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Summary Table: Characteristics of Ecoregions of and

39. OZARK HIGHLANDS 47. WESTERN PLAINS Level IV Ecoregion Physiography Geology Climate Potential Natural Vegetation Land Use and Land Cover Level IV Ecoregion Physiography Geology SoilClimate Potential Natural Vegetation Land Use and Land Cover Temperature/ Frost Free Mean Temperature Temperature/ Precipitation Frost Free Mean Temperature Area Elevation/ Surficial material and bedrockOrder (Great Groups) Common Soil Series Area Elevation/ Surficial material and bedrockOrder (Great Groups) Common Soil Series Moisture Mean annual Mean annual January min/max; Moisture Mean annual Mean annual January min/max; (square Local Relief (square Local Relief Regimes (inches) (days) July min/max, ( F) Regimes (inches) (days) July min/max, ( F) miles) (feet) ° miles) (feet) ° 39a. Springfield 4933 Gently sloping to irregular plain. Karst 800-1700 Cherty clay solution residuum and areas of Ultisols (Paleudults, Clarksville,Goss, Doniphan, Mesic 40-42 150-180 26-46; Big bluestem/Indiangrass , post- Mix of woodland,pastureland and 47a. Northwest Iowa 4385 Irregular plains. 1200-1600 Moderate to thick over clay-loam till. Mollisols (Hapludolls) Galva, Primghar, Sac Mesic/ 27-29 140-150 5-27; Big bluestem-Indiangrass prairie, little Cropland with corn, , Plateau features. / thin loess. Mississippian cherty limestone. Fragiudults) Viraton, Wilderness, some 66-90 blackjack woodland and white- limited cropland. Historical lead and Loess Dendritic streams. / Cretaceous shale, sandstone, and limestone, Udic 62-87 bluestem-Indiangrass prairie, and alfalfa, and other feed grains. Perennial spring-fed streams. 50-150 Alfisols (Fragiudalfs, Scholten, Tonti, Hector, Thermic/ black oak forest. zinc mining. Urban and suburban at 100-200 some Precambrian quartzite. limited areas of bur-oak woodland. Hapludalfs, Paleudalfs) Keeno, Creldon, Hoberg, Udic, Springfield and Joplin. Inceptisols (Dystrudepts) Bolivar Aquic 47b. Des Moines Lobe 12214 Smooth to irregular plains. 900-1500 Loamy till with no loess cover. Ground, Mollisols (Hapludolls) Clarion, Nicollet,Webster Mesic/ 28-31 145-1608-28; Big bluestem-Indiangrass prairie, Cropland with corn, soybeans, and Dendritic streams and drained / stagnation and end moraines. Udic 62-87 cordgrass wet prairie, and limited areas other feed grains. 39b. River Hills 540 Dissected hills, entrenched valleys and 900-1400 Cherty clay solution residuum and areas of Ultisols (Paleudults, Clarksville, Noark, Nixa, Mesic/ 41-42 130-180 27-47; Post-blackjack oak woodland, post- Forestry, recreation and poultry wetlands. 50-100 of bur-oak woodland. areas ranging from rolling,irregular / thin loess. Mississippian cherty limestone, Fragiudults) Goss, Doniphan, Tonti Udic 66-90 black oak woodland, and white-black . plains to steep slopes. Karst features. 200-300 with some Devonian, shales (Chattanooga) Alfisols (Paleudalfs) oak forest. 47c. Iowan Surface 8515 Irregular to smooth plains. 900-1200 Thin loess over loamy till. Mollisols (Hapludolls, Kenyon, Flood,Clyde Mesic/ 31-33 145-1556-24; Big bluestem-Indiangrass prairie,areas Cropland with corn, soybeans, and Dendritic, deeply entrenched streams. and limestone,a few windows of Ordovician Low gradient streams. / Devonian and Silurian limestone and Argiudolls) Udic 62-84 of bur-oak-mixed oak and other feed grains. dolomite in valleys. 50–100 dolomite. woodlands. 39c. White River Hills 3512 Dissected hills and entrenched valleys. 600-1600 Thin cherty clay solution residuum in the Ultisols (Paleudults, Mano, Captina, Clarksville, Mesic/ 42-44 150-180 25-48; Little bluestem-sideoats alkaline glade, Forestry and recreation. Pastureland 47d. Missouri Alluvial 2172 Smooth to irregular alluvial plain. 