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Clicking any heading in the main data area (at right) will scroll the page back to this top position. Use the following links to jump to the associated section in the main data. Common Names Common Uses Countries of Distribution Distribution Overview Drying Defects Ease of Drying Environmental Profile Family Name Gluing Grain Heartwood Color Kiln Schedules Nailing Natural Durability Natural Growth Defects Numerical Data Odor Painting Planing Product Sources References Regions of Distribution Resistance to Impregnation Resistance to Splitting Response to Hand Tools Sapwood Color Scientific Name Staining Strength Properties Texture Trade Name Tree Size Veneering Qualities 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 Abundant/Secure May be rare in some parts of its range Generally widespread, secure, and abundant within most of its range Data source is Nature Conservancy 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 Brown Red Pale brown Red Yellow to golden-yellow to orange Reddish brown White to cream Light brown Buff Wood often has a red tinge in the latewood region of the growth ring Sapwood Color Brown Red Paler than heartwood Same as heartwood Color not distinct from heartwood Grain Figure Growth rings (figure) Other (figure) Interlocked Crossed Distinct (figure) Spiral Clear growth rings (figure) Other figure Twisted Spiral Interlocked Generally straight, but may be somewhat uneven Distinct and very fine figure Texture Coarse Medium coarse to coarse Medium Fine Growth rings are distinct, but not conspicuous. Natural Growth Defects Compression wood, shakes and cross-grain are common. Natural Durability Non-durable Non durable Very little natural resistance Susceptible to attack from termites (Isoptera) Pinworms (ambrosia beetles) are commonly present Durable 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 No specific taste Freshly milled wood has a sour or rancid odor Kiln Schedules T12 - C4 (4/4); T11 - C3 (8/4) US Schedule K (4/4) United Kingdom/T12 - C4 (4/4); T11 - C3 (8/4) US Schedule K (4/4) United Kingdom Drying Defects Severe twisting/warping Wetwood and compression wood may cause degrades such as, uneven moisture content, warp, and ring shakes during drying. Ease of Drying Rapidly Fairly Easy Difficult Moderate Moderate shrinkage Tree Size Tree height is 30-40 m Tree height is 40-50 m Tree height is 50-60 m Tree height is 60-70 m Tree height is greater than 70 m 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 Fair to Good Results Fairly Easy to Very Easy Easy to glue The timber is reported to bond well with various types of common commercial adhesives. Nailing Holds satisfactorily Tends to split during nailing Holds nails well Planing Difficult to plane Planes to a poor finish Resistance to Impregnation Heartwood is resistant Heartwood is moderately resistant Difficult to treat with preservatives Resistance to Splitting Poor Response to Hand Tools Moderate working qualities Difficult to machine Poor machining qualities Easy to machine Veneering Qualities Drying degrade is often moderate to severe, with collapse, buckles, and splilts Diifficult to veneer Painting Satisfactory results Fairly good painting properties Staining Finish is generally good Strength Properties Density (dry weight) = 23-30 lbs/cu. ft. Work to Maximum Load = very low Modulus of Elasticity (stiffness) = very low Max. crushing strength = medium Hardness (side grain) = very soft Bending strength (MOR) = low Shrinkage, Radial = very small Shearing strength (parallel to grain) = very low Shrinkage, Tangential = very small Shrinkage, Tangential = moderate Max. crushing strength = low Density (dry weight) = 31-37 lbs/cu. ft. Bending strength (MOR) = very low 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 Item Green Dry English Bending Strength 5958 8706 psi Crushing Strength 372 627 psi Density 26 lbs/ft3 Hardness 412 lbs Impact Strength 22 18 inches Maximum Crushing Strength 3359 5720 psi Shearing Strength 980 psi Static Bending 3430 5684 psi Stiffness 1081 1216 1000 psi Work to Maximum Load 6 7 inch-lbs/in3 Specific Gravity 0.37 0.39 Weight 26 23 lbs/ft3 Radial Shrinkage 2 % Tangential Shrinkage 6 % Volumetric Shrinkage 10 % Item Green Dry Metric Bending Strength 418 612 kg/cm2 Crushing Strength 26 44 kg/cm2 Density 416 kg/m3 Hardness 186 kg Impact Strength 55 45 cm Maximum Crushing Strength 236 402 kg/cm2 Shearing Strength 68 kg/cm2 Static Bending 241 399 kg/cm2 Stiffness 76 85 1000 kg/cm2 Work to Maximum Load 0.42 0.49 cm-kg/cm3 Specific Gravity 0.37 0.39 Weight 416 368 kg/m3 Radial Shrinkage 2 % Tangential Shrinkage 6 % 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