The Boston Mountains is a Level III ecoregion designated by the Environmental Protection Agency (EPA) in the U.S. states of Arkansas and Oklahoma. Part of the Ozarks, the Boston Mountains are a deeply dissected plateau. The ecoregion is steeper than the adjacent Springfield Plateau to the north, and bordered on the south by the Arkansas Valley. The Oklahoma portion of the range is locally referred to as the Cookson Hills. There are several theories of how the mountains were named, though apparently none are related to the Massachusetts city.
The ecology of California can be understood by dividing the state into a number of ecoregions, which contain distinct ecological communities of plants and animals in a contiguous region. The ecoregions of California can be grouped into four major groups: desert ecoregions, Mediterranean ecoregions, forested mountains, and coastal forests.
The Appalachian mixed mesophytic forests is an ecoregion of the temperate broadleaf and mixed forests biome, as defined by the World Wildlife Fund. It consists of mesophytic plants west of the Appalachian Mountains in the Southeastern United States.
The Ozark Mountain forests are a temperate broadleaf and mixed forests ecoregion of the central United States delineated by the World Wide Fund for Nature. The ecoregion covers an area of 23,900 square miles in northern Arkansas and eastern Oklahoma.
The Appalachian–Blue Ridge forests are an ecoregion in the Temperate broadleaf and mixed forests Biome, in the Eastern United States. The ecoregion is located in the central and southern Appalachian Mountains, including the Ridge-and-Valley Appalachians and the Blue Ridge Mountains. It covers an area of about 61,500 square miles (159,000 km2) in: northeast Alabama and Georgia, northwest South Carolina, eastern Tennessee, western North Carolina, Virginia, Maryland, and central West Virginia and Pennsylvania; and small extensions into Kentucky, New Jersey, and New York.
The Klamath Mountains ecoregion of Oregon and California lies inland and north of the Coast Range ecoregion, extending from the Umpqua River in the north to the Sacramento Valley in the south. It encompasses the highly dissected ridges, foothills, and valleys of the Klamath and Siskiyou Mountains. It corresponds to the Level III ecoregion designated by the Environmental Protection Agency and to the Klamath-Siskiyou forests ecoregion designated by the World Wide Fund for Nature.
The Ozark Highlands is a Level III ecoregion designated by the Environmental Protection Agency (EPA) in four U.S. states. Most of the region is within Missouri, with a part in Arkansas and small sections in Oklahoma and Kansas. It is the largest subdivision of the region known as the Ozark Mountains, less rugged in comparison to the Boston Mountains in Arkansas, the highest part of the Ozarks.
The Upper Midwest forest–savanna transition is a terrestrial ecoregion that is defined by the World Wildlife Fund. An oak savanna plant community located in the Upper Midwest region of the United States, it is an ecotone between the tallgrass prairies to the west and the temperate deciduous forests to the east. A part of the Upper Mississippi River basin, it is considered endangered with less than 5% of the original ecosystem remaining intact, due mostly to overgrazing and conversion to agriculture.
The Mississippi lowland forests are a temperate broadleaf and mixed forest ecoregion in the eastern United States, covering an area of 112,300 km2 (43,400 sq mi).
The California montane chaparral and woodlands is an ecoregion defined by the World Wildlife Fund, spanning 7,900 square miles (20,000 km2) of mountains in the Transverse Ranges, Peninsular Ranges, and Coast Ranges of southern and central California. The ecoregion is part of the larger California chaparral and woodlands ecoregion, and belongs to the Mediterranean forests, woodlands, and scrub biome.
The East Central Texas forests (33) is a small temperate broadleaf and mixed forests ecoregion almost entirely within the state of Texas, United States. The northern forests perimeter is partially within the southeast Oklahoma border.
The Eastern Great Lakes lowland forests is a temperate broadleaf and mixed forest ecoregion of North America, as defined by the World Wildlife Fund. It lies mostly in south and eastern Ontario and Quebec in Canada, and Upstate New York and Vermont in the United States.
The Arizona Mountains forests are a temperate coniferous forests ecoregion of the southwest United States with a rich variety of woodland habitats and wildlife.
The central forest–grasslands transition is a prairie ecoregion of the central United States, an ecotone between eastern forests and the North American Great Plains. It is a classification defined by the World Wildlife Fund.
The Middle Atlantic coastal forests are a temperate coniferous forest mixed with patches of evergreen broadleaved forests along the coast of the southeastern United States.
The Southeastern mixed forests are an ecoregion of the temperate broadleaf and mixed forest biome, in the lower portion of the Eastern United States.
The Interior Low Plateaus are a physiographic region in eastern United States. It consists of a diverse landscape that extends from north Alabama across central Tennessee and Kentucky into southern Illinois, Indiana, and Ohio. Its natural communities are a matrix of temperate forests, woodlands, and prairies.
The Southeastern conifer forests are a temperate coniferous forest ecoregion of the southeastern United States. It is the largest conifer forest ecoregion east of the Mississippi River. It is also the southernmost instance of temperate coniferous forest within the Nearctic realm.
The Western Allegheny Plateau is an ecoregion of the Temperate broadleaf and mixed forests Biome, located on the western Allegheny Plateau and in the Appalachia region of the Eastern United States.
The Arkansas Valley is a Level III ecoregion designated by the Environmental Protection Agency (EPA) in the U.S. states of Arkansas and Oklahoma. It parallels the Arkansas River between the flat plains of western Oklahoma and the Arkansas Delta, dividing the Ozarks and the Ouachita Mountains with the broad valleys created by the river's floodplain, occasionally interrupted by low hills, scattered ridges, and mountains. In Arkansas, the region is often known as the Arkansas River Valley, especially when describing the history and culture of the region.
