In Finland, forestry land is divided into three growth categories. On forest land, or productive forest, the average increment (tree growth) is over one cubic metre per year per hectare. On poorly productive forest land this figure is 0.1–1 cubic metres and on unproductive land under 0.1 cubic metres per year.
Forest land and poorly productive forest land together are often called forest. According to the firest definition by FAO, forest is an area of land of spanning more than 0.5 hectares with trees higher than 5 meters and a canopy cover of more than 10 percent, or trees able to reach these thresholds in situ. As to the Finnish definition, productive forest and around half of the poorly productive forest together correspond the FAO forest definition.