600-1100 Alluvium over Pennsylvanian and Cretaceous Mollisols (Hapludolls, Haynie,Leta, Waldron, Mesic/ 26-36 150-1806-36; Northern floodplain forest, pin oak Cropland with corn, soybeans, and Steep slopes and narrow valleys. Karst / west and very thin cherty silty to sandy clay Fragiudults, Hapludults) Doniphan, Nixa, Arkana, Udic 66-90 post-blackjack oak woodland, white- in eastern half. Plain Channelized streams. / shale, sandstone and limestone. Endoaquolls) Blake, Booker Udic 62-91 forest, and cordgrass wet prairie. other feed grains. features. 200-600 solution residuum in the east. Ordovician Alfisols (Hapludalfs) Moko, Gassville, Ocie, black oak forest. 0-50 Entisols (Udifluvents, Dendritic, deeply entrenched streams. dolomite, with some Ordovician sandstone. Mollisols (Hapludolls) Bardley Fluvaquents) Mississippian limestone on ridgetops. Glades 47e. Steeply Rolling 5753 Open low hills. 800-1300 Moderate to thick loess, 25 to 50 feet, over Mollisols (Hapludolls, Marshall, Exira, Shelby, Colo Mesic/ 27-34 150-180 14-35; Big bluestem-Indiangrass prairie, and Cropland with corn, soybeans, and are Ordovician limestone or dolomite. Loess Prairies Intermittent and perennial streams, / clay loam till. Pennsylvanian shale, Argiudolls, Endoaquolls) Udic 66-90 white oak-red oak woodland,bur-oak other feed grains. 39d. Central Plateau 6820 Irregular plains with broad summits 800-1600 Thin to thick cherty silty to sandy clay Ultisols (Paleudults, Viraton, Clarksville, Mesic/ 40-44 150-180 24-46; Little bluestem/Indiangrass prairie, Pastureland,forestry, and limited many channelized. 100-300 sandstone and limestone. mixed woodland. and moderately steep valleys. Karst / solution residuum and large areas of thin Fragiudults, Hapludults) Lebanon, Goss, Doniphan, Udic 66-90 post-blackjack oak woodland, and cropland with main crops of forage 47f. Rolling Loess 17858 Irregular plains to open low hills. 700–1300 Moderate to thick loess, generally less than Mollisols (Argiudolls, Sharpsburg, Shelby, Colo, Mesic/ 30-37 160-180 17-38; Mosaic of big bluestem-Indiangrass Cropland with corn, soybeans, and features are extensive with large 50-150 loess. Ordovician dolomite, some outliers of Alfisols (Fragiudalfs, Arkana, Moko, Gassville, black-scarlet oak woodland. and feed grains for livestock. Fire Prairies Intermittent and perennial streams, / 25 feet, over clay loam till. Pennsylvanian Endoaquolls, Hapludolls) Marshall, Higginsville, Udic 66-91 prairie,and bur-oak woodland. other feed grains as main crops. sinkhole areas. Mississippian-aged limestone in the western Hapludalfs, Paleudalfs) Gepp, Agnos, Captina, Union clay production. many channelized. 100–200 and Cretaceous shale, sandstone and Alfisols (Hapludalfs) Sibley, Exira, Knox Some pastureland, urban at Intermittent headwater streams, . Pennsylvanian shales and clays in areas Mollisols (Hapludolls) limestone. City. sinkholes, ponds. with less relief. 1654 Open hills and bluffs. 1000-1500 Thick loess, 60 to 150 feet over clay-loam Mollisols (Hapludolls) Monona, Ida, Hamburg, Mesic/ 27-33 150-180 13-35; Mosaic of bur-oak woodland and big Cropland with corn, soybeans, and 5040 Moderately dissected hills. Steep 600-1100 Thin to very thick cherty clay decomposition Ultisols (Paleudults, Bardley, Goss, Gasconade, Mesic/ 38-42 150-180 23-45; Mainly post-blackjack oak woodland to Forestry, recreation and pastureland. 47m. Western Loess 39e. Osage/Gasconade Intermittent and perennial streams. / till. Pennsylvanian shale, sandstone and Entisols (Udorthents) Napier Udic 67-91 bluestem-Indiangrass prairie. other feed grains, and pastureland. slopes and narrow valleys. Karst / and solution residuum. Ordovician dolomite Fragiudults) Clarksville, Doniphan, Udic 67-91 the north with white-black oak forest, Hills Hills 100-300 limestone in southern half of region; features. 