Afforestation
Afforestation is the establishment of forest through planting or deliberate seeding on land that was previously under another land use. Under Food and Agriculture Organization reporting, it is a land-use change from non-forest to forest. Forest expansion through natural succession is classified separately as natural expansion, rather than afforestation.
In simple terms
Afforestation uses planting or deliberate seeding to establish forest on land previously classified as non-forest, such as some former agricultural areas. Natural succession on non-forest land is reported separately as natural expansion. Because the starting ecosystem may have valuable biodiversity and services, adding trees is not automatically beneficial. Species choice, water demand, soil, fire risk, local livelihoods, tenure, and previous habitat all matter. Reporting frameworks apply explicit forest-area, height, canopy, and duration thresholds, which should be stated when afforestation is measured or claimed.
Why it matters
Afforestation can expand forest resources, store carbon, protect soils, and support livelihoods, but poorly located projects can damage native grasslands or peatlands, intensify water scarcity, or create vulnerable monocultures. Distinguishing it from reforestation makes land-use accounting clearer and encourages assessment of what existed before trees were established.
Example
For example, establishing a long-term forest on former cropland may be afforestation. Before planting, planners would assess whether forest is ecologically suitable, how the project affects food production and water, which species support resilience, and whether local rights and land uses are protected.
How it differs
Reforestation
Afforestation establishes forest on previously non-forest land; reforestation restores forest cover where the land remained classified as forest.