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Betula pubescens (Downy Birch; also known as White Birch, European White Birch or Hairy Birch) is a species of birch
Birch

Birch is the name of any tree of the genus Betula , in the family Betulaceae, closely related to the beech/oak family, Fagaceae....
, native and abundant throughout northern Europe
Europe

Europe is, conventionally, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally divided from Asia to its east by the water divide of the Ural Mountains, the Ural , the Caspian Sea, and by the Caucasus Mountains to the southeast....
, Iceland
Iceland

Iceland, officially the Republic of Iceland , is an island country located in the North Atlantic Ocean between mainland Europe and Greenland....
, northern Asia
Asia

Asia is the world's largest and most populous continent. It covers 8.6% of the Earth's total surface area and, with over 4 billion people, it contains more than 60% of the world's current human population....
 and also Greenland
Greenland

Greenland is a member country of the Kingdom of Denmark located between the Arctic Ocean and Atlantic Oceans, east of the Canadian Arctic Archipelago....
.

It is a deciduous
Deciduous

Deciduous means falling off at maturity or tending to fall off and is typically used in reference to trees or shrubs that lose their leaves seasonally and to the shedding of other plant structures such as petals after flowering or fruit when ripe....
 tree
TREE

TREE was a Boston hardcore punk band formed in the summer of 1990. They were active in the Boston music scene until disbanding in 2002....
 growing to 10-20 m tall (rarely to 27 m), with a slender crown and a trunk up to 70 cm (exceptionally 1 m) diameter, with smooth but dull grey-white bark
BARK

BARK was an early Electromechanics. BARK was built using standard phone relays, implementing a 32-bit binary machine and could perform addition in 150 ms and multiplication in 250 ms....
 finely marked with dark horizontal lenticel
Lenticel

A lenticel is an airy aggregation of cells within the structural surfaces of the stems, roots, and other parts of vascular plant. It functions as a pore, providing a medium for the direct exchange of gasses between the internal tissues and atmosphere, thereby bypassing the periderm, which would otherwise prevent this exchange of gases....
s.






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Betula pubescens (Downy Birch; also known as White Birch, European White Birch or Hairy Birch) is a species of birch
Birch

Birch is the name of any tree of the genus Betula , in the family Betulaceae, closely related to the beech/oak family, Fagaceae....
, native and abundant throughout northern Europe
Europe

Europe is, conventionally, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally divided from Asia to its east by the water divide of the Ural Mountains, the Ural , the Caspian Sea, and by the Caucasus Mountains to the southeast....
, Iceland
Iceland

Iceland, officially the Republic of Iceland , is an island country located in the North Atlantic Ocean between mainland Europe and Greenland....
, northern Asia
Asia

Asia is the world's largest and most populous continent. It covers 8.6% of the Earth's total surface area and, with over 4 billion people, it contains more than 60% of the world's current human population....
 and also Greenland
Greenland

Greenland is a member country of the Kingdom of Denmark located between the Arctic Ocean and Atlantic Oceans, east of the Canadian Arctic Archipelago....
.

It is a deciduous
Deciduous

Deciduous means falling off at maturity or tending to fall off and is typically used in reference to trees or shrubs that lose their leaves seasonally and to the shedding of other plant structures such as petals after flowering or fruit when ripe....
 tree
TREE

TREE was a Boston hardcore punk band formed in the summer of 1990. They were active in the Boston music scene until disbanding in 2002....
 growing to 10-20 m tall (rarely to 27 m), with a slender crown and a trunk up to 70 cm (exceptionally 1 m) diameter, with smooth but dull grey-white bark
BARK

BARK was an early Electromechanics. BARK was built using standard phone relays, implementing a 32-bit binary machine and could perform addition in 150 ms and multiplication in 250 ms....
 finely marked with dark horizontal lenticel
Lenticel

