Alaska paper birch1

Betula neoalaskana
Alaska paper birch Alaska paper birch

Alaska paper birch is also known as Alaska white birch or Alaska paper birch. A small tree, often with many stems, up to 15 metres tall. Crown narrow, oval. Branches slender, stiffly upright, some with drooping tips. Similar to, but smaller than, paper birch (Betula papyrifera). 

Leaves
Triangular to broadly oval, about 4 to 7 centimetres long, and doubly toothed; shiny dark green on top, light yellowish-green with tiny resin dots underneath, almost hairless; tip long-tapered, sharp-pointed; base broadly wedge-shaped, with a smooth margin; teeth often gland-tipped; veins four or five per side, each ending in a tooth, with three to five smaller intervening teeth. Leaf stalks are approximately twice as long as those of Betula papyrifera.

Buds
Blunt, greenish-brown, resinous, slightly hairy.

Alaska paper birch leaves
Twigs
Slender, bright reddish-brown, with an abundance of fine short hairs; covered with resin glands, sometimes large and crystalline and dense enough to conceal the twig surface.

Flowers
Pollen catkins 2.5 to 4 centimetres long at pollination; seed catkins 1 to 2 centimetres.

Fruit
Mature seed catkins about 2.5 to 3.5 centimetres long, blunt-tipped, drooping or slightly spreading from the dwarf shoots. Nutlets twice as long as broad; wings much wider than the nutlet. Scales with two lateral lobes pointing away from the central lobe or curved slightly downward. Catkin disintegrates, shedding fruits and scales.

Alaska paper birch catkins
Alaska paper birch bark Bark
Thin, smooth, dark reddish-brown when young, becoming creamy white or slightly pinkish with age; peels off in papery layers (but not as freely as paper birch).

Where to find Alaska paper birch
A northwestern North American tree species, this species has an extensive range from northwestern Ontario to western Alaska. In British Columbia, it is confined to the northeastern portion of the province and the northern border area with the Yukon Territory.

Habitat
Alaska paper birch characteristically occurs on bogs and poorly drained soils; in pure stands or mixed with other species, especially black spruce (Picea mariana). On better drained sites in northeastern British Columbia it is commonly found in association with white spruce (Picea glauca).

Uses
Similar to the uses for paper birch (Betula papyrifera).

Where to find western Alaska paper birch

Notes
This species can be easily confused with Betula papyrifera. The key to differentiating the two species is a close examination of the twigs. Betula neoalaskana twigs are densely covered in bumpy resin glands.

Erratum: this information on the Alaska paper birch was added October 2003 to the on-line version of the Tree Book and is not available in the printed version or any other version.

1 Majority of information and all images (except location map) are copied with permission from Trees in Canada.
Farrar, J.L. , Trees in Canada. 1995. Canadian Forestry Service; Fitzhenry & Whiteside Limited, Markham, Ontario.

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