Home » Regions » North America » Eastern Temperate Forests » Ozark, Oauchita-Appalachian Forests » Western Allegheny Plateau

Western Allegheny Plateau

Page contents

To check where a specific point lies, you can look it up in our Ecoregion Locator.

Map Legend & Subregion List

This list will help you navigate the regions in case you have problems with viewing or clicking the interactive map above.

NameColor on MapEPA Code‡
Permian Hills70a
Monongahela Transition Zone70b
Pittsburgh Low Plateau70c
Knobs-Lower Scioto Dissected Plateau70d
Unglaciated Upper Muskingum Basin70e
Ohio/Kentucky Carboniferous Plateau70f
Northern Forested Plateau Escarpment70g
Carter Hills70h

† Status: ✓ = Complete ○ = Needs Image … = Incomplete ∅ = Stub Only

This code refers to the US EPA's Level 4 ecoregion codes for the continental U.S., see here.


Partially Complete
With Images
Complete w/ Images

Get involved! You can help our ecoregion articles progress faster. Help us find photos of these regions. Contact us if you have any additions or corrections to any of these articles. You can also donate to support our ongoing work.

About the Western Allegheny Plateau

The Western Allegheny Plateau is a broad region extending roughly northeast-southwest from southwest Pennsylvania through much of northwest West Virginia and southeast Ohio, into northeastern Kentucky.

This area was not glaciated in the recent ice age, and the terrain mostly consists of a heavily-dissected plateau with rugged hills. Although the topography is relatively steep when viewed on a small scale, taken on a large scale this region is quite flat, lacking the higher elevations of the Appalachian ridges to the southeast. The underlying bedrock is sedimentary, mostly from the Carboniferous period.

This region has a humid continental climate with warm to hot summers and cold winters. The original forest cover here consisted of mixed mesophytic forest, with some smaller areas of Appalachian oak forests. Dominant tree species include chestnut oak, red maple, white oak, black oak, American beech, tuliptree, sugar maple, various ash species, American basswood, buckeye, and eastern hemlock.

Nowadays, this region is mostly forested, with small amounts of agriculture, including livestock and dairy farming, and cultivation of hay, corn, small grains, and tobacco. There is some logging and forestry in the area, as well as some protected national forests. Coal mining is extensive, causing extensive environmental problems including degradation of waterways. Pittsburgh is the largest city in this region, which also contains numerous smaller cities.

This area is bordered to the southeast by the more rugged and higher-elevation Central Appalachians and to the northwest by the glaciated and much flatter Erie Drift Plain. Southwest of that, but also to the northwest, this region also shares a small border with the Eastern Corn Belt Plains, and south of that, to the west by the Interior Plateau. There is also a small border to the southwest with the Southwest Appalachians.

Plant Lists & In-Region Search


1. Wiken, E., Griffith, G. "North American Terrestrial Ecoregions - Level III", Commission for Environmental Cooperation, (2011) Web.