Previous studies in the UK have shown a marked difference in the susceptibility of logs of five softwood species to infection by sapstain fungi over a 4 month field trial. Recently this result has been confirmed and the rank order of greatest to least susceptibility in these commercially important species is lodgepole pine > Scots pine > Norway spruce > Japanese larch > Sitka spruce. Changes in moisture content and nutrient levels have also been assessed during the trial, as well as a study of differences in the resin composition of each wood species using GC-MS. Resin tapped from healthy, standing trees has been analysed and spectra derived from each species were compared. Resin formed at the edge of lesions on the outer sapwood surface, following inoculation of fresh billets with Sphaeropsis sapinea, has also been analysed. Factors influencing sapstain resistance are discussed.

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