Spread of Amylostereum areolatum and A-chailletii decay in living stems ofPicea abies

Fifteen injured Picea abies stems infected with Amylostereum areolatum and 14 stems with A. chailletii were cut and dissected. There were no significa nt differences between the spread of A. areolatum and that of A. chailletii within the stems. During the first 10 years after injury, average vertical spread for both species was 2.8 m, and spread over stem cross section cons tituted approximately 130-160 cm(2), thus affecting 30-40 per cent of the t otal cross section area. Tunnels made by woodwasp larvae were encountered i n every analysed stem, and in all cases they were situated within the colum ns of decayed wood. Correlation analyses showed positive relationships betw een wound size and length of decay, between tree diameter at breast height (d.b.h.) and spread of decay over stem cross section, between tree d.b.h. a nd length of decay, and between width of annual growth rings and decay cros s section area.