Compression Wood progress report - 1st June 2002 to 31st May 2003

Results and milestones

After 24 months the Compression Wood project has completed the majority of work in a number of areas:

  • Almost all fieldwork has been completed - measurements in one remaining Norway spruce stand will be completed by July 2003 and industrial trees in two Scots pine stands will be harvested in November 2003.
  • Classification systems for the identification of compression wood in discs have been drawn up and initial validation completed.
  • Protocols for field, disc exchange, laboratory and industrial measurements have been drawn up and agreed by partners.

Each partner has put the measurements from all the completed field sites into Access or Excel databases with standardised formats. The co-ordinator is now compiling all these databases into a central database, which will be completed early in the final reporting period. The vast majority of samples from the field sites have been prepared and measured and are in the process of being analysed.

A key outcome of the 2nd year has been agreement on the disc exchange protocol. All the intercomparison discs have been obtained, prepared and sent to the relevant partner for detailed examination. All partners involved in disc analysis have decided on their analysis system and completed initial validation. Over 5000 samples have already been classified and the remainder will be completed early in the next reporting period.

Detailed laboratory analysis has been undertaken of compression wood ultrastructure using the most up-to-date laboratory techniques such as:

Preliminary analysis has also been completed on the relationship between different mechanical properties and compression wood classification (PDF-528K). This has found that MOE tends to be lower in samples containing compression wood and that the relationship between density and MOE is weaker than in normal wood.

A large amount of industrial processing has been carried out. All sawlogs have been measured according to the agreed protocol. The majority of logs processed have been scanned either by 3-D scanners (PDF-563K) or CT scanning devices. These scanning techniques together with eigenfrequency measurements have been tested as methods for pre-sorting logs according to their compression wood content. Similar pre-sorting strategies have been undertaken with sawn timber by measuring their MOE using resonance vibration, stress wave and static bending. Distortion measurements have been made on sawn material following kiln drying and a number of different drying techniques studied to minimise the impact of compression wood. Post sawmill processing of wood containing compression wood has been conducted in planing trials and its use in window frames and re-engineered laminated timber evaluated.

Modelling work is progressing actively. Prototype models (PDF-220K) predicting the incidence and distribution of compression wood in relation to stem and log shape have been developed. Existing simulation models for predicting timber quality, growth and stand yield have been modified to reflect the impact of compression wood.

Benefits and beneficiaries

This project has enabled an extremely wide area of expertise and techniques to be brought to bear on the impact of compression wood on sawn timber in Europe. By working at all stages of the forest-wood chain from the impact of management to the use of sawn timber it will be possible to identify techniques and solutions for mitigating the impact of compression wood at the most appropriate stages of the whole process. It also enables people from each part of the forest-wood chain to gain a better understanding of the impact of compression wood at every stage of the industry.

A major component of the project is the active dissemination of knowledge to all parts of the industry. This is being undertaken in a number of ways including:

  • Making information and findings available on these web pages
  • Making presentations at industrial forums, scientific meetings, industry liaison groups
  • Publishing articles in trade and scientific journals.

A key element of the industrial liaison has been the dissemination and analysis of a questionnaire (PDF-142K) to industry in a number of the participating countries.

It is clear that the dissemination of information particularly following completion of the project will need to be carried out not only at the European scale but individually within the participating countries. Differences in the nature and structure of the forest and wood processing industries in each country, together with differences in comprehension of the impact of compression wood, will require different approaches to be adopted.

The main beneficiaries of the results and findings of the project will be the European softwood industry. Improvements in management and processing will be possible to minimise the impact of compression wood, to optimise utilisation and to improve financial return.

Future actions

The first part of the final reporting period will be involved in completing a number of outstanding tasks such as the completion of all field work and putting all basic stand and tree data into a centralised database. At the same time laboratory and industrial processing and testing will be completed and the results collated into centralised databases. A major effort will be made in the completion of the modelling element of the project. Such models allow different silvicultural and processing strategies to be tested and will help guide best practice.

Finally, the dissemination of information will take on heightened importance as different aspects of the project are concluded. A key outcome of the next year will be the drawing up of a Technology Implementation Plan detailing how the outcomes of the project will be communicated to the scientific community and the European forestry-wood chain.