I acknowledge the existence of multiple planes in a realm, and interconnected realms in my main canons. Without going into too much detail, there's a few fundamental concepts I have for it.
For multiple planes in a realm, it's along the lines of differing wavelengths; every entity is the sum of its soul, and the soul is capable of existing in multiple planes. It is a physical form that binds the soul to one plane or another. Two primary ones exist; the others are more like different dimensions. The main one is material, where all physical actions occur, and the second is minus the material part where souls directly interact (most are incapable of moving to this second level). The forest, being material, doesn't actually exist in the second plane, but the souls of the trees do. If you "burn down the forest" in this plane, the trees would exist without souls; there would be no special attributes to them, and they would be influenced by what happened in the other plane. Those attributes are another discussion altogether, but that's how I approach it.
Physical materials in the second plane are just representations and aren't actually affected in the material plane. I'll use computing as an example... the material plane is the hard drive where everything actually exists, on the other side is RAM where everything is temporary, 100% changeable and ultimately can be unloaded and reloaded altogether.