150-300 with some sandstone (Gasconade Formation), Alfisols (Hapludalfs) Bucklick, Caneyville, white oak forest, and an increase in Cretaceous shale, sandstone and limestone in Dendritic spring-fed perennial streams. sandstone (Roubidoux Formation), and Mollisols (Hapludolls) Gatewood, Captina, Niangua shortleaf pine-oak forest to the south. the northern half. dolomite (Jefferson City-Cotter Formation). Some scattered Mississippian limestone in the west. 39f. St. Francois 1590 Steep, irregular hills, bedrock knobs 600-1700 Silty clay loam decomposition and solution Ultisols (Hapludults, Irondale, Killarney, Delassus, Mesic/ 40-44 120-150 25-45; Post-blackjack oak woodland with little Forestry in timbered areas and Knobs and Basins and intervening basins. / residuum mantled with thin loess. Areas of Fragiudults, Paleudults) Crider,Fourche, Bucklick, Udic 64-91 bluestem prairie and glade areas in pastureland and grazing in valleys Small rivers and perennial streams. 300-1000 sandy silty saprolite. Precambrian granite, Alfisols (Hapludalfs, Syenite, Clarksville, valleys and basins. and basins. Historically, areas of rhyolite, and intermediate rocks. Cambrian Paleudalfs, Fragiudalfs) Wilderness, Captina extensive lead mining along with dolomites and some sandstones in basins. associated copper,silver, cobalt, and zinc mining. 52. 39g. Meramec River 1776 Hills and entrenched valleys. Steep 500-1300 Thin to thick sandy clay decomposition and Ultisols (Paleudults, Goss, Doniphan, Wilderness, Mesic/ 38-42 130-160 24-45; Shortleaf pine-oak forest, black-scarlet Forestry and recreation with areas of Level IV Ecoregion Physiography Geology SoilClimate Potential Natural Vegetation Land Use and Land Cover Hills slopes, narrow ridges, and narrow / solution residuum and thick silty clay and Fragiudults) Captina, Coulstone, Hobson, Udic 65-90 oak woodland and forest, and white iron and barite mining. Temperature/ Precipitation Frost Free Mean Temperature Area Elevation/ Surficial material and bedrock Order (Great Groups) Common Soil Series Moisture Mean annual Mean annual January min/max; valleys. Karst features. 150-300 clayey silt solution residuum with loess. Alfisols (Paleudalfs, Reuter oak forest. (square Local Relief Regimes (inches) (days) July min/max, ( F) Dendritic spring-fed perennial streams. Ordovician and Cambrian dolomite and Fragiudalfs) miles) (feet) ° sandstone. Some scattered exposures of Precambrian igneous rocks. 52b. Paleozoic Plateau/ 2806 Dissected hills, rolling to steep-sided 700–1200 Thin loess and patches of glacial drift over Alfisols (Hapludalfs) Fayette,Dubuque Mesic/ 32-34 140-155 8-24; Mosaic little bluestem-Indiangrass Pastureland, cropland, and Coulee Section valleys. / Silurian, Ordovician and Cambrian dolomite, Udic 62-82 prairie,bur-oak and white oak forests, woodland. Principal crops are feed 39h. Current River 3114 Hills and entrenched valleys. Steep 400-1300 Thin to thick sandy clay decomposition and Ultisols (Paleudults, Clarksville,Goss, Doniphan, Mesic/ 42-45 130-160 26-46; Shortleaf pine-oak forest, black-scarlet Forestry and recreation with some Perennial streams. 300–500 shale, sandstone, and limestone. and areas of maple-basswood forests. grains and forage for dairy cattle and Hills slopes, narrow ridges, and narrow / solution residuum and thick silty clay and Fragiudults, Hapludults) Captina, Macedonia, Gepp, Udic 64-90 oak woodland and forest, and white areas of lead, zinc, copper, and other livestock. valleys. Karst features. 200-400 clayey silt solution residuum. Ordovician and Alfisols (Paleudalfs) Tonti oak forest. manganese mining. Dendritic, deeply entrenched, spring- Cambrian dolomite and sandstone. Some fed perennial streams. scattered exposures of Precambrian igneous rocks. 39i. Eastern Ozark 1835 Moderately dissected hills and bluffs. 