European Journal of Wood and Wood Products

, Volume 77, Issue 6, pp 1137–1150 | Cite as

Surface mould growth on wood: a comparison of laboratory screening tests and outdoor performance

  • Solrun Karlsen LieEmail author
  • Geir I. Vestøl
  • Olav Høibø
  • Lone Ross Gobakken


Laboratory screening tests are commonly used to indicate wood materials’ resistance or susceptibility to surface mould growth, but the results can deviate from what happens during outdoor exposure. In this study, the aim was to investigate how well agar plate screening tests and water uptake tests can predict mould growth on exterior wooden claddings. The tested wood materials included Norway spruce heartwood (Picea abies), sapwood and heartwood of Scots pine (Pinus sylvestris), aspen (Populus tremula), acetylated Radiata pine (Pinus radiata) and DMDHEU-modified Scots pine sapwood. The agar plate test included four inoculation methods (two monoculture spore suspensions of Aureobasidium species, one mixed-culture spore suspension, and inoculation from outdoor air) and three incubation temperatures (5, 16 and 27 °C). Inoculation method and incubation temperature had significant effects on the mould rating in the agar plate screening test, but none of the agar plate test combinations gave good indications of outdoor performance. Results from the agar plate test gave significantly negative correlations or no significant correlation with results from the outdoor test. However, the water uptake test gave significantly positive correlations with outdoor mould rating, and could be a useful indicator of susceptibility of uncoated wooden claddings to surface mould growth.



The authors gratefully acknowledge Holger Militz and Kim Christian Krause (Georg-August-Universität Göttingen, Germany) for providing the DMDHEU material, Thor-Erik Vatne Alstad (Norwegian Institute of Bioeconomy Research) for assistance in the preparation of the specimens, Sigrun Kolstad (Norwegian Institute of Bioeconomy Research) for assistance during the water uptake test and the laboratory test, Ingrid Grønli (Mycoteam AS) for analysing the air samples and Cathrine Marie Whist (Mycoteam AS) for helping with fungal identification.


This study was funded by the Research Council of Norway through the WoodBeBetter project (Project no. 225345).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

107_2019_1444_MOESM1_ESM.pdf (1 mb)
Supplementary material 1 (PDF 1030 kb)


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Solrun Karlsen Lie
    • 1
    Email author
  • Geir I. Vestøl
    • 1
  • Olav Høibø
    • 1
  • Lone Ross Gobakken
    • 2
  1. 1.Faculty of Environmental Sciences and Natural Resource ManagementNorwegian University of Life SciencesÅsNorway
  2. 2.Norwegian Institute of Bioeconomy ResearchÅsNorway

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