Conversion of forest to non-forest. Afforestation Artificial establishment of forest on lands that previously did not carry forest within living memory. Reforestation Artificial establishment of forest on lands that carried forest before. Footnote 10 on page 5.14 of the Reference Manual implies a different definition of reforestation, but this definition has not been used here. Potential crown cover refers to the state of existing vegetation at maturity under continuation of current land use.
Definition excludes land that is used predominantly for agricultural practices.
A key difference between the FAO and most of the other scenarios is that the FAO definition of reforestation includes artificial regeneration of tree cover after a clearing. Such regeneration includes natural regeneration, natural regeneration enhanced by planting, coppice sprouting, and planting or seeding. We interpret the FAO definition of reforestation to include regeneration after clearing. The IPCC scenario is extracted from the Glossary of the IPCC Reporting Guidelines. These guidelines do not include a definition of a forest, however, which limits their direct applicability.