Driftwood Q's?

You don't want the wood to rot quickly so anything that's soft is mushy is not good. You basically want the "core" of the wood, it's hardest part so it lasts the longest I think. You don't want the stuff decomposing and making a mess in your tank. I've heard you want to scrap off all bark for this reason.
 
I've not had this problem with any that I've collected, but have had some that spent a few years in my aquarium get soft. I think it is just in a more advanced state of decomposition, but can't say for sure, Hopefully someone with a deeper knowledge will weigh in here as well, but I generally don't worry unless it seems to want to break up after being soaked.
 
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