The Natural Areas of the Palos Park-Orland Park Area

Originally the open lands of Palos-Orland area were a composite of sloughs, peat bogs, creeks and wetlands, prairies, savannas and oak-hickory forests. These natural areas all developed on the rolling and young topography of the Valparaiso ground Moraine, a set of Post-Pleistocene glacial features about 15,000 years old. The northern edge of Palos Park is marked by two terminal moraines–the Tinley and Valparaiso. The terminal moraine area of Palos Park is characterized by kames, eskers, glacial potholes, ravines, and unconsolidated deposits of clay and sand from earlier glacial periods. All these features contribute dramatically to the vistas, natural beauty, and interesting plant communities found here. In addition, Orland Park lies on the continental divide of the US, separating the Mississippi watershed from the Great Lakes/Atlantic drainage system. Indeed the combination of a good regional location, the Wabash RR line route, and natural features all contributed to the economic success of early farming, peat mining, and later suburban settlement with retail development.

The history of development of the Palos-Orland area initially relied upon its natural features. The continuing quality of life in here depends upon preserving many of the natural features that attracted us to settle here in the first place. These natural areas are disappearing very quickly and few may be left by the start of the next century. The following natural areas are the primary natural community types found here. Many of these natural areas are fire adapted. Saving these areas will preserve open space for us now and for our children.

Oak-Hickory Forests

These closed-canopy forests occur on the most well-drained slopes and hilltops. The dominant trees are White Oak and Shagbark Hickory with some Sugar Maple. The best forests are already preserved in the Palos forest preserves. However significant other forests still remain in the northwestern, southwestern and west central parts of the Orland Park. These forests contain a rich spring flora understory and could form a greenbelt linking Orland Park with forest systems elsewhere in Will and Cook County.

Savannas

These forests are dominated by Bur Oak and White Oak with a grassy understory. These communities are maintained by periodic fires. The soils are transitional between prairie and forest. The forest preserves in Palos-Orland were once mostly savanna, especially south of 127^th Street. Humphrey Woods is part savanna and part Oak-Hickory forest. A few very rare plants are found in this habitat such as the Savanna Blazing Star. Very little of this plant community remains in Orland Park and what does is located in northern end of the Village.

Prairies

This community is the rarest in Orland Park and Palos Park. Almost none remains (just a little on the edges of forest preserves and railroad embankments). The prairies originally contained tall perennial grasses and forbs (wildflowers) dominated by Big Blue Stem, Indian Grass, Porcupine Grass and Little Blue Stem. Fire is also an important management tool for prairies. The original prairie soils were rich black clay loams and formed the basis for agriculture here.

Wetlands, Creeks & Ponds

These are the most diverse communities here. Many wetland and aquatic community types occur in Palos-Orland: peat bogs (which still exist at the Southmoor site), cattail marshes, sedge meadows, swamps, sloughs, vernal ponds, headwater wetlands as well as creeks and streams. Many contain rare sedges and unusual aquatic plants. These communities support an abundance of wildlife (many which are state threatened or endangered) and perform important functions in reducing flooding and cleansing area runoff. Orland Park sits on a true continental divide with Mill, Tinley, & Midlothian Creeks flowing into Lake Michigan while Marley, Long Run, and Spring Creeks flow into the DesPlaines River. Palos Park lies almost entirely within the Mill Creek watershed.