Scientific Name
Salix fragilis
Trade Name
Crack Willow
Family Name
Salicaceae
Common Names
Crack willow, Sauce, Skorpil, Willow
Regions of Distribution
Eastern Europe, Oceania and S.E. Asia, Western Europe
Countries of Distribution [VIEW MAP]
Switzerland, United Kingdom
Common Uses
Artificial limbs
Baskets
Boxes and crates
Charcoal
Cooperages
Decorative veneer
Flooring
Flooring: industrial heavy traffic
Interior trim
Marquetry
Paneling
Plywood
Toys
Environmental Profile
| Rather secure within its natural growth range | ||||||||||||
| Data source is World Conservation Monitoring Center | ||||||||||||
| Abundant |
Distribution Overview
Crack willow is native to Europe and western Asia, but has naturalized in North America, from Newfoundland to Virginia, west to Kansas, and north to North Dakota. It is usually found on roadsides, along streams and in clearings. It prefers moist soils.
Heartwood Color
| Yellow | ||||||||||||
| White | ||||||||||||
| Orange | ||||||||||||
| Pale red to pink | ||||||||||||
| White to cream | ||||||||||||
| White pinkish |
Sapwood Color
| White to yellow | ||||||||||||
| Whitish |
Grain
| Straight | ||||||||||||
| Even |
| Straight |
Texture
| Coarse | ||||||||||||
| Medium | ||||||||||||
| Fine | ||||||||||||
| Even textured |
Natural Durability
| Perishable | ||||||||||||
| Non-durable | ||||||||||||
| Perishable | ||||||||||||
| Non durable |
The heartwood is non-durable and is susceptible to attack by insects. The sapwood is vulnerable to attack by the powder-post and common furniture beetles. Trees and logs are vulnerable to attack by forest longhorn or Buprestid beetle.
Odor
| No specific smell or taste |
Kiln Schedules
| Drying (speed) is fast | ||||||||||||
| UK=H US=T10D4S/T8D3S Fr=7 | ||||||||||||
| UK=H | ||||||||||||
| UK=F US=T6D4/T3D3 Fr=6 |
Drying Defects
| Distortion | ||||||||||||
| Water pockets |
Ease of Drying
| Slowly | ||||||||||||
| Rapidly | ||||||||||||
| Easy | ||||||||||||
| Moisture content should be monitored to insure uniformity | ||||||||||||
| Dries fairly quickly with minimum degrade | ||||||||||||
| Dries at a fairly rapid rate |
Kiln Drying Rate
| Naturally dries slowly | ||||||||||||
| Naturally dries quickly |
Tree Size
| Tree height is 30-40 m |
Comments
General finishing qualities are rated as good
Blunting Effect
| Little | ||||||||||||
| Slight bluting effect on cutting tools | ||||||||||||
| Blunting effect on machining is slight |
Boring
| Easy, especially when cutters are kept very sharp |
Carving
| The operation requires sharp cutting edges for best results | ||||||||||||
| Good results |
Cutting Resistance
| Easy to saw | ||||||||||||
| May split severly | ||||||||||||
| Low resistance |
Gluing
| Easy to glue | ||||||||||||
| Excellent gluing properties |
Mortising
To prevent rough surfaces, sharp cutting edges are required in most machining operations, including mortising
Moulding
The timber responds well to ordinary tools with sharp cutting edges in moulding operations, with very good results
Movement in Service
| Retains its shape well after manufacture | ||||||||||||
| Dimensionally stable |
Nailing
| Good nailing properties |
Planing
| Poor to Very Poor Results | ||||||||||||
| Requires sharp cutting edges to prevent fuzzy surfaces | ||||||||||||
| Reduced cutting angles recommended | ||||||||||||
| Planes and works well with ordinary machine tools |
Resistance to Impregnation
| Permeable heartwood | ||||||||||||
| Permeable sapwood | ||||||||||||
| Sapwood is permeable | ||||||||||||
| Heartwood is resistant | ||||||||||||
| Heartwood is highly resistant | ||||||||||||
| Sapwood is treatable |
Response to Hand Tools
| Easy to Work | ||||||||||||
| Easy to machine |
Response to hand tools, with sharp cutting edges, is very good.
