Quite simple
Make a logging area that either the carpenter or a new class above farmer would tend to.
They would take seedlings produced by farms and plat them in an area.
They would then chop down the fully grown trees.
You would be able to choose what type of tree would be planted there or have it be a mix of trees where the logger would pick a random sapling from the available ones and it would be a mix of all.
Side suggestions.
More tree variation, they are all roughly the same colors and its boring.
More tree types?
Products with wood in them would look different based on what type of wood used to craft them.