I'm starting to be of the opinion that with world population pushing on toward 7 billion people, wood is no longer a renewable resource, at least not the kind of wood that used to be used for boats and paddles. It's turning into a material used primarily in the manufacture of luxury items.
Yesterday, my shop partner Sebastian was working on some shelving he had bought at Ikea and was modifying. He sawed through the shelf which was about 2 inches thick. The flat surfaces were made of 1/8 inch of some composite. The sides were faced in plastic. The perimeter was made of chip board and the hollow interior was filled with a paper honeycomb material.
I suspect that in the northern latitudes of the world where trees are small, they do not bother cutting trees into boards. I suspect that they feed it directly into a chipper and then glue the chips into particle board. Wood is the feedstock for an industrial process.
Of course you can't build boats out of the kind of stuff that Ikea makes furniture out of. You need actual wood for that.
Same sort of dispiriting trends that have developed for boat building wood have also developed for paddle building wood. My supplier has piles of Sitka spruce in his warehouse, but he hasn't re-ordered in a while due to the recession and each time I go to get more wood for paddles, I have to pick through more boards to find the few good ones suitable for paddles.
So yes, wood is renewable if you're talking of the stuff you can plant now and harvest in ten years, but boat building wood has always been cut from trees that have had a hundred years of growth or more. Once we cut all of that down, it will be the twenty second century until we can see some more of it, assuming of course that anyone lets a tree stand that long.