Alaska Birch
Encyclopedia
Betula neoalaskana or Alaska Birch, also known as Alaska Paper Birch or Resin Birch, is a species of birch
Birch
Birch is a tree or shrub of the genus Betula , in the family Betulaceae, closely related to the beech/oak family, Fagaceae. The Betula genus contains 30–60 known taxa...

 native to Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

 and northern Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

. Its range covers most of interior Alaska, and extends from the southern Brooks Range
Brooks Range
The Brooks Range is a mountain range in far northern North America. It stretches from west to east across northern Alaska and into Canada's Yukon Territory, a total distance of about 1100 km . The mountains top out at over 2,700 m . The range is believed to be approximately 126 million years old...

 to the Chugach Range in Alaska, including the Turnagain Arm and northern half of the Kenai Peninsula
Kenai Peninsula
The Kenai Peninsula is a large peninsula jutting from the southern coast of Alaska in the United States. The name Kenai is probably derived from Kenayskaya, the Russian name for Cook Inlet, which borders the peninsula to the west.-Geography:...

, easterward from Norton Sound
Norton Sound
Norton Sound is an inlet of the Bering Sea on the western coast of the U.S. state of Alaska, south of the Seward Peninsula. It is about 240 km long and 200 km wide. The Yukon River delta forms a portion of the south shore and water from the Yukon influences this body of water...

 into western Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....

, and north to Northwest Territories
Northwest Territories
The Northwest Territories is a federal territory of Canada.Located in northern Canada, the territory borders Canada's two other territories, Yukon to the west and Nunavut to the east, and three provinces: British Columbia to the southwest, and Alberta and Saskatchewan to the south...

 and southern Nunavut
Nunavut
Nunavut is the largest and newest federal territory of Canada; it was separated officially from the Northwest Territories on April 1, 1999, via the Nunavut Act and the Nunavut Land Claims Agreement Act, though the actual boundaries had been established in 1993...

.

This tree typically grows to 15-20 m tall, occasionally up to 25 m, and achieves a trunk diameter of 20-40 cm, rarely to more than 60 cm, and a narrow crown. It grows in a variety of habitats, from wetlands to ridgetops at altitudes of 100-1200 m. The mature bark
Bark
Bark is the outermost layers of stems and roots of woody plants. Plants with bark include trees, woody vines and shrubs. Bark refers to all the tissues outside of the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner...

 ranges widely in color, from pure white to red, yellowish, pinkish, or gray. Bark of twigs, seedlings, and saplings is dark, from reddish to almost black, and covered with resin glands. The leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....

 are triangular-ovate, 3-8 cm long and 2-6 cm broad, with a truncate base and an acuminate apex, and a double-serrated margin. The fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...

ing catkin
Catkin
A catkin or ament is a slim, cylindrical flower cluster, with inconspicuous or no petals, usually wind-pollinated but sometimes insect pollinated . They contain many, usually unisexual flowers, arranged closely along a central stem which is often drooping...

s are 2-4 cm long and about 1 cm broad.

Although it is diploid like its close relatives, the Eurasia
Eurasia
Eurasia is a continent or supercontinent comprising the traditional continents of Europe and Asia ; covering about 52,990,000 km2 or about 10.6% of the Earth's surface located primarily in the eastern and northern hemispheres...

n 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...

 and the eastern American Gray Birch
Gray Birch
Betula populifolia is a deciduous tree native to North America. It ranges from southeastern Ontario east to Nova Scotia, and south to Pennsylvania and New Jersey, with disjunct populations in Indiana, Virginia, and North Carolina. It prefers poor, dry upland soils, but is also found in moist...

, it frequently hybridizes with the hexaploid Paper Birch
Paper Birch
Betula papyrifera is a species of birch native to northern North America.-Description:...

; the hybrid is known as Betula × winteri. Hybrids also occur with American Dwarf Birch
American Dwarf Birch
Betula glandulosa, American Dwarf Birch, also known as Resin Birch or Shrub Birch, is a species of birch native to North America, occurring in arctic and cool temperate areas from Alaska east to Newfoundland and southern Greenland, and south at high altitudes to northern California and Colorado in...

, named Betula × uliginosa.
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