Hemlock

Chinese hemlock Tsuga Chinensis

Description

Any of several evergreen conifer trees of the genus Tsuga. Hemlock trees are native to North America and Asia. These softwood trees produce a timber that is stiff and splinters easily. The light yellow wood is primarily used for paper pulp, boxes, and crates. The bark extract from the eastern hemlock, T. canadensis, and western hemlock, T. heterophylla, trees is high in tannins containing up to 22%. The extract is also used as a dye to produce colors ranging from a pinkish tan to a dark gray. Native Americans used hemlock to dye basketry and blankets.

Synonyms and Related Terms

eastern hemlock (Tsuga canadensis -also called Canadian hemlock and hemlock spruce); western hemlock (Tsuga heterophylla -also called hemlock fir and Prince Albert's fir); European hemlock (Conium maculatum-also called poisonous hemlock); Japanese hemlock (Tsuga diversifolia); Siebold's hemlock (Tsuga sieboldii); pruche du Canada (Fr.); spruce pine

Density	25-35 ppcf

Hazards and Safety

The water soluble extract of the poisonous hemlock contains coniine and is toxic.

Authority

• G.S.Brady, G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 394

• Palmy Weigle, Palmy Weigle, Ancient Dyes for Modern Weavers, Watson-Guptill Publications, New York, 1974

• F. H. Titmuss, F. H. Titmuss, Commercial Timbers of the World, The Technical Press Ltd., London, 1965

• Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996

• Encyclopedia Britannica, http://www.britannica.com Comment: "hemlock." Encyclopdia Britannica. 2004. Encyclopdia Britannica Premium Service. 3 Dec. 2004 .

• Edward Reich, Carlton J. Siegler, Edward Reich, Carlton J. Siegler, Consumer Goods: How to Know and Use Them, American Book Company, New York City, 1937

• Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976

• Random House, Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997

• The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998