In my experience itís not the wood the woodpeckers love, but the carpenter bees living in the wood. If carpenter bees are not native to your area, then you need to find out what particular delicacy they enjoy. This is the way it is in SE Pennsylvania.
Carpenter bees make ľ inch holes in the wood, tunneling at a right angle just beneath the surface. Iíve seen them work. They dig very fast, and even pressure-treated wood does not deter them. They donít do it to eat the wood, just to build a home.
I once was woken up every morning to the sound of a woodpecker pecking at my aluminum capping, to which I thought I was dealing with an insane bird. I happened to mention it to an exterminator, who told me of the carpenter bees. Sure enough, carpenter bees were found in the attic, and when they were removed from the property, said bird, too, moved on.
Since then I have seen countless situations, many times in decks and porches, where the small ľ inch hole made by the carpenter bee has been pecked out by the woodpecker.