The spreading of the S type of Heterobasidion annosum from Norway spruce stumps to the subsequent tree stand

摘要: Summary The occurrence of Heterobasidion annosum in stumps and growing trees was investigated on 15 forest sites southern Finland where the previous tree stand had been Norway spruce (Picea abies) infected by H. annosum, present either Scots pine (Pinus sylvestris), lodgepole contorta), Siberian larch (Larix siberica), silver birch (Betula pendula) or 8–53 years old. Out 712 stand, 26.3% were S group 0.3% P annosum. The fungus alive fruit bodies active even cut 46 ago. In subsequent proportion with root rot increased stands decreased other species. On average, one type genet spreading from an old stump 3.0 following 0.5 pine, 0.3 larch, 0.05 0.03 stand. Although generally highly resistant to found site that planted a very northern provenance.