FUNGI IN BARK PEELING WOUNDS OF PICEA-ABIES IN CENTRAL SWEDEN

A total of 210 Norway spruce trees with stem wounds resulting from bar k peeling by moose (Alces ales) were examined in three 45-50-year-old stands that contained 20-30% of damaged trees. Injured stems were betw een 8 and 40 cm diameter at breast height (d.b.h.) and showed 1 to 23- year-old wounds. Wounds varied in size from 2 to 4815 cm(2). The size of injury correlated negatively with the age of the injury (r = -0.24; p = 0.004), and positive correlation was established between the age of the injury and d.b.h. of the wounded tree (r = 0.50; p = 0.0001). E ach wound was sampled once using an increment borer and fungi were iso lated. Among basidiomycetes, Stereum sanguinolentum was the most commo n (isolated from 26.7% of the damaged stems). Other common species wer e Cylindrobasidium evolvens (23.8%), Amylostereum areolatum (5.2%), A. chailletu (0.5%), Heterobasidion annosum (5.2%), Peniophora pithya (1 .4%), Sistotrema brinkmannii (1.0%). The ascomycete Nectria fuckeliana was the most common among all fungi (present in 35.7% of bark peeling wounds). The frequency of S. sanguino-letum infection correlated posi tively with the age of the injury (r = 0.27; p = 0.001) and the opposi te relationship was revealed for c. evolvens (r = -0.30; p = 0.0001). Furthermore, C. envolvens infection correlated positively with the wou nd size (r = 0.30; p = 0.0001) and negatively with the tree d.b.h. (r = -0.20; p = 0.004). A positive correlation was found between tree d.b .h. and the occurrence in stems of H. annosum (r = 0.23; p = 0.001) an d N. fuckeliana (r = 0.23; p = 0.0006). The spruce bark beetle Dendroc tonus micans attacked 14.8% of wounded trees. Presence in stems of N. fuckelina was associated significantly with the D. micans attack (r = 0.190; p = 0.006; chi(2) test: P = 0.01) Except for a negative correla tion between infections of S. sanguinolentum and H. annosum (r = -0.14 0; p = 0.04), no significant relationship between fungal species was f ound.