Routing & Recessing
The material responds readily to sharp cutting edges to yield good results in routing operations
Sanding
| Good characteristics |
Screwing
| Good screwing properties |
Turning
| Sharp cutting edges necessary to prevent woolly surfaces | ||||||||||||
| Easy to turn |
Steam Bending
| Poor |
Polishing
| Satisfactory results | ||||||||||||
| High finish |
Staining
| Finish is generally satisfactory |
Strength Properties
| Max. crushing strength = low | ||||||||||||
| Modulus of Elasticity (stiffness) = very low | ||||||||||||
| Bending strength (MOR) = low | ||||||||||||
| Density (dry weight) = 23-30 lbs/cu. ft. | ||||||||||||
| Shearing strength (parallel to grain) = very low | ||||||||||||
| Toughness (total work) = medium | ||||||||||||
| Max. crushing strength (stiffness) = very low | ||||||||||||
| Weight = medium | ||||||||||||
| Toughness-Hammer drop (Impact Strength) = medium | ||||||||||||
| Toughness-Hammer drop (Impact Strength) = low | ||||||||||||
| Toughness (total work) = low | ||||||||||||
| Surfaces may dent or scratch easily | ||||||||||||
| Not hard | ||||||||||||
| Density = medium | ||||||||||||
| Compression strength (parallel to grain) = low | ||||||||||||
| Bending strength (MOR) = medium | ||||||||||||
| Air-Dried condition about 12% moisture content |
Numerical Data
| Item | Green | Dry | English |
| Bending Strength | 5540 | 9405 | psi |
| Density | 27 | lbs/ft3 | |
| Hardness | 637 | lbs | |
| Impact Strength | 33 | 32 | inches |
| Maximum Crushing Strength | 1882 | 3534 | psi |
| Shearing Strength | 982 | psi | |
| Stiffness | 952 | 1152 | 1000 psi |
| Toughness | 222 | inch-lbs | |
| Work to Maximum Load | 8 | 12 | inch-lbs/in3 |
| Specific Gravity | 0.34 | 0.38 | |
| Weight | 26 | 25 | lbs/ft3 |
| Item | Green | Dry | Metric |
| Bending Strength | 389 | 661 | kg/cm2 |
| Density | 432 | kg/m3 | |
| Hardness | 288 | kg | |
| Impact Strength | 83 | 81 | cm |
| Maximum Crushing Strength | 132 | 248 | kg/cm2 |
| Shearing Strength | 69 | kg/cm2 | |
| Stiffness | 66 | 80 | 1000 kg/cm2 |
| Toughness | 255 | cm-kg | |
| Work to Maximum Load | 0.56 | 0.84 | cm-kg/cm3 |
| Specific Gravity | 0.34 | 0.38 |
References
Armstrong, F.H.,1960,The Strength Properties of Timber,Forest Products Research Laboratory, London Bulletin,No.45
Farmer, R.H.,1972,Handbook of Hardwoods,HMSO
Forest Products Research Laboratory, U.K.,1937,A Handbook of Home-Grown Timbers,HMSO
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.
Laidlaw, W.B.R. 1960. Guide to British Hardwoods. Published by Leonard Hill [Books] Limited, 9 Eden Street, N.W.1, London.
Lavers, G.M. 1966. The Strength Properties of Timbers. Forest Products Research Bulletin, No. 50. Ministry of Technology, Her Majesty’s Stationery Office, London.
Lavers, G.M.,1983,The Strength Properties of Timber (3rd ed. revised Moore G.L.,Forest Products Research Laboratory, Princes Risborough, Building Research,Establishment Report (formerly Bulletin No.50)
Lincoln, W.A. 1986. World Woods in Color. Linden Publishing Co. Inc., Fresno, California.
Little, E.L. 1980. The Audubon Society Field Guide to North American Trees – Eastern Region. Published by Arthur A. Knopf, New York.
Redding, L.W.,1971,Resistance of Timbers to Impregnation with Creosote,Forest Products Research Laboratory, Princes Risborough, Building Research,Establishment Bulletin No.54 pp.43
Smith, D.N.,1959,The Natural Durability of Timber,Forest Products Research Laboratory, Princes Risborough, Building Research,Establishment Record,No.30
T.D.A.,1942,Timber Leaflet – No.67 Willow,TRADA Timber Leaflet
WCMC. 1992. Conservation Status Listing: Trees and Timbers of the World. World Conservation Monitoring Center (WCMC, Plants Program, 219 Huntingdon Road, Cambridge, CB3 ODL, United Kingdom.