Canoe Birch White Birch Paper Birch
=Habitat and Range.=--Deep, rich woods, river banks, mountain slopes.
Canada, Atlantic to Pacific, northward to Labrador and Alaska, to
the limit of deciduous trees.
Maine,--abundant; New Hampshire,--in all sections, most common on
highlands up to the alpine area of the White mountains, above the range
of the yellow birch; Vermont,--common; Massachusetts,--common in the
western and
central sections, rare towards the coast; Rhode Island,--not
reported; Connecticut,--occasional in the southern sections, frequent
northward.
South to Pennsylvania and Illinois; west to the Rocky mountains and
Washington on the Pacific coast.
Var. minor, Tuckerman, is a dwarf form found upon the higher mountain
summits of northern New England.
=Habit.=--A large tree, 50-75 feet high, with a diameter of 1-3 feet;
occasionally of greater dimensions. The trunk develops a
broad-spreading, open head, composed of a few large limbs ascending at
an acute angle, with nearly horizontal secondary branches and a
slender, flexible spray without any marked tendency to droop.
Characterized by the dark metallic lustre of the branchlets, the dark
green foliage, deep yellow in autumn, and the chalky whiteness of the
trunk and large branches; a singularly picturesque tree, whether
standing alone or grouped in forests.
=Bark.=--Easily detachable in broad sheets and separable into thin,
delicately colored, paper-like layers, impenetrable by water, outlasting
the wood it covers. Bark of trunk and large branches chalky-white when
fully exposed to the sun, lustreless, smooth or ragged-frayed, in very
old forest trees encrusted with huge lichens, and splitting into broad
plates; young trunks and smaller branches smooth, reddish or grayish
brown, with numerous roundish buff dots which enlarge from year to year
into more and more conspicuous horizontal lines. The white of the bark
readily rubs off upon clothing.
=Winter Buds and Leaves.=--Buds small, ovate, flattish, acute to
rounded. Leaves simple, alternate, 3-5 inches long, two-thirds as wide,
dark green and smooth above, beneath pale, hairy along the veins,
sometimes in young trees thickly glandular-dotted on both sides; outline
ovate, ovate-oblong, or ovate-orbicular, more or less doubly serrate;
apex acute to acuminate; base somewhat heart-shaped, truncate or obtuse;
leafstalk 1-2 inches long, grooved above, downy; stipules falling early.
=Inflorescence.=--April to May. Sterile catkins mostly in threes, 3-4
inches long: fertile catkins 1-1-1/2 inches long, cylindrical,
slender-peduncled, erect or spreading; bracts puberulent.
=Fruit.=--Fruiting catkins 1-2 inches long, cylindrical, short-stalked,
spreading or drooping: nut obovate to oval, narrower than its wings;
combined wings butterfly-shaped, nearly twice as wide as long.
=Horticultural Value.=--Hardy throughout New England; prefers a
well-drained loam or gravelly soil, but does fairly well in almost any
situation; young trees rapid growing and vigorous, but with the same
tendency to grow irregularly that is shown by the black and yellow
birches; transplanted without serious difficulty; not offered by many
nurserymen, but may be obtained from northern collectors.
1. Leaf-buds.
2. Flower-buds.
3. Flowering branch.
4. Sterile flower, front view.
5. Fertile flower, front view.
6. Scale of fertile flower.
7. Fruiting branch.
8. Fruit.
=Alnus glutinosa, Medic.=