Hemlock: the graceful conifer of the West.

The name hemlock may remind some of the poison. However, the hemlock tree is not poisonous like the herb. This tree had nothing to do with the weed that Socrates allegedly ingested before he died. Rather, it may be named hemlock because of the similarity in scent when the foliage is crushed. Tsuga, the genus name, is Japanese for hemlock. Poisonous hemlock belongs to the parsley family Umbelliferae and is classified as Consium maculatum.

Hemlock is known as a resin-free wood. Its has a pale brown heartwood with a darker colored latewood band that gives it a purple cast. Short purple lines on some wood that is plain sawn is due to the easily seen growth marks of some trees. Hemlock is a lustrous wood and improves with age and use.

If you are looking for hemlock in the western United States and Canada, it is likely that you will find it growing with its companions - Douglas fir, western red cedar, and Sitka spruce. But in some areas of the Northwest where the climate is ideal, western hemlock dominates.

In his book "A Natural History of Western Trees," Donald Culross Peattie writes, "Hemlock is not one of the gigantic species, though its 100 to 150 feet of height would be considered so in the silva of the eastern states. But it is abundant, almost omnipresent in its range. Hemlock seems to fill all the spaces not forcibly occupied by other trees."

According to the Western Wood Products Assn., 66.8 percent of all hemlock sawn in 1993 was made into dimension products and accounted for 12.9 percent of all dimension lumber produced in the west. More than 1.6 million of board feet of hemlock was produced in 1993.

Western hemlock is also regarded as one of the prime North American timbers and is exported all over the world for a variety of uses. Because of its size, it is used for building construction: joists, rafters, studding, doors, exterior and interior joinery, flooring and suspended ceilings. It is also a popular turnery wood. Some hemIock logs are sliced for veneer to make paneling or plywood. Hemlock is also used to make packing crates and pallets. Hemlock also can produce high quality newsprint. Treated, the wood can be used for railroad sleepers.

Hemlock will work easily with hand or machine tools. The wood does have knots and these can be brittle. Pre-boring is recommended for nailing, especially near the ends of the boards, which could be dry and brittle. The wood can be glued, stained and painted or otherwise finished easily. Seasoning can be tricky. The wood's natural high moisture content can be difficult to extract when the wood is thick. Slow drying is recommended. The wood has small movement in service. Hemlock timber is non-durable and is susceptible to insect attack.

No longer considered a "weed tree"

Hemlock, from the species Tsuga heterophylla, is a softwood. Its growth range is Alaska, northern Washington, Idaho, and Canada, especially British Columbia. It flourishes on the coastline from Alaska all the way south to central California and grows east to Montana and Idaho. It thrives in Oregon, Alaska and Washington and is the state tree of Washington. It has been introduced to the United Kingdom where it grows successfully. Hemlock trees also grow in Japan, China and India.

As valuable a tree as hemlock is, there was a time when loggers avoided it, thinking it was similar to the eastern hemlock, Tsuga canadensis, which is a soft, brittle wood. The tree was even known as a "weed tree," according to Peattie, adding that old time loggers would try to pass the wood off as Douglas fir if cut by mistake. However, near the end of the 1800s, someone took another look at the wood and realized its value. According to Peattie, people discovered, "It is strong, fine-textured, straight-grained, stiff, free of pitch, saws off easily without splintering, and holds nails well." By the mid-1930s, western hemlock was widely used in woodworking.

Also increasing hemlock's usage was the discovery that it produced paper pulp that rivaled the quality of the slow growing spruces. The alpha cellulose from hemlock can also be used to produce cellophane, rayon yarns and plastics. Because it grows so rapidly, hemlock stands are four times as plentiful as Sitka spruce, which is also used to make paper pulp.

A dominant presence

Western hemlock's "stock" has risen dramatically from its earliest association as the weed wood. While the most common heights are in the 150 to 190 foot range, some hemlocks can grow as tall as 270 feet. In addition to western hemlock, other hemlocks include eastern hemlock, white hemlock, Carolina hemlock, mountain hemlock, southern Japanese hemlock, northern Japanese hemlock, Chinese hemlock and Himalayan hemlock. Japanese hemlock is Tsuga sieboldii and Tsuga diversifola, Tsuga chinensis and Tsuga yunnanensis grow in China. Their wood is paler than western hemlock and is compared more often to eastern hemlock, which is sometimes called white hemlock.

Hemlocks have blunt, soft needles which are joined to the twig by small woody stacks that remain on the twig when the needles fall off. The hemlock seeds, which are released from the cones of the tree, faLL to the ground or are carried by birds or the wind and sprout easily, another reason why this fast growing tree dominates the forests.

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Family Names

Tsuga heterophylla of the Family Pinaceae

Other Names

Western hemlock, Pacific hemlock, Alaska pine, British Columbian hemlock, hemlock spruce

Height/Weight

Height ranges from 150 to 200 feet with diameters from 6 to 8 feet. Weight is 30 pounds per cubic foot.

Properties

Initial high moisture content demands careful drying or wood will surface check. Medium bending and crushing strength, low hardness and stiffness, moderate steam bending rating.