In northern Minnesota, where both deciduous and coniferous trees commonly occur, many of the forests contain mixtures of deciduous (broad-leaved) and coniferous (needle-leaved) tree species and are therefore called mixed forests.

The most common coniferous trees in mixed forests are white spruce, balsam fir, and the pines (jack pine, red pine, and white pine). These are usually mixed with deciduous trees such as paper birch, trembling apsen, red maple, or black ash.

Widespread logging by European settlers and the subsequent loss of pine seed sources caused a conversion from large acreages of formerly coniferous forest to mixed coniferous-deciduous forest and deciduous forest.