I knew soil type was a big factor - we have concentrations of peat nearby, but fortunately no open bogs - sadly I can no longer hike the nature preserves here that have open bogs, nor do I use it in my gardens and pots. But I never thought about the effect of the humidity putting the NTM directly into the air! Maybe that explains some of the geographic differences in infection.

We learn so much here from each other.
Sue