I want to know the answer to the following question:
What hides the stubs of a tree's lost limbs from being visible later in its life?
All the background I'm provided with is that "Since in most uses of wood, knots are defects that weaken the timber and interfere with its ease of working and other properties, it follows that a given piece of sapwood, because of its position in the tree, may well be stronger than a piece of heartwood from the same tree.". Is that enough to answer the question?
Answer: no