The Prairie/Riparian boundary extends from Cold Spring Road, across Crooked Creek and along the wetland area, including the athletic fields and up to the border of the pond. The banks of Crooked Creek are lined with cement on both sides. The creek was apparently moved eastward prior to 1910, and the remnants formed the main pond that exists today.
A large portion of this area has been cut and filled with dirt from elsewhere. Marian University students took six soil samples from representative areas. Their pH ranged from 8.4 to 8.8. Each of these representative areas had different types of soil as well. These were loamy sand, sandy clay, sandy loam, clay, and sandy clay loam. The soils holding the most moisture were found next to the ponds and near the northwest side of the prairie boundary, as well as on the bank of the creek.
Crooked Creek starts in the southern part of Hamilton County and ends in Marion County in the White River, via Lake Sullivan. On its way to the White River, it flows through Pike, Washington, and Center townships in Marion County, and branches into Oil Creek, Payne Branch, Delaware Creek, and Ditch Creek. Crooked Creek is fed by 42 major storm sewer outfalls. The soil, as well as the abundance of tributaries, increases the flood potential of this area. The water quality of Crooked Creek is affected by the residential sewage runoff and other disturbances (like agriculture) upstream. The pH ranges from 6.49 to 7.12.
Most of the prairie/riparian area stays in full sun almost all day, with the edges of the area moderately shaded and fully shaded spots near the entrance to the EcoLab and the bridge over Crooked Creek on Cold Spring Road. The section east of Crooked Creek is also moderately shaded, as more trees are present there. None of this eastern section is in full sun for much of the day.
Turf grass was added to a portion of the area to construct what is now a softball field and practice soccer fields in the 60s and 70s. The prairie area near the ball field consists of weedy grass species such as the Fall Panicum (Panicum dichotomiflorum), Old Witch Grass (Panicum capillare), Yellow Foxtail (Setaria glauca), Giant Foxtail (Setaria faberi), Barnyard Grass (Echinochloa crus-galli), and Small Love Grass (Eragrostis pectinacea). The few woody plant species that line the creek are Cottonwood, Sycamore, and Rough-Leaved Dogwood. Other plants include Reed Canary Grass (Phalaris arundinacea) (which is not native to this area), False Sunflower (Heliopsis helianthoides), Autumn Sneezeweed (Helenium autumnale), and Canada Goldenrod (Solidago canadensis).
A December 2000 planting west of the softball field and adjacent to the wetland area included New England Aster, Purple Coneflower (Echinacea purpurea), Canada Wild Rye (Elymus canadensis), and Tall Coreopsis (Coreopsis tripteris). Some of the natives that have proven successful are New England Aster, Virginia Wild Rye (Elymus virginicus), Canada Wild Rye (Elymus canadensis), False Sunflower (Heliopsis helianthoides), and Blackeyed Susans.
Between the pond and the softball diamond (cut and fill area), there was an extensive prairie planting in June 2003. Here at least 29 species were introduced including Purple and Pale Purple Coneflower (Echinacea purpurea/ pallida), Tall Coreopsis, Rough Blazing Star (Liatris aspera), Mountain Mint (Pycnanthemum virginianum), Purple Prairie Clover (Petalostemum purpureum), and Yellow Coneflower (Ratibida pinnata). Some of the grasses introduced here in the same planting include Side Oat’s Grama (Bouteloua curtipendula), Canadian Wild Rye, and Virginia Wild Rye.
Plantings along the east and west sides Crooked Creek took place in April 2002 and followed the original Jens Jensen plan. Many of these were trees, such as ninebark, silky dogwood, washington hawthorne, elderberry, crabapple, river birch, and green ash. On the west side, 87 spicebush were also planted at this time. In June 2002, another planting occurred along the creek that consisted of crabapples and river birch again, as well as various grasses: Silky Wild Rye (Elymus villosus), Virginia Wild Rye, Bottlebrush Grass. Many wildflowers such as New England Aster, Blackeyed Susans, and False Sunflower were also planted here, along with Foxglove Beardtongue (Penstemon digitalis), Wild Golden Glow (Rudbeckia laciniata), and Stiff Goldenrod (Solidago rigida).
However, reintroducing species has proven to be challenging in the tall grass prairie plot, as plantings of White Vervain and Indian Grass in the prairie area have not faired well against the seed bank (found already in the soil) apparently full of Canada Goldenrod. Despite recent plantings of natives in this zone, there are still several invasive non-natives and aggressive natives. Some of these non-natives are not threatening, like the Indian Strawberry (Duchesnea indica), the White Campion (Lychnis alba), and Velvet Leaf (Abutilon theophrasati). Many, however, are invasive: Japanese Honeysuckle (Lonicera japonica), White Sweet Clover (Melilotus alba), English Plantain (Plantago lanceolata), Yellow Sweet Clover (Melilotus officninalis), and Wintercreeper (Euonymus fortunei). Still others may not necessarily be invasive or non-native, but often appear in disrupted habitats: Spiny Sow Thistle (Sonchus apser), Nightshade (Solanum americanum), and Yellow Foxtail (Setaria vbiridis).