CONTRIBUTORS - WOOD WORKS
WEEPING WILLOW: HARD FACTS
Botanical / scientific name: Salix babylonica
(Family: Salicaceae)
Trade name: Weeping willow (South Africa)
Other names: babylon willow, treurwilger
Origin: China
Conservation status: The species is not included in the IUCN Red List of Threatened Species.
Bole characteristics: Weeping willow is a medium-sized to large tree, reaching an average height of 11m in
South Africa (the highest recorded tree in South Africa is 20m). In its natural habitat, it
grows to 20 to 25m in height.
Colour: The heartwood is light pinkish to brownish and the sapwood is white.
Grain pattern: The wood has a fine texture and a straight grain.
Density: The air-dry density ranges from 460 to 540kg/m 3 with the average about 510kg/m 3 .
Strength / bending properties: The wood is light and soft with very low to low strength properties.
Seasoning: Air-drying – slow drying under cover is recommended.
Durability and preservative
treatment: Kiln drying schedule 3 is recommended (see below).
Working and finishing
properties: The wood is perishable and moderately resistant to preservative treatment.
TIMBER DRYING SCHEDULE FOR WEEPING WILLOW (Salix babylonica)
Supplied by H-P Stöhr, Timber Drying Institute ([email protected])
Dry Bulb temperatures (°C) and Relative Humidity (%) at the following Timber Moisture Contents
Drying schedule no.
3
Green
40%
30%
18% to final
DB RH% DB RH% DB RH% DB RH%
50 71 55 64 60 53 70 36
DB = Dry bulb temperature, RH = Relative Humidity
Please note: Drying schedules only serve as a guide to the kiln operator, with the response
of the timber to the drying condition being the criterion.
REFERENCES AND SOURCES
1. Flynn, JH and Holder, CD (ed.) 2001. A Guide to Useful Woods of the World. Forest Products Society, Madison, WI
2. Glen, H and van Wyk, B. 2016. Guide to Trees Introduced into Southern Africa. Struik Nature, Cape Town
3. Otto, KP and van Vuuren, WFJ. 1977. The Mechanical Properties of Timbers with Particular Reference to Those Grown in
the Republic of South Africa. Bulletin 48. Department of Forestry, Pretoria
4. Pakenham, T. 2007. Meetings with Remarkable Trees. Jonathan Ball Publishers, Cape Town
5. Petherick, T. 2006. Trees That Shape the World. Quadrille Publishing Limited, London
6. Poynton, RJ. 1984. Characteristics and Uses of Selected Trees and Shrubs Cultivated in South Africa. Bulletin 39. South
African Forestry Research Institute, Directorate of Forestry, Pretoria
7. Prospect Database. 1997-2004. Oxford Forestry Institute, Department of Plant Sciences, University of Oxford
8. Van Vuuren NJJ, Banks CH and Stöhr H-P. 1978. Shrinkage and Density of Timbers Used in the Republic of South Africa
9. Bulletin 57. Department of Forestry, Pretoria
10. https://en.wikipaedia.org/wiki/Salix_babylonica
11. Von Breitenbach, F. 1989. National List of Introduced Trees. Dendrological Foundation, Pretoria
12. Wiselius, SI. 2005. Hout Vademecum, Sdu Publishers, The Hague, Netherlands
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