List of ecoregions in Wisconsin

The list of ecoregions in Wisconsin are listings of terrestrial ecoregions (see also, ecosystem) in the United States' State of Wisconsin, as defined separately by the United States Environmental Protection Agency (USEPA), and the World Wildlife Fund.

The USEPA ecoregion classification system has four levels, but only Levels I, III, and IV are shown on this list. Level I divides North America into 15 broad ecoregions (or biomes). Wisconsin is within the Eastern Temperate Forest, and in the Great Plains, Level I regions. Level IV ecoregions (denoted by numbers and letters) are a further subdivision of Level III ecoregions (denoted by numbers alone).

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