| dc.description.abstract | Wood used in outside applications is susceptible to weathering and photo degradation, which often leads to surface discoloration, loss of brightness and surface deterioration. Research has shown that acetylated wood is more resistant against brown rot, white rot and soft rot, and more dimensionally stable than untreated wood. However, acetylated wood seems still to be disfigured by surface moulds and staining fungi. Samples of acetylated Southern Yellow pine at three different treatment levels; low, intermediate and high acetyl content were exposed at two test sites, Ås (Norway) and Bogesund (Sweden) against north and south from September 2010 until March/May 2011. Considerably more precipitation was recorded in Ås in the initial potential fungal growth phase than in Bogesund. As expected, untreated wood had higher mould ratings than acetylated wood. At Ås the tendency was that samples with low acetyl content had lower mould ratings than samples with higher acetyl content. This effect was not found in Bogesund. This may be due to considerably less precipitation in Bogesund compared to Ås. At Ås samples exposed against north tended to have higher mould ratings than panels exposed against south which could be due by less direct sun causing longer time of wetness and more ideal conditions for mould growth. | |
