4. Southern Till Plains

5. Southern Till Plains
This division is composed of dissected Illinoian glacial till south of the Shelbyville Moraine and the Sangamon River and Macoupin Creek watersheds. Both forest and prairie were present at time of settlement. Soils are relatively poor due to clay content and frequent claypan subsoil. Post oak flatwood forest is typical of the division.

6. Southern Till Plains
Forest – poorly drained heavy upland soils support mostly flatwoods forest of post oak, swamp white oak, blackjack oak, and pin oak. Forests on the uplands with better drainage support black oak, shingle oak, mockernut hickory, and shagbark hickory mixed in with post oak. Forests on slopes above stream valleys are dominated by white oak, shingle oak, and black oak on drier southern and northern exposures. And hickories, white ash, basswood, sugar maple, wild black cherry, slippery elm, and black walnut among oaks are common in wetter slopes.
Floodplain forests are dominated by silver maples, willows, sycamores and American elms near the Mississippi River with pin oak, white oak, hickory, ashes, hackberry, and honey locust farther from the river.

7. Southern Till Plains
Prairie – accounted for about 40 % of uplands – most was mesic tall-grass prairie similar to that in the Grand Prairie Division. Alkaline slicks may have supported a unique vegetation but this is not well understood.
Marshes are found along the stream floodplains – cattail, bulrush, etc.

8. Post Oak – Southern Till Plains

9. Shingle Oak – Southern Till Plains

11. Wabash River Bottoms

12. Wabash River Bottoms
This division includes the bottomlands of the Wabash River and its major tributaries, the loess covered uplands bordering the Wabash River, and the forests of the Vermilion River, Little Vermilion, and Crab Apple Creek. This is a region of lowland oak forests containing beech, tulip tree and other trees typical of the forests to the east of Illinois. Wabash River drainage contains several distinctive fishes.

13. Wabash River Bottoms
Forests – Bottomland forests – pin oak, overcup oak, swamp white oak, swamp chestnut oak, bur oak, cherrybark oak, and Shumard oak. Often associated with the oaks are sweetgum, hackberry, American elm, kingnut hickory, silver maple, and pecan. Best drained terraces also have shagbark hickory, tulip tree, kingnut hickory, and Kentucky coffee tree. Along rivers are found black willows, cottonwood, sycamore, and silver maple. Sloughs support bald cypress and some other southern swamp species.
Mesic uplands support white oak, red oak, and sugar maple with some beech and tulip tree. Dry uplands have black oak and hickories.

14. Wabash River Bottoms
Prairies – some mesic prairies in uplands, bottomlands support mesic and wet prairies – all similar to those of the Grand Prairie.
Marshes – large areas of marsh dominated by cord grass and river bulrush

15. Sweet Gum – Wabash River Bottoms

16. River Bulrush – Wabash Border Division

18. Illinois Ozarks

19. Illinois Ozarks
This division consists of the part of the Salem Plateau of the Ozark Uplift located in Illinois – mostly from Northern Monroe County southward into the glaciated sandstone ravines in Randolph County. It has many species typical of the Ozarks, south and southwest.

20. Illinois Ozarks
Forest – Almost entirely forested at time of settlement. Northern forests consist of red oak, sugar maple, basswood, and Ohio buckeye on mesic sites and white oak, black oak, and hickories on ridge tops. Beech and tuliptrees occur in the mesic forests of the central section. Forests of the southern section contain many tree species including cucumber tree, blackgum, butternut, black walnut, bitternut hickory, in addition to red oak, sugar maple, basswood, white oak, black oak, Ohio buckeye, beech and tuliptree. Yellow-wood occurs in limited areas in southern section. Some shortleaf pine in the south.

21. Illinois Ozarks
Prairie – loess hill prairies are found on top of the river bluffs. Similar to the loess hill prairies of the Middle Mississippi Border Division with little bluestem and sideoats grama dominating.

22. Ohio Buckeye – Ozark Division

23. Blackgum – Ozark Division

25. Lower Mississippi Bottomland Forests

26. Lower Mississippi Bottomland Forests
This division includes areas near the Mississippi River and its floodplain from Alton to the Thebes Gorge. Mississippi is very muddy here due to silt load from the Missouri. Northern part had prairie, marsh and forest. Southern part was densely forested.