500-1100 Thin cherty clay decomposition and solution Ultisols (Paleudults, Bucklick, Caneyville, Mesic/ 38-44 130-160 25-44; Little bluestem-sideoats alkaline glade, Pastureland,woodland, and limited Border Some karst features. / residuum and thin to moderate loess mantle Hapludults) Gatewood, Hildebrecht, Udic 66-91 post-black jack oak woodland, and cropland with hay and forage crops. Dendritic, entrenched perennial 150-300 on uplands. Ordovician dolomite with some Alfisols (Hapludalfs, Weingarten, Goss, Lily, white-black oak woodland. streams. sandstone Mississippian limestone. Fragiudalfs, Paleudalfs) Minnith, Jonca, Loring, Poyner,Weingarten 39j. Black River Hills 1076 Broad,flat inter-stream divides and 300-900 Thick cherty sandy clay decomposition and Ultisols (Paleudults, Clarksville,Wilderness, Mesic/ 44-46 130-160 26-46; Shortleaf pine-oak woodland, post- Forestry, pastureland, and recreation. 72. INTERIOR RIVER VALLEYS AND HILLS Border moderately dissected hills. Karst / solution residuum and thick cherty clay Fragiudults) Captina Udic 66-92 blackjack oak woodland, and mixed Level IV Ecoregion Physiography Geology SoilClimate Land Use and Land Cover features. 100-300 solution residuum. Thin loess mantle on less Alfisols (Fragiudalfs) oak-sweetgum forest. Potential Natural Vegetation Temperature/ Precipitation Frost Free Mean Temperature Perennial streams and local riverine dissected areas. Ordovician dolomite and Area Elevation/ Surficial material and bedrock Order (Great Groups) Common Soil Series Moisture Mean annual Mean annual January min/max; (square Local Relief wetlands. sandstone. Regimes (inches) (days) July min/max, ( F) miles) (feet) ° 839 Smooth to gently sloping plains. 800-1100 Thin to moderate loess mantle. Thin cherty Alfisols (Hapludalfs) Menfro, Winfield,Haymond Mesic/ 38-40 150-180 26-42; Big bluestem-Indiangrass prairie, Cropland with hay and forage crops, 39k. Prairie Ozark 1033 Smooth to irregular alluvial plains. 425-550 Alluvium. Brown to gray silt, clay, sand, and Mollisols (Endoaquolls) Carlow, Portage, Chequest, Mesic/ 34-38 150-180 20-39; Cottonwood-willow riparian forest, pin Cropland with corn, wheat, Intermittent headwater streams. / clay solution residuum and thin cherty silty Inceptisols (Eutrudepts) Udic 68-91 bluestem-Indiangrass prairie, and post- and pastureland. 72d. Upper Border Channelized streams. / gravel. Thickness of alluvial and older fluvial Colo, Zook Udic 66-90 oak forest, cordgrass wet prairie. soybeans, and feed grains and hay 50-100 to sandy clay decomposition and solution blackjack woodland. Alluvial Plain 0-50 deposits more than 100 feet. for livestock. residuum. Ordovician dolomite and sandstone to the south, and Mississippian 72e. Middle Mississippi 207 Smooth to irregular alluvial plains. 300-425 Alluvium. Brown to gray silt, clay, sand, and Entisols (Udifluvents, Haynie,Waldron, BlakeMesic/ 38-44 180-200 26-44; Cottonwood-willow riparian forest, Cropland with corn, wheat, limestone to the north. Some areas of Alluvial Plain Channelized streams. / gravel. Thickness of alluvial and older fluvial Fluvaquents) Udic 68-92 green ash-elm-hackberry forest, pin soybeans, and feed grains and hay Devonian shale and sandstone. 0-50 deposits more than 100 feet. oak and swamp white oak forest. for livestock. 72f. River Hills 6993 Bluffs, valleys and low hills. Areas of 400-810 Thin cherty clay and silty to sandy clay Alfisols (Hapludalfs, Lindley,Keswick, Goss, Mesic/ 38-44 150-180 24-43; White-black oak woodland, white oak Cropland on uplands, pastureland, karst features. / solution residuum. Areas of clay loam till Paleudalfs) Bardley, Gasconade, Udic 66-91 woodland,and sugar maple-oak forest. woodland, and areas of urban at St. Perennial streams. 50-300 along the northern boundary along the Mollisols (Hapludolls) Cedargap, Menfro, Louis-St. Charles and Columbia- channelized. Missouri River and eastern boundary of the Inceptisols (Eutrudepts) Haymond, Winfield,Hatton Jefferson City. Feed grains and hay upper . Thin loess, 5 to 13 for livestock. feet, on uplands along bluffs. Alluvium along the Missouri River. Ordovician, Mississippian, and Pennsylvanian limestones, sandstones, and shales with considerable bedrock exposures throughout the region.

