A set of forests that stays the same size, i.e. some trees fall down and rot or get cut down and burned while new trees sprout or get planted, so that the total amount of biomass in these forests is more or less stable long-term is not a carbon removal technology but simply a carbon store. To remove carbon, the amount of biomass needs to increase... so we essentially need to cut down trees and somehow store their carbon instead of releasing it back into air through decay or burning.