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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. Blunting Effect Boring Carving Comments Common Names Common Uses Countries of Distribution Cutting Resistance Distribution Overview Drying Defects Ease of Drying Environmental Profile Family Name Gluing Grain Heartwood Color Kiln Schedules Light-Induced Color Change Luster Mortising Moulding Movement in Service Nailing Natural Durability Numerical Data Odor Planing Polishing Product Sources References Regions of Distribution Resistance to Impregnation Response to Hand Tools Routing & Recessing Sapwood Color Scientific Name Screwing Staining Steam Bending Strength Properties Substitutes Synonyms Texture Toxicity Trade Name Tree Identification Tree Size Turning Veneering Qualities Scientific Name Robinia pseudoacacia Trade Name Black Locust Family Name Leguminosae Synonyms Robinia fragilis Common Names Acacia, Black locust, False acacia, Golden oak, Green locust, Loco, Locust, Post locust, Red locust, Robinia, Shipmast locust, Virginische schotendorn, White locust, Yellow locust Regions of Distribution North America Countries of Distribution  [VIEW MAP] Canada, United States Common Uses Agricultural implements, Bearings & bushings, Boat building (general), Boat building: framing, Boat building: planking, Boxes and crates, Bushing blocks, Cabinetmaking, Casks, Chairs, Crossties, Farm vehicles, Foundation posts, Fuelwood, Furniture, Heavy construction, Insulator pins, Joinery, Levers, Light construction, Lock gates, Machinery parts, Mine timbers, Novelties, Packing cases, Paneling, Piling, Poles, Posts, Propellers , Pulley sheaves, Pulley wheels, Railroad ties, Skids, Stakes, Tables, Trestle, Turnery, Utility poles, Vehicle parts, Veneer, Veneer: decorative, Wheel spokes, Wheels, Woodenware Environmental Profile Vulnerable Rank of relative endangerment based on number of occurences globally. May be rare in some parts of its range, especially at the periphery Demonstrably widespread, abundant, and secure globally Data source is Nature Conservancy Distribution Overview This species occurs in British Columbia, Nova Scotia, Ontario, Prince Edward Island, and Quebec in Canada. Its growth range in the United States includes Alabama, California, Colorado, Connecticut, Delaware, Florida, Georgia, Indiana, Kansas, Kentucky, Louisiana, Massachusetts, Maryland, Maine, Michigan, Minnesota, Missouri, Mississippi, Montana, North Carolina, Great Smoky Mountain National Park, Arkansas, Iowa, Illinois, Nebraska, New Hampshire, New Jersey, New Mexico, Nevada, New York, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Virginia, Vermont, Washington, Wisconsin, West Virginia, and Wyoming. The tree is usually found in old fields and other open areas, and in woodlands. It prefers moist to dry sandy and rocky soils. Heartwood Color Yellow to golden-yellow to orange Brown Greenish to greyish Dark brown Reddish brown The heartwood varies from greenish-yellow to dark or golden brown, somtimes with a shade of green. It turns to a russet shade upon exposure. Sapwood Color Red Pink White to yellow Well defined Yellowish Paler than heartwood Narrow Grain Straight Figure Growth rings (figure) Stripe (figure) Distinct (figure) Even Straight Clear growth rings (figure) Striped figure Distinct figure The grain is usually straight, and is described as prominent. Texture Fine Even or uniform Coarse Medium to coarse Uneven Somewhat coarse Luster Lustrous Pronounced Natural Durability Perishable Durable Very durable Susceptible to attack from powder post (Lyctid & Bostrychid) beetles Sapwood not resistant to decay Resistant to wood staining fungal attack Resistant to attack from termites (Isoptera) Moderately resistant to termite (Isoptera) attack Heartwood resistant to decay Good weathering properties, well suited for exterior applications. Good resistance to the adverse effects of weather Standing trees are vulnerable to a boring insect which destroys the wood or makes it less suitable for shade Odor Has an odor No specific smell or taste Light-Induced Color Change Darker Toxicity Poisonous Kiln Schedules Dry at a slow speed UK=A US=T2D4/T2D3 Fr=1 US=T6A3/T3A1 UK=A Drying Defects Checking Distortion Severe twisting/warping Moderate twist/warp Severe end splitting Refractory wood may cause end and surface checks during drying Ease of Drying Medium to High Shrinkage Reconditioning Treatement Rapidly Little degrade Easy High tendency to distort in reponse to changes in moisture content Dries slowly Tree Identification Bole/stem form is misshapen Bole/stem form is fluted Bole/stem form is straight Tree Size It is a fast growing species. Spiny tree Product Sources Supplies of Black locust are readily available in the eastern United States, and is usually priced in the moderate range. Substitutes Courbaril (Hymanaea courbaril) Comments General finishing qualities are rated as good Blunting Effect Moderate Moderate dulling effect on cutting edges Blunting effect on machining is moderate Boring Fair to good results Fairly easy to very easy Carving Fair to Good Results Fairly Easy to Very Easy Cutting Resistance Cutting resistance with dry wood is moderate The soft earlywood is more difficult to cut than the hard latewood Gluing Fair to Good Results Fairly Easy to Very Easy Easy to glue Good properties Mortising Fair to Good Results Fairly Easy to Very Easy