“Get plenty of sleep, stay hydrated, and eat regular meals”
So generally speaking, if you were to look at a cross section of a mature tree, you would see the sapwood (the outer ring section of a woody stem, branch, or trunk. this is considered the living part which contains a variety of active cells, and where water and dissolved minerals are transported between the roots and the crown) and the heartwood (the centre inner section. this is considered the dead part and is usually of a darker colour, it is more resistant to insect attacks and decay)
All wood starts off as sapwood, as they become bigger the centre slowly ‘dies’ and becomes the stronger and tougher heartwood, helping to strengthen the structural integrity of the tree.
Heartwood are quite resistant to fire and burning, but some when smouldered release distinct aromatic smells often used as incenses. Lakawood is an example, the local reddish fragrant wood are often powdered and mixed to make joss sticks.