A lenticel is an airy aggregation of cells within the structural surfaces of the stems, roots, and other parts of vascular plant. It functions as a pore, providing a medium for the direct exchange of gasses between the internal tissues and atmosphere, thereby bypassing the periderm, which would otherwise prevent this exchange of gases....
s. The shoots are grey-brown and finely downy. The leaves
Leaf

In botany, a leaf is an above-ground plant Organ specialized for photosynthesis. For this purpose, a leaf is typically flat and thin, to expose the cells containing chloroplast to light over a broad area, and to allow light to penetrate fully into the tissues....
 are ovate-acute, 2-5 cm long and 1.5-4.5 cm broad, with a finely serrated margin. The flower
Flower

A flower, sometimes known as a bloom or blossom, is the reproduction structure found in flowering plants . The biological function of a flower is to mediate the union of male sperm with female ovum in order to produce seeds....
s are wind pollinated catkin
Catkin

A catkin or ament is a slim, cylindrical flower cluster, with inconspicuous or no petals, usually wind-pollination but sometimes insect pollinated ....
s, produced in early spring before the leaves. The fruit
Fruit

The term fruit has different meanings dependent on context, and the term is not synonymous in food preparation and biology. In botany, which is the scientific study of plants, fruits are the ripened Ovary of flowering plants....
 is a pendulous cylindrical aggregate 1-4 cm long and 5-7 mm diameter, which disintegrates at maturity releasing the individual seeds; these are 2 mm long with two small wings along the side.

It is closely related to, and often confused with, the Silver Birch
Silver Birch

Betula pendula, is a widespread European birch, though in southern Europe it is only found at higher altitudes. Its range extends into southwest Asia in the mountains of northern Turkey and the Caucasus....
 (B. pendula). Many North American
North America

North America is the northern continent of the Americas, situated in the Earth's northern hemisphere and almost totally in the western hemisphere....
 texts treat the two species as conspecific (and cause confusion by combining the Downy Birch's alternative vernacular name 'White Birch', with the scientific name B. pendula of the other species), but they are regarded as distinct species throughout Europe.

Downy Birch can be distinguished from Silver Birch in having smooth, downy shoots, which are hairless and warty in Silver Birch. The bark of the Downy Birch is a dull greyish white, whereas the Silver Birch has striking white papery bark with black fissures. The leaf margins also differ, finely serrated in Downy Birch, coarsely double-toothed in Silver Birch. They are also distinguished cytologically
Cytology

Cytology means "the study of cell s".Cytology is that branch of life science, which deals with the study of cells in terms of structure, function and chemistry....
, Silver Birch being diploid (with two sets of chromosomes), whereas Downy Birch is tetraploid (four sets of chromosomes). The two have differences in habitat
Habitat (ecology)

A habitat is an ecological or Natural_environment area that is inhabited by a particular animal or plant species. It is the natural environment in which an organism lives, or the physical environment that surrounds a species population....
 requirements, with Downy Birch more common on wet, poorly drained sites such as clays and peat bogs, and Silver Birch found mainly on dry, sandy soils.

Downy Birch extends farther north into the Arctic
Arctic

The Arctic is the region around the Earth's North Pole, opposite the Antarctica region around the South Pole. The Arctic includes the Arctic Ocean and parts of Canada, Greenland , Russia, the United States , Iceland, Norway, Sweden and Finland....
 than any other broadleaf tree. Specimens of the subarctic populations are usually small and very contorted, and are often distinguished as Arctic Downy Birch, Betula pubescens subsp. tortuosa. This subspecies is notable as being the only tree native to Iceland
Iceland

Iceland, officially the Republic of Iceland , is an island country located in the North Atlantic Ocean between mainland Europe and Greenland....
 and to Greenland
Greenland

Greenland is a member country of the Kingdom of Denmark located between the Arctic Ocean and Atlantic Oceans, east of the Canadian Arctic Archipelago....
, where large specimens can reach 5-6 m tall.