73. MISSISSIPPI ALLUVIAL PLAIN Level IV Ecoregion Physiography Geology SoilClimate Potential Natural Vegetation Land Use and Land Cover Temperature/ Precipitation Frost Free Mean Temperature Area Elevation/ Surficial material and bedrock Order (Great Groups) Common Soil Series Moisture Mean annual Mean annual January min/max; (square Local Relief Regimes (inches) (days) July min/max, ( F) miles) (feet) ° 73a. Holocene 702 Wide, smooth alluvial plain. Point 250-325 Unconsolidated silty,clayey, and sandy Entisols (Fluvaquents, Commerce, Caruthersville, Thermic/ 45-46 180-210 28-48; Oak-sweetgum forest, overcup oak- Extensive cropland with cotton, rice Meander Belts bars, meander belts, oxbows and / alluvium, 5 to 10 feet in depth over older Udifluvents) Hayti, Dundee Aquic, 68-92 water hickory forest, and tupelo- and soybeans. abandoned channels. 0-25 fluvial deposits 70 feet to greater than 100 Alfisols (Endoaqualfs) Udic cypress swamp forest. Extensive channelized streams and feet deep. Holocene deposits. 40. CENTRAL IRREGULAR PLAINS drained wetlands. Level IV Ecoregion Physiography Geology Soil Climate Potential Natural Vegetation Land Use and Land Cover 73b. Valley 2940 Wide,smooth to irregular alluvial 250-325 Unconsolidated silty alluvium and alluvial Alfisols (Epiaqualfs, Sharkey, Gideon, Sikeston, Thermic/ 44-48 180-210 28-48; Oak-sweetgum forest, overcup oak- Extensive cropland with cotton, rice Temperature/ Precipitation Frost Free Mean Temperature Trains plain. Interfluves, relict channels, and / sand,generally 5 to 15 feet in depth with Endoaqualfs, Hapludalfs) Lilbourn, Wardell, Dundee, Aquic, 68-92 water hickory forest, and tupelo- and soybeans. Area Elevation/ Surficial material and bedrockOrder (Great Groups) Common Soil Series Moisture Mean annual Mean annual January min/max; (square Local Relief terraces. 0-25 narrow sandy areas as deep as 50 feet. Older Entisols (Fluvaquents, Maldin, Dubbs, Clana Udic cypress swamp forest. Regimes (inches) (days) July min/max, ( F) miles) (feet) ° Extensive channelized streams and fluvial deposits greater than 100 feet deep. Udipsamments) drained wetlands. Alluvium covers Pleistocene sand and gravel, Mollisols (Endoaquolls) 40a. Loess Flats and 16976 Glaciated. Low hills and smooth 600-1200 Moderate loess over loamy till and clay loam Mollisols (Argiudolls, Lamoni, Shelby, Adair, Mesic/ 32-36 150-180 16-36; Mosaic of little bluestem-sideoats Cropland. Corn, soybeans, other glacial outwash. Till Plains plains. / till. Pennsylvanian sandstone,limestone, Hapludolls) Grundy,Lagonda,Armster, Udic 66-90 grama prairie,bur-oak woodland, and feed grains, and hay are principal Perennial streams with many 100-300 shale. Also Mississippian limestone in Iowa. Alfisols (Hapludalfs, Snead,Gara, Armstrong, chinkapin oak woodland. crops. Historic coal mining. channelized. Epiaqualfs, Paleudalfs) Pershing, Shelby, Woodlands along stream reaches, Kilwinning, Goss especially in the Chariton Hills area. 40c. Wooded Osage 3824 Unglaciated. Low cuestas and gentle 700-1100 Sandy