27. Lower Mississippi Bottomland Forests
Forests – Northern section mostly forested at time of settlement. Light soils supported silver maple, ashes, American elm, honey locust, sugarberry, and pecan. Beech, basswood, and red buckeye also found on loamy soils. Southern section bottomland forests supported pin oak, overcup oak, Shumard oak, cherrybark oak, along with kingnut hickory, sugarberry, and sweetgum. Swamps supported pumpkin ash, swamp cottonwood, Drummond’s red maple, and water locust. Bald cypress occur as far north as Union County.

28. Lower Mississippi Bottomland Forests
Prairie – relatively large areas of wet and mesic prairie in the northern section but most have been drained for agriculture. They were similar to wet and mesic prairies of the Grand Prairie.
Marsh – northern section had large marshes dominated by river bulrush, cattail, lotus, and pickerelweed. Some marshes remain.

29. Overcup Oak – Bottomland Forests

30. Pickerelweed – Lower Mississippi River Bottomlands

32. Shawnee Hills

33. Shawnee Hills
The Shawnee Hills extend across the southern tip of the state from Fountain Bluff on the Mississippi River to the Shawneetown Hills near the mouth of the Wabash River. This unglaciated hill country is characterized by a high east-west escarpment of sandstone cliffs forming the Greater Shawnee Hills and a series of lower hills underlain by limestone and sandstone known as the Lesser Shawnee Hills. This was mostly forested and much of that forest remains today. Many distinctive plants are restricted to this division of Illinois.

34. Shawnee Hills
Forests – Much timber is still present. Upland forests are dominated by white oak, black oak, and shagbark hickory with post oak, blackjack oak, scarlet oak, and pignut hickory on dry sites. Deep mesic ravines have red oak, beech, tuliptree, bitternut hickory, sugar maple, and white ash, with some black walnut, butternut, Ohio buckeye, and basswood.
Floodplain forests also contain sycamore, Kentucky coffeetree, sugar berry, and honey locust.

35. Shawnee Hills
Prairie – Limestone glades in lesser Shawnee Hills support dry prairie like those of hill prairies in western Illinois but with addition of southern plants like wild blue sage and heart-leaved tragia.

36. Shawnee Hills
Distinctive plants – filmy fern, Virginia saxifrage, small-flowered rock-pink, thread-leaved evening primrose, synandra, French’s shooting star, and small-flowered alumroot.

37. Shawnee Hills

39. Shawnee Hills – Limestone Glade

40. Limestone Glade
Glades differ from hill prairies in having exposed bedrock which is usually limestone but may be sandstone. They often support a variety of mosses and lichens. Western succulents like prickly pear and sedum are common. In the spring there can be showy displays of purple coneflower, New Jersey Tea, and wild hyacinth. Blackjack oak and red cedar may be common. Unusual animals present include the lichen grasshopper and olive hairstreak butterfly.

41. Tulip Tree – Shawnee Hills

42. Thread-leaved Evening Primrose - Shawnee Hills

44. Coastal Plain at Cairo

45. Coastal Plain Division
This is a region of swampy forested bottomlands and low clay and gravel hills that is the northernmost extension of the Gulf Coastal Plain Province in North America. Bald cypress-tupelo gum swamps are unique in Illinois and many southern animals and plants are found here. It has a relatively mild climate and is the warmest region in the state.

46. Coastal Plain Division
Forest – Mostly forested prior to settlement. Upland forests like those of Shawnee Hills – mostly black oak, white oak, red oak, cherrybark oak, blackgum, tulip tree, shagbark hickory, and pignut hickory, also some beech, cucumber tree, and native chestnuts.
Bottomland forests – Shumard oak, cherrybark oak, swamp white oak, swamp chestnut oak, pin oak, overcup oak, kingnut hickory, shagbark hickory, bitternut hickory, ashes, sweetgum, blackgum, honey locust, sugarberry, pecan, wild black cherry, and catalpa. Silver maple and American elm grow along streams.

47. Coastal Plain Division
Bottomland swamps – bald cypress, tupelo gum, swamp cottonwood, Drummond’s red maple, water locust, pumpkin ash, and overcup oak. Some water hickory and planer-tree too.

48. Coastal Plain Division
Prairies – some prairies occurred on dry and mesic upland hills. Dry prairies were dominated by little bluestem. Mesic prairies were dominated by big bluestem, Indian grass, and grama grass.
Southern seep spring bog – Some seep springs in the eastern hills are very acidic and support sedges, royal fern, lady fern, and cinnamon fern. May contain large areas of sphagnum moss. Have many southeastern species like netted chain fern, screw-stem, and incomperta sedge.

49. Bald Cypress – Coastal Plain Division

50. Netted Chain Fern – Coastal Plain Division