So what I have to do is sink a steel wedge into the large stump with a sledge hammer. Then with the hammer side of the maul I pound and pound and pound between 5 to 20 times before the chunk of beech splits open.
Even cutting and splitting easier wood in any reasonable timeframe requires an iron axe at the very least. Copper would be way too soft. Bronze, maybe, but still pretty soft.
Without iron, we would stare helplessly at trees. They would be solid, enduring objects we had little influence over. Sure we could take down a tree with stone or copper, but it would take so long as to be nearly impractical. And once down, then would come the daunting task of hewing it into timber or sectioning it into firewood. And forget about working with wood with any precision to make wheels or furniture or wooden machinery...as for clearing the land for cultivation, forget about it.
Without that one material, Iron, all the heating, industiral, and constructive benefit of wood would be locked up into solid, seemingly impregnable objects. We'd be pretty helpless to do anything to or about the trees in the world.