Some factors governing mycelial establishment and lesion extension in the larch canker disease

From inoculations on larch trees with mycelium of Trichoscyphella willkommii it was shown that seasonal variation in lesion development was the result of varying ability by the host to limit mycelial spread. Freezing conditions as well as fungal infection were shown to be essential for canker extension and the mechanism was apparently an alternation of the two factors during the winter.