).Betula baschkirica – (eastern European Russia).Betula ashburneri – (Bhutan, Tibet, Sichuan, Yunnan Provinces in China).Betula alnoides – alder-leaf birch (China, Himalayas, northern Indochina).Betula albosinensis – Chinese red birch (northern + central China).Each scale bears a single small, winged nut that is oval, with two persistent stigmas at the apex.īirch leaves Birches native to Europe and Asia include The ovary is compressed, two-celled, and crowned with two slender styles the ovule is solitary. These scales bear two or three fertile flowers, each flower consisting of a naked ovary. ![]() The pistillate scales are oblong-ovate, three-lobed, pale yellow-green often tinged with red, becoming brown at maturity. The pistillate segments are erect or pendulous, and solitary, terminal on the two-leaved lateral spur-like branchlets of the year. Each calyx bears four short filaments with one-celled anthers or strictly, two filaments divided into two branches, each bearing a half-anther. Each scale bears two bractlets and three sterile flowers, each flower consisting of a sessile, membranous, usually two-lobed, calyx. The scales of the mature staminate catkins are broadly ovate, rounded, yellow or orange colour below the middle and dark chestnut brown at apex. They form in early autumn and remain rigid during the winter. ![]() Staminate catkins are pendulous, clustered, or solitary in the axils of the last leaves of the branch of the year or near the ends of the short lateral branchlets of the year. Once fully grown, these leaves are usually 3–6 millimetres ( 1⁄ 8– 1⁄ 4 in) long on three-flowered clusters in the axils of the scales of drooping or erect catkins or aments. The flowers are monoecious, opening with or before the leaves. The wood of all the species is close-grained with a satiny texture and capable of taking a fine polish its fuel value is fair. The buds, forming early and full-grown by midsummer, are all lateral, without a terminal bud forming the branch is prolonged by the upper lateral bud. Distinctive colors give the common names gray, white, black, silver and yellow birch to different species. The bark of all birches is characteristically marked with long, horizontal lenticels, and often separates into thin, papery plates, especially upon the paper birch. They differ from the alders ( Alnus, another genus in the family) in that the female catkins are not woody and disintegrate at maturity, falling apart to release the seeds, unlike the woody, cone-like female alder catkins. The fruit is a small samara, although the wings may be obscure in some species. They often appear in pairs, but these pairs are really borne on spur-like, two-leaved, lateral branchlets. The simple leaves are alternate, singly or doubly serrate, feather-veined, petiolate and stipulate. The front and rear view of a piece of birch barkīirch species are generally small to medium-sized trees or shrubs, mostly of northern temperate and boreal climates.
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