Re: Regarding the use of treated plywood in boats...
I just cut up a Bayliner Capri 1600, I believe it was around a 1987 or so. There wasn't much wood left in that boat. If it was pressure treated, it didn't do it much good.
There was no floor left, the stingers had turned to mush and the transom was hollow. The total amount of wood or what was wood in that boat would have fit in a 5 gallon bucket. While I am sure it wasn't very well cared for over the years, it was by far the worst mess I'd ever seen. A tree is what did it in, but the glass and gel coat wasn't too bad other than the fact that a 40" tree trunk fell across the bow and windshield.
I was only able to salvage the trailer, and that needed a new bow stop and tongue.
The wood was actually slimy it was so rotted. The floors were like egg shells, the wood had rotted and fallen out from beneath the glass and gelcoat. It had sat for years after being shrink wrapped, the date on the shrink wrap was 1992, it was sitting under a lean to or carport, the tree brought that down on the boat too. The 40HP Force was also junk. It had sat since Jan. with the tree on it until I took it away. I have to say it was one of the easiest boats I've ever cut up, I crushed it up and pretty much put it all out for the trash in boxes in one week. the only bulk was the seats and motor which was parted out.
I think all those years with that shrink wrap may have helped it rot worse than if it had gotten some fresh air. I suppose is had sort of a greenhouse effect within the plastic covering.