>> some sort of beetle infestation in the past (for all I know, still did/does, as a woodpecker went after it earlier this year)
Ouch! Being perforated is not good for trees and other living things!
>> flood abatement work several years ago which (we hypothesize; we do not live near where that work was done) somehow resulted in a net lowering of the water level in *our* "creek"
Hmm! I imagine that everything in the soil and around it went through flux while adapting to that.
I would have thought that "trees" were the lowest-maintenance things one could have on a property. I guess not!
