Tsuga

These evergreen trees are commonly known as Hemlock or Hemlock Spruce. Hemlocks are found wild in North America, the Himalayas, Japan and China. Most of these trees are hardy and as other Conifers (cone-bearing tree), need a fairly clean atmosphere to survive. Hemlock can be distinguished from other Conifers by its flat, linear, dark green leaves, which have two long, whitish lines on their lower surfaces. Each leaf is attached to a little woody stem that remains on the twig after the leaves fall. Leaves also grow along the upper surfaces of the twigs. The leaves will grow up to �-inch in length. The have rounded or slightly notched tips. The cones are pendant and grow � to � of an inch long. They mature at the end of the first season, but often stay on the twigs during the winter. This tree can grow over 80 feet in height with a diameter up to 3 feet. The Hemlock is a very handsome shade or ornamental tree and makes a nice hedge since it takes to pruning well. Hemlock's bark is high in tannic acid, which was greatly used in tanning hides. The wood of this evergreen tree is hard, brittle and not very durable; it is used for rough lumber, building construction, boxes, crates, and as pulpwood. There is a false conception that the Hemlock is poisonous, however, the twigs and leaves have been used by Indians and woodsmen to brew a tea. The young growth is said to have been an ingredient in old-fashioned root beer. The Poison Hemlock was taken from a completely different plant, a member of the Parsley family. The Mountain Hemlock, T. Mertensiana, is a lovely tree that often exceeds 100 feet in height.. It has soft, bluish-green leaves and its cones are usually 1� to 2 inches long. It is found from Alaska to California. T. heterophylla, the Western American Hemlock grows up to 220 feet high. It is pyramidal in growth and the almost horizontal branches divide into many fine branchlets, covered with small, dark green leaves.

Pot Cultivation

Hemlocks prefer cool, moist places. It is often found along streams and the edges of bogs and swamps, or on steep northward facing slopes. These trees will tolerate partial shade. Hemlocks need plenty of room to grow; they shouldn't be crowded by other trees during their development or at maturity. Not much pruning is necessary for these trees unless you want the lower part of the trunk is to be clear. If this is desired, do not remove too many of the lower branches all at once, instead take only a few branches each year until the desired height of clean trunk is attained. When desired for hedge plants, young Hemlocks, no larger than 1 to 3 feet high, should be used. Place them in deeply dug soil that has been enriched generously with compost, leaf mold, rotted manure or some other bulky, decayed organic matter. Set them no more than 18 to 24 inches apart. Pruning should be done each spring before new growth begins and if desired, once again about mid-summer. Established hedges will benefit from a mulch of manure or a dressing of a complete fertilizer each spring.

Propagation

Trees may be increased by sowing seeds outside in the spring or in containers of light soil. Young plants may be grown in nursery rows until they are large enough to be placed in their permanent positions. It is better to set rather small trees in their permanent spots than to try and transplant larger ones, although, if care is taken, quite large trees can be moved. It is better to transplant in early fall or spring. Hybrids that won't come true from seed should be increased by cuttings. These are made from half-ripe shoots and inserted in a propagating case in a greenhouse in late summer or fall. Hybrids may also be increased by grafting on stocks of their types in the winter.

T. Sieboldii	T. chinensis

VARIETIES

• T. canadensis (Eastern American Hemlock) & var. pendula (Sargent's Weeping Hemlock), albo-spica, microphylla, macrophylla, Fremdii, nana & gracilis.
• T. caroliniana (Carolina Hemlock) & var. compacta;
• T. Mertensiana (Mountain Hemlock) & var. argentea;
• T. heterophylla (Western American Hemlock);
• T. diversifolia (Japanese Hemlock);
• T. Sieboldii;
• T. dumosa (Himalayan Hemlock);
• T. chinensis;
• T. yunnanensis.