clay, silty clay, and clay Mollisols (Argiaquolls, Sampsel, Polo, Snead, Mesic, 36-40 150-180 22-42; Little bluestem-sideoats grama prairie, Pasture, cropland, and areas of coal Plains undulating plains. / decomposition residuum. Alternating layers Argiudolls, Hapludolls, Hartwell, Kenoma, Thermic/ 68-92 big bluestem-Indiangrass prairie, mining. Winter wheat, soybeans, Intermittent and perennial streams, 75-150 of Pennsylvanian sandstone, limestone, and Argialbolls) Deepwater,Pershing, Udic cordgrass wet prairie,and oak corn, grain sorghum,other feed some channelized. shale. Alfisols (Epiaqualfs) Greenton, Dockery woodlands. grains, and hay are the major crops. Entisols (Udifluvents) 40d. Cherokee Plains 2509 Unglaciated. Smooth to irregular 700-1000 Clay and sandy decomposition residuum. Alfisols (Albaqualfs, Parsons, Barden, Dennis, Mesic, 38-40 150-180 24-45; Little bluestem-sideoats grama prairie, Pasture, cropland, and areas of coal 74. MISSISSIPPI VALLEY LOESS PLAINS plains. / Alternating layers of Pennsylvanian Hapludalfs) Hector, Bolivar, Mandeville, Thermic/ 68-92 big bluestem-Indiangrass prairie, and mining. Winter wheat, soybeans, Intermittent and perennial streams. 50-125 sandstone,limestone, and shale. Ultisols (Hapludults) Barco, Collinsville Udic cordgrass wet prairie. corn, grain sorghum,other feed Level IV Ecoregion Physiography Geology SoilClimate Potential Natural Vegetation Land Use and Land Cover Mollisols (Argiudolls, grains, and hay are the major crops. Temperature/ Precipitation Frost Free Mean Temperature Area Elevation/ Surficial material and bedrockOrder (Great Groups) Common Soil Series Moisture Mean annual Mean annual January min/max; Hapludolls) (square Local Relief Regimes (inches) (days) July min/max, ( F) Inceptisols (Dystrudepts) miles) (feet) ° 40e. Claypan Prairie 4129 Glaciated. Smooth plains. 700-1000 Loamy till and clay loam till. Well-developed Alfisols (Epiaqualfs, Mexico, Putnam, Leonard, Mesic/ 36-38 150-170 18-38; Big bluestem-Indiangrass prairie, little Cropland, pasture, and livestock 74a. Bluff Hills 357 Isolated low ridges. 300-500 Loess, cherty gravel and sand on ridges. Alfisols (Hapludalfs, Memphis, Loring,Falaya, Thermic/ 45-46 180-210 28-48; Post-blackjack oak woodland, southern Some woodland areas, pastureland, Perennial streams with many / claypan. Albaqualfs, Hapludalfs) Armstrong, Lindley Udic 66-90 bluestem-sideoats grama prairie, and production, especially hogs. Corn, Intermittent streams. / Alluvial sand, silt, and clay on terraces. Fragiudalfs, Albaqualfs) Adler, Zachary, Crowley Udic 68-92 red oak-white oak woodland, and and limited cropland of hay and channelized. 50-100 Pennsylvanian sandstone, limestone, and white oak dry woodland. soybeans, other feed grains, and hay 100-175 Bedrock exposures of Tertiary sands,gravels, Entisols (Fluvaquents, beech-maple woodland. forage crops. shale. for livestock are the major crops. and clays,Cretaceous sandstones, and Udifluvents) Ordovician dolomites.

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