Moulding Fair to Good Results Fairly Easy to Very Easy Movement in Service Stable Nailing Fair to Good Results Fairly Easy to Very Easy Difficult to nail Possible if prebored Holds nails well Planing Fair to Good Results Fairly Easy to Very Easy Responds very well to machining Planes to a smooth surface Resistance to Impregnation Heartwood is highly resistant Response to Hand Tools Easy to machine Moderate working qualities Difficult to machine Routing & Recessing Fair to Good Results Fairly Easy to Very Easy Screwing Fair to Good Results Fairly Easy to Very Easy Possible if prebored Poor screwing properties Turning Fair to Good Results Fairly Easy to Very Easy Good results Easy to turn Veneering Qualities There is slight to moderate drying degrade and the potential for buckles and splits Moderately easy to veneer Steam Bending Very good It bends equally well in either the green or air-dried state. Polishing Satisfactory results Good results High finish Staining Fair to Good Results Fairly Easy to Very Easy Finish is generally satisfactory Satisfactory properties Strength Properties Density (dry weight) = 46-52 lbs/cu. ft. Shearing strength (parallel to grain) = medium Shearing strength (parallel to grain) = low Modulus of Elasticity (stiffness) = medium Max. crushing strength = medium Max. crushing strength = high Hardness (side grain) = medium Density (dry weight) = 38-45 lbs/cu. ft. Bending strength (MOR) = medium Bending strength (MOR) = high Toughness-Hammer drop (Impact strength) = high Max. crushing strength = low Hardness (side grain) = soft Weight = very high Shrinkage, Tangential = moderate Shrinkage, Radial = moderate Shearing strength (parallel to grain) = high Modulus of Elasticity (stiffness) = low Max. crushing strength = very high Hardness = medium Density (dry weight) = 31-37 lbs/cu. ft. Compression strength (parallel to grain) = very high Bending strength (MOR) = very high Air-Dried condition about 12% moisture content Black locust is stronger and stiffer than White oak, and its bending properties are comparable to those of Ash and Beech. The tree is widely planted as an ornamental and for shelterbelts. It is also used for erosion control, especially on strip-mined areas, because of its spreading roots system. Numerical Data Item Green Dry English Bending Strength 12738 18761 psi Crushing Strength 1137 1793 psi Density 44 lbs/ft3 Hardness 1560 lbs Impact Strength 43 56 inches Maximum Crushing Strength 6159 9259 psi Shearing Strength 2282 psi Stiffness 1735 1961 1000 psi Work to Maximum Load 12 15 inch-lbs/in3 Specific Gravity 0.65 0.65 Weight 46 45 lbs/ft3 Radial Shrinkage 4 % Tangential Shrinkage 7 % Volumetric Shrinkage 10 % Item Green Dry Metric Bending Strength 895 1319 kg/cm2 Crushing Strength 79 126 kg/cm2 Density 705 kg/m3 Hardness 707 kg Impact Strength 109 142 cm Maximum Crushing Strength 433 650 kg/cm2 Shearing Strength 160 kg/cm2 Stiffness 121 137 1000 kg/cm2 Work to Maximum Load 0.84 1.05 cm-kg/cm3 Specific Gravity 0.65 0.65 Weight 737 721 kg/m3 Radial Shrinkage 4 % Tangential Shrinkage 7 % 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. 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. 6 Europe,TRADA, Red Booklet Series Clifford, N.,1953,Commercial Hardwoods - Their Characteristics Identification and,Utilization,Sir Isaac Pitman & Sons Ltd. London Clifford, N.,1957,Timber Identification for the Builder and Architect,Leonard Hill (Books) LTD. London Dave Faison. Into the Woods. Personal Communication, 1993. Farmer, R.H.,1972,Handbook of Hardwoods,HMSO Forest Products Research Laboratory, U.K.,1967,The Steam Bending Properties of various timbers,Forest Products Research Laboratory, Princes Risborough, Leaflet,No.45 HMSO, 1981. Handbook of Hardwoods, 2nd Edition. Revised by R.H. Farmer. Department of the Environment, Building Research Establishment, Princes Risborough Laboratory, Princes Risborough, Aylesbury, Buckinghamshire 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 Kline, M. 1983. Robinia pseudoacacia - Black locust. In A Guide to Useful Woods of the World. Flynn Jr., J.H., Editor. King Philip Publishing Co., Portland, Maine. 1994. Page 318. Kloot, N.H., Bolza, E.,1961,Properties of Timbers Imported into Australia,C.S.I.R.O. Forest Products Division Technological Paper,No.12 Laidlaw, W.B.R. 1960. Guide to British Hardwoods. Published by Leonard Hill [Books] Limited, 9 Eden Street, N.W.1, London. Little, E.L. 1980. The Audobon Society Field Guide to North American Trees - Western 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 McAlister, R.H.,1971,American Woods - Black locust,USDA, Forest Service American Woods FS-224 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 Rendle, B.J.,1969,World Timbers (3 Vols.,Ernest Benn Ltd. London Smith, D.N.,1959,The Natural Durability of Timber,Forest Products Research Laboratory, Princes Risborough, Building Research,Establishment Record,No.30 Stone, H.,1924,The Timbers of Commerce and their Identification,William Rider & Sons Ltd. London T.R.A.D.A.,1942,Home-grown timber trees - their characteristics, cultivation and Uses,TRADA Timber Development Association Ltd.,1955,World Timbers (3 Vols.,Timber Development Association Ltd. 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. Agriculture Handbook No. 72. United States Department of Agriculture, Forest Service, 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