Phytogeographically, Poland belongs to the Central European province of the Circumboreal Region within the Boreal Kingdom. According to the World Wide Fund for Nature, the territory of Poland belongs to three Palearctic Ecoregions of the continental forest spanning Central and Northern European temperate broadleaf and mixed forest ecoregions, as well as the Carpathian montane conifer forest. The most common deciduous trees found across the country are oak, maple, and beech; the most common conifers are pine, spruce, and fir. An estimated 68.7% of all forests are coniferous.