You will often see comments regarding tree planting, as a solution for carbon removal, being criticized with a deep misunderstanding.
The criticism being thrown around is that the tree will release all the carbon back into the atmosphere once it decomposes and that growing trees is therefore not a valid way of permanently removing and storing carbon. The follow up ideas are quite ridiculous. “We need cut the trees down and bury them, deep in the earth, after they are grown”…etc
The idea with planting trees is to extend the existing forest biomes, and bring them closer to the original size they were before humans clear-cut them for lumber.
The best way to think of it is that any square acre of forest always has a certain amount of organic life in it. The forest canopy, the understorey, the shrub layer, the forest floor and the soil all store carbon. When a tree,a shrub, or a mushroom die, they release carbon back into the atmosphere, but they also make space for more life. You could say that a certain amount of carbon is always locked into the net cycle of life/lives within that square acre. The same would not be true if it was a parking lot.
Of course, it’s not only about forests. The same is true for all the different biomes.