I understand the lifecycle in basic terms only I'm sorry.
Sapwood exposed colonisation strategy spread at night by airborne spores. Enters through cracks, splits that expose the sapwood. Probably endophytic (lives in host without causing disease or issue).
Prefers to colonise dead / decaying tissue. (Saporophytic). Does not have wherewithal to attack barriers protecting living wood.
Needs moisture to germinate, fungal body acts as a source of this moisture.
If you wanted any more detail I would have to talk to my colleague at work who is a mycologist... He appears to speak a different language for the most part though!
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