Hardwoods in the United Kingdom Considerations When Looking to Future Planting and Future Value Chains

Reasons for increasing the diversity of the tree species providing wood for the value chain include: improving forest resilience to climate change; mitigating the risks of pests and pathogens; and improving other important functions of forests such as biodiversity, landscape protection and social benefits. This paper presents a summary of collated data on the broadleaves identified as having potential as future productive species in the United Kingdom, and that are currently being examined to create a shortlist for focusing resources on tree improvement work and silviculture. The data covers mechanical and physical properties, working qualities, natural durability, drying knowledge, and the potential for existing and emerging markets. Much of the data relating to UK-grown hardwoods is old, and not easy to find or interpret. The paper draws on information from the records of the former Forest Products Research Laboratory, as well as recent research data and industrial experience. The paper also summarises the work necessary to bring underutilised species into construction timber markets under the current standards framework. It outlines some of the knowledge that is missing in the current standards for hardwoods generally, and what needs to be done to make it easier for less mainstream hardwoods to be assigned structural design values. The aim of the paper is to inform researchers in countries facing similar challenges, in the hope that a more coordinated research strategy for wood value chain species diversification can emerge across Europe.