The three parts of this area are mostly in the Till Plains Section of the Central Lowland Province of the Interior Plains.
The western third of the western part is in the Highland Rim Section of the Interior Low Plateaus Province of the Interior Plains.
The eastern half of the eastern part is in the Kanawha Section of the Appalachian Plateaus Province of the Appalachian Highlands.
55% of this area within Indiana.
45% of this area within Ohio.
Total Land Area 4,550 square miles (11,795 square kilometers).
North Vernon, Seymour, Versailles, Madison, and New Albany, Indiana.
Fayetteville, Batavia, and Hillsboro, Ohio.
Jackson-Washington State Forest, Starve Hollow State Beach, Hardy Lake State Recreational Area, Muscatatuck and Big Oaks National
Wildlife Refuges, and Versailles State Park are in the part of this area in Indiana.
Stonelick, East Fork, and Cowan State Parks and Fort Hill State Memorial are in the part in Ohio.
Middle Devonian to Early and Middle Mississippian bedrock occurs in the western part of the area; Ordovician, Silurian, and Devonian bedrock occurs in the southeastern part; and Middle to Late Mississippian bedrock occurs in the northeastern part.
Bedrock outcrops are common on the bluffs along rivers and the major tributaries. They also are evident at the base of steep slopes along minor streams and drainageways.
This area is covered with Illinoian-age loess and glacial till or outwash. The loess ranges from about 3 to 7 feet (1 to 2 meters) in thickness on stable summits and does not occur on some of the steeper slopes. Acid outwash and alluvial deposits are on some of the stream terraces along the major tributaries.
The major streams and rivers have well defined valleys with broad flood plains and numerous stream terraces. The flood plains along the smaller streams are narrow. Broad summits are nearly level to gently sloping.Topography -
Elevation ranges from 320 to 1,250 feet (100 to 380 meters). Relief is typically 10-50 feet (15-30 meters).
The average annual precipitation in this area is 37 to 46 inches (940 to 1,170 millimeters).
Most of the rainfall occurs as high-intensity, convective thunderstorms.
The average annual temperature is 48 to 57 degrees F (9 to 14 degrees C).
The freeze-free period averages about 190 days and ranges from 155 to 225 days.
* this is the percent of area drained by each named hydrologic unit
The Little Miami River, a National Wild and Scenic River, flows along the west edge of this area in Ohio.
|Public supply||surface water||1.9%||ground water||2.8%|
|Livestock||surface water||0.1%||ground water||0.2%|
|Irrigation||surface water||0%||ground water||0%|
|Other||surface water||94%||ground water||0.8%|
Total daily withdrawls average 1,180 million gallons per day (4,465 million liters).
4% Ground water sources
96% Surface water sources
Reservoirs are one of the sources of industrial and municipal water use. Surface waters are suitable for almost all uses.
The primary source of ground water in the part of this area in Indiana is the fractured limestone in the Silurian-Devonian aquifer. Total dissolved solids in the water is 513 parts per million (milligrams per liter). Also, its median level of iron is about 1,100 parts per billion (micrograms per liter), which is over three times the national secondary (esthetic) standard for drinking water.
In the area of Ohio wells rely on the Shaly Carbonate aquifer. This aquifer has water that is very similar in quality to the water in the bedrock aquifer in Indiana, but has lower iron content.
The soils are deep or very deep, loamy, silty, or clayey, and can range from well drained to poorly drained.
|Glossaqualfs||Avonburg, Clermont, Cobbsfork series||on broad, flat till plains.|
|Fragiudalfs||Cincinnati, Homewood, Nabb, Rossmoyne, Weisburg series||on side slopes on till plains or slopes underlain by bedrock residuum.|
|Hapludalfs||Blocher, Bonnell, Hickory series||on side slopes on till plains.|
|Hapludalfs||Cana, Grayford, Jessup series||slopes that are underlain by bedrock residuum.|
|Eutrudepts||Haymond, Oldenburg, Wilbur, Wirt series||formed in alluvium on flood plains.|
|Endoaquepts||Holton and Stendal series||formed in alluvium on flood plains.|
|Fluvaquents||Birds, Bonnie, Wakeland series||formed in alluvium on flood plains.|
Drier soils support White oak, black oak, red oak, hickory, yellow-poplar, ash, sugar maple, and black walnut grow on the better drained sites.
Moister soils support Pin oak, shingle oak, sweetgum, and black oak. Sedge and grass meadows are on some lowland sites.
Some of the major wildlife species include whitetailed deer, coyote, gray and red fox, beaver, mink, raccoon, opossum, great horned owl, bobwhite quail, and wood duck.
|61% -||Cropland||- private|
|9% -||Grassland||- private|
|17% -||Forest||- private|
|8% -||Urban development||- private|
|2% -||Water||- private|
|3% -||Other||- private|
Winter wheat, corn, soybeans, grain sorghum, and other feed grains are the principal crops. Some tobacco and apple orchards.
The major resource concerns include water erosion, flooding, wetness; maintenance of the content of organic matter in the soils and productivity of the soils.
Conservation practices on cropland generally include surface and subsurface drainage systems, crop residue management, filter strips, cover crops, and nutrient and pest management. Woodland management practices, such as exclusion of grazing and timber stand improvement, are important for timber production.