two questions, 1- why not just bleach it, dry, rinse and repeat? you probably wash filter parts with bleach don't you?
2- isn't this coming from cold water and you are moving it to tropical temps, different conditions?
I have 2 pieces of evergreen (pine or fir) wood that I pulled out of a lake and rinsed off, left it in the yard for a while and it froze. then I tossed it in my tank. I moved and brought the pieces to my new 210. damn stuff still floats after 3 years. I use a rock to hold one piece down and the other floats. all my pleco's chew the algae off and my water still get tannins after all this time. I think the worse part of the evergreen wood is the small pieces that came off and plug up my filter socks in my previous tank.
I'd do it again.