[nemo44x]

> The main reason old growth trees have tight rings is not that the tree is growing slowly

No, it really is. Old pine from and some hardwoods grew in densely populated forests and there was a fight for sunlight. This severely limited how quickly the trees could grow per year resulting in tighter rings and far superior lumber.

Tree plantations are specced out to plant trees the perfect distance from each other so they can grow super fast. Spiked with fertilizers a pine can be harvested in year 15 for modern lumber. It's amazing how fast they can grow trees with enough sunlight and food.