The area is only about one-third forested, with pressure from human agriculture leaving the rest in a patchwork of traditional pasture, meadows, wetlands.

The ecoregion is in the temperate broadleaf and mixed forest biome, and the Palearctic realm, with a Humid Continental climate.

The terrain is mostly flat lowlands in the center, hilly moraine-dominated in the north, and uplands to the south along the Carpathian Mountains.

[2] Also to the north are the Baltic mixed forests of oaks, hornbeam, and linden trees on flat, acidic soils.

[4][5] The summers become hotter and the winters colder as you move east across the ecoregion, due to the movement towards the center of the continent ("continentality").

[3] The most common tree in the ecoregion, covering half of the forested area, is Scots pine (Pinus sylvestris), Norway spruce (Picea abies), English oak (Quercus robur), Sycamore maple (Acer pseudoplatanus), and Silver birch (Betula pendula), which has been planted extensively over the past 200 years.

[3] The truly mixed deciduous forests which mostly consist of Quercus robur, Quercus petraea, Picea abies, Alnus glutinosa, Fagus sylvatica, Taxus baccata, Acer pseudoplatanus, Malus sylvestris, Viburnum lantana, Fraxinus excelsior, Tilia cordata, Aesculus hippocastanum, Rhamnus cathartica, Ulmus glabra, Ulmus minor, Populus alba, Salix alba, Pinus sylvestris, Betula pendula, Populus tremula, Populus nigra, Juglans regia, Juniperus communis, Prunus padus and Corylus avellana, have been replaced mostly by agriculture.

In mid-16th century Grand Duke of Lithuania and King of Poland Sigismund II Augustus pronounced a death penalty for poaching a European bison in Białowieża.