Transnational Accesses

Technical Information

SilviScan – efficient instrument for detailed characterization of wood and fibre properties

SilviScan is a measurement system built to provide efficient characterisation of variations in a large number of important properties of wood. The measurements are performed on sample strips of wood, from pith to bark or parts of interest, produced from discs, increment cores, battens from mechanical testing or other sources with high precision equipment in the laboratory. The sample strips are mounted on computer controlled motorised stages and are automatically scanned for information on property variations along their full lengths. Characterisation is performed on 1 to 3 separate units representing different measurement methods, depending on what properties are of interest:

  • Cell Scanner with a video microscope for information of numbers and sizes of fibres and vessels, as well as orientations of annual rings. As an option, a probe can be mounted for collection of NIR spectra.
  • Density Scanner recording X-ray absorption images for information about wood density variations.
  • Diffraction Scanner recording X-ray diffraction images for information about orientations of microfibrils, etc. in the wood matrix.

The SilviScan includes three separate units representing different measurement principles. The sample strips are mounted on motorized stages for scanning of the samples all along their length. The measurements on and data from the different units are integrated via a server, which makes possible the analysis of wide spectrum of properties of wood and fibres, as well as of annual rings and parts thereof, and for hardwoods also of vessels. Image: Robert Evans, CSIRO.

  • As an option, a probe can be mounted for collection of series of consecutive NIR spectra along the full length of the sample.

The NIR Wood Scanner adapted to the SilviScan, with a wood sample strip mounted on the motorized stage ready to pass the probe for scanning (left), and a resulting sequence of NIR spectra recorded from consecutive intervals from pith to bark. Image: Innventia.

The units are integrated via a server that also compiles all images and data for further analyses. Routines have been developed to prepare data for dedicated evaluations related to different research fields.

Examples of application

1. Development of genetic markers for important traits/Bio4Energy and the Swedish Conifer Initiative

Innventia is using the SilviScan instrument as part of its engagement in the strategic research area Bio4Energy funded by the Swedish government in cooperation with Umeå University (UmU), the Swedish University of Agricultural Sciences (SLU) and Luleå University of Technology (LTU). Within its platform "Feedstock", Innventia is analysing growth and properties of 6000 Norway spruce (Picea abies) trees and organising the Bio4Energy Trait Database, to include all trait information of different natures collected from these trees within the project. These data will be used in association mapping to develop genetic markers for important traits.
(Ongoing project, see Bio4Energy project web-site, references not yet available).

2. Properties of wood, genetics and effects on products

Properties like wood density, microfibril angle and fibre angle and their variations within stems may have crucial effects on the suitability of wood for sawn products in relation to stiffness, deformations on drying, etc. SilviScan has been used to investigate differences among species and progeny and determine genetic parameters, as well as in investigations of effects on industrial products. Examples are work with Forest Research (UK) on Sitka spruce (Picea sitchensis), SLU (Sweden) on Scots pine (Pinus sylvestris), and the Norwegian Forest and Landscape Institute on genetic and environmental variation and correlation patterns for mechanical properties in Norway spruce.

  • Steffenrem, A., Saranpää, P., Lundqvist, S.-O., Skrøppa, T. 2007: Variation of wood properties among five full-sib families of Norway spruce (Picea abies). Ann. For. Sci. 64, 799-806. doi:10.1051/forest:2007062

3. Benchmarking of tree species; Optimization of use; Properties of drought resistant species in South Africa

Innventia has developed protocols for mapping of differences in properties (trees, wood and fibres, pulps and sheets) of materials originating from different tree species and clones, growth conditions, and parts of trees. Most of the properties involved are measured with SilviScan. A Benchmarking Database has been built. Such data encompassing the chain from within tree variations to sheet properties have now been compiled for 13 softwood and hardwood species and hybrid crossings from three continents. It is used to compare materials, develop models for property variations, to establish effects of tree/wood/fibre properties on products and to find optimal uses of existing resources and select species/clones for plantations from industrial perspectives. The approach is now applied by Innventia in South Africa on three drought resistant types of eucalypts (Eucalyptus spp.) to find suitable trees to plant in arid areas for development of the rural society and alleviation of poverty.
(Ongoing project, references not yet available).

4. Effects of climate change

SilviScan was used to provide data for a project of Metla (Finland) and SLU (Sweden), in which stem wood properties of mature Norway spruce after 3 years of continuous exposure to elevated [CO2] and temperature were investigated. Trees in whole-tree chambers were exposed to different environments. Samples from the trees were investigated with SilviScan, providing information about average properties of wood and fibres in growth rings formed different years, providing a basis for evaluations of expected effects from climate change.

  • Kostiainen, K., Kaakinen, S., Saranpää, P., Sigurdsson, B.D., Lundqvist, S.-O., Linder, S. & Vapaavuori, E. 2009. Stem wood properties of mature Norway spruce after three years of continuous exposure to elevated [CO2] and temperature. Global Change Biology 15, 368-379. doi:10.1111/j.1365-2486.2008.01755.x

5. Models for properties variations in trees; Forest Resource Databases

The SilviScan instrument and other instruments at Innventia have been used to analyse radial variations in wood and fibre properties from samples taken at different positions along stems of trees from stands of different ages and growth conditions. From such data, models describing property variations within and between stems, ages, growth conditions and species have been developed. The models have been used to compare raw materials from different origins (species, regions and ages, thinning versus final cut operations, logs versus sawmill chips, etc.). The concept of Forest Resource Databases has been developed: Data from forest inventorying are used as input data to an integrated set of models to simulate properties and volumes of trees representing regional or national resources, as well as of materials possible to harvest from these trees (logs, chips, ...), providing a good overall picture of the available resource and a basis for optimisation of the wood use.

  • Lundqvist S.-O., Grahn T., Hedenberg Ö. 2005. Models for fibre dimensions in different softwood species. Simulation and comparison of within and between tree variations for Norway and Sitka spruce, Scots and Loblolly pine. Proceedings of Fifth IUFRO Workshop on "Connection between Forest Resources and Wood Quality: Modelling Approaches and Simulation Software, Waiheke Island Resort, Auckland, New Zealand, November 20-27, 2005. Also published as STFI-Packforsk Report ART 05/54
  • Franceschini Tony, Lundqvist Sven-Olof, Bontemps Jean-Daniel, Grahn Thomas, Olsson Lars, Evans Robert, Leban Jean-Michel. 2012. Empirical models for radial and tangential fibre width in tree rings of Norway spruce in north-western Europe. Holzforschung  01/2012. doi:10.1515/HF.2011.150
  • Lundqvist S.-O., Grahn T. 2008. Forest Resource Databases - a concept for product-oriented mapping of properties and volumes in forest resource. STFI-Packforsk Report no 446, October 2008