Tsuga Canadensis (Eastern hemlock)

Scientific Name
Tsuga canadensis

Trade Name
Eastern hemlock

Family Name
Pinaceae

Common Names
American hemlock, Canada hemlock, Canadian hemlock, Common hemlock, Eastern hemlock, Hemlock, Hemlock spruce, Spruce pine, White hemlock

Regions of Distribution
North America

Countries of Distribution  [VIEW MAP]
Canada, United States

Common Uses
Agricultural implements, Beams, Boxes and crates, Building construction, Building materials, Cabin construction, Casks, Concrete formwork, Construction, Decks, Domestic flooring, Factory construction, Factory flooring, Flooring, Form work, Foundation posts, Framing, Heavy construction, Joinery, Joists, Light construction, Millwork, Packing cases, Pallets, Piling, Plywood, Poles, Porch columns, Pulp/Paper products, Pulpwood, Rafters, Railroad cars, Railroad ties, Roofing, Rough construction, Shakes, Shingles, Siding, Sub-flooring, Toys, Vehicle parts

Environmental Profile

Believed to be threatened by the Hemlock Woolly Adelgid

Distribution Overview
Eastern hemlock occurs in Canada, from Nova Scotia to southwestern Ontario. In the United States it is distributed in Alabama, Connecticut, Delaware, Georgia, Kentucky, Massachusetts, Maryland, Maine, Michigan, North Carolina, Great Smoky Mountain National Park, Minnesota, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Virginia, Vermont, Indiana, Wisconsin, and West Virginia. The tree grows in acid soils in moist cool valleys and rock outcrops, particularly north-facing bluffs. It is often found in pure stands.

Heartwood Color

Wood often has a red tinge in the latewood region of the growth ring

Sapwood Color

Grain

Texture

Growth rings are distinct, but not conspicuous.

Natural Growth Defects
Compression wood, shakes and cross-grain are common.

Natural Durability

Eastern hemlock has very little natural resistance to decay and should not be used under conditions that promote decay. The wood is reported to turn light gray with a moderate sheen upon prolonged exposure to the weather.

Odor

Kiln Schedules

Drying Defects

Wetwood and compression wood may cause degrades such as, uneven moisture content, warp, and ring shakes during drying.

Ease of Drying

Tree Size

This shade and ornamental tree is the state tree of Pennsylvania

Product Sources
Supplies of hemlock in the United States and Canada are, however, excellent. The wood compares favorably with Lodgepine pine (Pinus contorta) for certain applications, but costs about half the price of lodgepole pine.

Gluing

The timber is reported to bond well with various types of common commercial adhesives.

Nailing

Planing

Resistance to Impregnation

Resistance to Splitting

Response to Hand Tools

Veneering Qualities

Painting

Staining

Strength Properties

Hemlock is described as one of the hardest softwoods, and is usually available in long clear lengths. Compared to Western hemlock, Eastern hemlock is brashy and brittle, and does not respond as well to machining operations

Numerical Data

References
Boone, R.S., C.J. Kozlik, P.J. Bois and E.M. Wengert. 1988. Dry Kiln Schedules for Commercial Woods: Temperate and Tropical. United States Department of Agriculture, Forest Service, Forest Products Laboratory, General Technical Report FPL-GTR-57, Madison, Wisconsin.

Brisbin, R.L.,1970,American Woods – Eastern Hemlock,USDA, Forest Service American Woods FS-239

Brown, H.P. and Panshin, A.J.,1940,Commercial Timbers of the United States Their structure, identification,,properties and uses,McGraw-Hill, London

Brown, W.H.,1978,Timbers of the World: – No.7 North America,TRADA

Canadian Forestry Service. 1981. Canadian Woods – Their Properties and Uses. Third Edition. E.J. Mullins and T.S. McKnight, Editors. Published by University of Toronto Press, Toronto, Canada.

Dallimore, W. and Jackson, A. Bruce,1966,A Handbook of Coniferae and Ginkgoaceae Fourth Ed. Revised by S.G.,Harrison,Edward Arnold (Publishers) Ltd. London

Forest Products Research Laboratory, U.K.,1945,A Handbook of Empire Timbers,Department of Scientific and Industrial Research Forest Products Research

Howard, A.L.,1948,A Manual of Timbers of the World.,Macmillan & Co. Ltd. London 3rd ed.

I.U.F.R.O.,1973,Veneer Species of the World,Assembled at F.P.L. Madison on behalf of I.U.F.R.O. Working Party on,Slicing and Veneer Cutting

Kaiser, J. 1990. Wood of the Month – Hemlock: The Hardworking Softwood. Wood of the Month Annual, Supplement to Wood and Wood Products, September, 1990. Page 12A.

Little, E.L. 1980. The Audubon Society Field Guide to North American Trees – Eastern Region. Published by Arthur A. Knopf, New York.

Markwardt, L.J., Wilson, T.R.C.,1935,Strength and related properties of woods grown in the United States,U.S.A. Department of Agriculture Technical Bulletin,No.479

Mullins, E.J. and McKnight, T.S.,1981,Canadian Woods Their Properties and Uses,University of Toronto Press 3rd Edition

Panshin, A.J. and C. deZeeuw. 1980. Textbook of Wood Technology, 4th Edition. McGraw-Hill Series in Forest Resources. McGraw-Hill Book Company, New York.

Patterson, D.,1988,Commercial Timbers of the World, 5th Edition,Gower Technical Press

Record, S.J., Hess, R.W.,1943,Timbers of the New World,Yale University Press

Titmuss, F.H.,1965,Commercial Timbers of the World,Technical Press Ltd., London, 3rd edition

U.S.D.A. Forest Service,1974,Wood Handbook,U.S.A. Department of Agriculture, Forest Service Handbook,72

USDA. 1987. Wood Handbook – Wood as an Engineering Material, Forest Service, Agriculture Handbook No. 72, Forest Products Laboratory, Madison, Wisconsin.

USDA. 1988. Dry Kiln Operators Manual, Preliminary Copy. Forest Service, Forest Products Laboratory, Madison, Wisconsin.

Wolcott, G.N.,1950,An Index to the Termite Resistance of Woods,Agricultural Experimental Station, University of Puerto Rico Bulletin,No.85