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Hemlocks — Part 2

In hedges the young trees are thrifty, and even the shears cannot subdue the grace that renews every spring the delicate, flexible new shoots. They seem more like wavering tendrils of a vine than branches of a sturdy conifer.

The seeds of hemlock are slow to germinate on burned-over ground, but in the leaf mould, overshadowed by larger trees, they start in great numbers. For four or five years they average scarcely an inch a year, but they produce a good root system. After this they rapidly mount upward to independence. They supply a valuable protective cover for seedling white pines. The two species grow together often in large forests. Canada offers the best soil and climate for hemlock. It requires cool air with rich, loamy soil, moist but well drained. It is found plentifully in our Northern and Eastern States, and follows the mountains to Alabama.

Hemlock wood is coarse and splintery, likely to be crossgrained and full of knots. It warps in seasoning, and wears rough; moreover, it is brittle and weak. It has two cardinal virtues that adapt it for railroad ties and the large beams used in the frames of houses and barns. Hemlock timbers are stiff, and the wood has a firm grip on nails and spikes. The wood never loosens its hold upon the nail, nor does it split in nailing. Hemlock is used for the outside of cheap buildings, but it finds its greatest usefulness as the unseen props of a house, its faults covered up by woods of more uniform and attractive appearance.

The bark of hemlock abounds in tannin, which makes it a standard tan bark. It is not uncommon to see young hemlock woods felled and stripped for the bark alone. The waste of the wood is very bad forestry, but as hemlock is poor fuel, and ugly to saw and split, sometimes cordwood costs more to cut and haul than it brings in market. If the trees were left to attain proper age for mill stuff, the lumber would be salable, and there would be a much larger crop of bark.

The logs are cut for tan bark only in the summer. The bark "slips" from May until August. After that, peeling is impossible. The logs are girdled every four feet from the butt well up into the tops. Two or three cuts are made at equal distances apart, lengthwise of the trunk. This makes of each four-foot cylinder of bark two or three rectangular sheets, easily removed with a special bark-peeling tool. The sheets are stacked on end to dry, and are later laid in solid four-foot piles to be measured by the cord. The hemlock bark is usually mixed with some oak bark at the tanneries. A side of sole leather tanned with hemlock alone is a brighter red than is desired. The oak darkens it. Dye works consume some hemlock bark in making certain shades of brown.

Oil of hemlock is distilled from the leaves. "Canada pitch," formerly much used as a drug, is extracted from leaves and knots. In the practice of the Indians, the bark of young hemlocks, boiled and pounded to a paste, made a poultice for sores and wounds. Josselyn noted also: "The turpentine thereof is singularly good to heal wounds and to draw out the malice of any Ach, rubbing the place therewith." The antiseptic action of the oil and resin was recognised then as now.

The Carolina Hemlock (Tsuga Caroliniana, Engelm.) occurs most abundantly about the headwaters of the Savannah River in South Carolina. It grows on the mountains from Virginia into Georgia, and was long confused with the common Northern hemlock by botanists and other observers. It has found favour with landscape gardeners, because it is more graceful though more compact than T. Canadensis. Its leaves are longer, darker green above, and a more pronounced white underneath. It rarely grows over 70 feet high, but has a better head when old than its Northern relative. It is a hardy, handsome tree in New England parks, and its popularity is growing.

Western Hemlock (Tsuga heterophylla, Sarg.)--Noble pyramidal tree, 100 to 200 feet high, 6 to 10 feet in diameter, with drooping, horizontal branches and feathery tip. Bark reddish brown, with broad, scaly, interrupted ridges and shallow fissures. Wood tough, durable, hard, light, strong, brown. Buds brown, ovate, small. Leaves grooved on top, lustrous, pale below, rounded at tip; petioles slender. Flowers: monoecious, terminal, solitary; staminate yellow; pistillate purple. Fruit oval, pointed cones 1 inch long; scales often constricted in the middle, broad, thin. Preferred habitat, moist valleys and uplands from tidewater to 6,000 feet elevation. Distribution, southeastern Alaska to Cape Mendocino in California; east to Montana and Idaho. Uses: Wood used chiefly in building; bark for tanning. Indians eat a cake made from the inner bark. Successfully used for ornamental planting in Europe. Not hardy in our Eastern States.