Use lesser known species - New report lists alternatives to Greenheart and Ekki
Tropical forests hold a multitude of lesser-known wood species. A great number of these are potentially valuable timber species i.e. have an unfulfilled sustainable production potential. Buyers have a tendency to specify well-known species and request specific species for historical and traditional reasons which puts a lot of pressure on those species and threatens the long term supply.
The UK Government’s Timber Procurement Advice Note requires that ‘fit-for-purpose’ is specified in the bid rather than specifying certain species. This provides the timber supplier with some room for manoeuver in the quest to find well-managed forests for their sources of timber. If the tropical timber meets the policy requirements and is from a sustainable or FLEGT licensed source it is perfectly fine to specify and use.
Poor knowledge of the physical wood properties and possible end-uses of the lesser-known species are often mentioned as reasons why the species has not yet been incorporated onto the international market. However, poor distribution of the existing knowledge on the species to manufacturers and wood buyers seem to be one of the most limiting factors for the usage of lesser-known species.
Guidance from the Environment Agency lists alternatives to Greenheart and Ekki
Traditionally, for use in marine and freshwater construction in the UK, there has been, and still is, a heavy reliance on just two species; Greenheart (Chlorocardium rodiei) and Ekki (Azobe,Lophira alata). A guide to help the specification and use of lesser-known species of hardwood timber in marine and freshwater construction applications, as alternatives to Greenheart and Ekki, was published earlier this year. The guide is based on a research project commissioned by the Environment Agency and will be of interest to anyone who uses timber in marine and freshwater applications, particularly structural and civil engineers, design consultants, building contractors and asset managers. It contains a step-by-step methodology to identify the most suitable timbers for use in different applications, together with a table containing technical data on the key properties (e.g. strength, marine borer and abrasion resistance) of five lesser-known species which have been benchmarked against the performance of Greenheart and Ekki. The five species are Angelim Vermelho (Dinizia excelsa Ducke), Cupiuba (Goupia glabra Aubl), Eveuss Klainidoxa gabonensis), Okan (Cylicodiscus gabunensis Harms) and Tali (Erythrophleum micranthum).
‘We hope that the report will trigger a step-change in the way that people evaluate and select the most suitable hardwood timbers for use in construction applications, and particularly that demand increases for the lesser known species that were tested as part of this research project’ says Melanie Meaden who led the project from the Environment Agency.
Newly identified timbers are already being used on Environment Agency coastal projects at Pevensey and Whitstable, and on a river project in Caversham.
The full research report, a project summary and the summarised guidance is available for download below.
Research Report/ Assessment of the durability and engineering properties of lesser-known hardwood timber species for use in marine and freshwater construction. Prepared by: TRADA Technology, Environment Agency and HR Wallingford/CETMEF (PDF 3.23 MB)
For further information see the Environment Agency’s website here.
Further information on lesser known species
A website which give an introduction to lesser-known species from the tropical regions of the world has also been developed by FSC Denmark. The site aims to collect and facilitate the existing knowledge on some of the most commercially relevant lesser-known species and lists a wide range of technical data and possible end-uses for several lesser-known species. See: http://www.fsc.dk/index.php?id=262