A high-throughput X-ray-based method for measurements of relative wood density from unprepared increment cores from Picea abies

Abstract

We have described a high-throughput method for ring width and relative wood density analysis of unprepared increment cores based on conventional computer tomography scanners (CT scanners) used in health care. The method was developed for analysis of 5-mm increment cores collected in forest genetic and tree breeding trials. For these studies, the relative differences between individuals are more important than the exact value. The method is highly efficient in terms of quantitative data collection from large number of samples. There are, however, limitations in terms of resolution and accuracy on very small volumes of wood that must be considered when using the method to measure individual growth rings or increment cores thinner than 5 mm. However, in studies comprising large number of samples, the use of cost-efficient CT scanning on the major part of the material, combined with more laborious high-resolution scanning on sub-samples can be a good combination for efficient determination of radial variation in growth rate and wood density.

Keywords:

• X-ray scanning
• computer tomograph
• wood science
• increment cores
• wood density
• growth rings

Acknowledgements

Sven-Olof Lundqvist at Innventia, Stockholm, for discussions and comments on the manuscript and providing the data from SilviScan^®-3; Geir Østreng, Siri Bjoner and Aaron Smith at the Norwegian forest and landscape institute for coordination of the collection and preparation of the samples and highly appreciated discussions on the methodology; and an anonymous reviewers valuable corrections and discussion.

Funding

The method was developed as a part of the projects: WoodWisdom-Net programme (2008–2011) [grant number 522006A] and Norwegian Research Council (NRC) [grant number 184665/I10] “Wood formation under varying environmental conditions (WOVEN)” coordinated by Harri Mäkinen (Finnish Forest Research institute); NRC [grant number 199346/I10] “Breeding Norway spruce for beneficial wood properties and resistance against root rot and bark beetle associated blue-stain fungi attacks (WoodRes)” coordinated by Tore Skrøppa and financed by NRC and the Norwegian Forest Seed Center.

Additional information

Funding

Funding: The method was developed as a part of the projects: WoodWisdom-Net programme (2008–2011) [grant number 522006A] and Norwegian Research Council (NRC) [grant number 184665/I10] “Wood formation under varying environmental conditions (WOVEN)” coordinated by Harri Mäkinen (Finnish Forest Research institute); NRC [grant number 199346/I10] “Breeding Norway spruce for beneficial wood properties and resistance against root rot and bark beetle associated blue-stain fungi attacks (WoodRes)” coordinated by Tore Skrøppa and financed by NRC and the Norwegian Forest Seed Center.