Parks and Recreation System Master Plan Update (2016) parks_and_recreation_system_master_plan_update_oct | Page 453

Airport, I-65 corridor, the Watterson Expressway, and much residential
development. Historically, this area was an epicenter for industrial and
manufacturing development, as well as suburban growth. The Slack Water Flats is
dominated by poorly drained clay soils and its historic name was "Wet Woods", a
relic of the area being an ancient lakebed. There are several tracts of relatively
high quality bottomland hardwood wetlands in this physiographic region,
including 80 acres at the Trinity site (and environmental easement is held by the
Louisville and Jefferson County Environmental Trust on the Trinity property) and
another 80 acres in the Mae Sawyer/KYTC tract.
The Knobs physiographic region is an area of significant topographic
relief compared to the surrounding ecosystems. The Knobs region, which can
range from approximately 500 to 900 feet i n elevation, is a dynamic ecosystem.
Soil type, slope, and aspect are all significant variables in the determination of
ecoregions. The Jefferson Memorial Forest is almost entirely in the Knobs region
and possesses shale, limestone, and sandstone soils. Due to the diverse soils,
Jefferson Memorial Forest likely contains oak savannahs, sandstone glades,
limestone slope glades, as well as the western mesophytic forest. According to the
Kentucky State Nature Preserves Commission, the Spiranthes ochroleuca or
Yellow Nodding Ladies’-tresses, is a rare flower (G4; S2) that would have
historically occurred in the southern part of the Jefferson Memorial Forest,
especially along the border of Bullitt County.
The Ohio River Valley physiographic region contains two distinct
ecoregions: alluvial floodplain riparian forest and xerohydric flatwoods. The
alluvial floodplain riparian forest contains forest and grassland species,
particularly Black Willow, River Birch, Sweetgum, Pin Oak, as well as Eel-grass
found in the adjoining Ohio River. Caperton Swamp and Portland Wharf are two
prime examples of this terrestrial ecological community. Xerohydric flatwood is a
lowland terrestrial ecosystem that is dry in the summer, with clay hardpan soils,
and wet in the winter. Sweetgum and River Maple are common in this ecosystem,
as well as many types of orchids, the Ozark Trillium (Trillium ozarkanum), and
the Southern Twayblade (Listera australis). The Community Improvement
District (CID) land in southwestern Jefferson County and Riverside, Farnsley-
Moremen Landing are excellent examples of a xerohydric flatwood. Originally set
aside for flood water control, CID land has been left unmanaged for the past
couple of decades, but still has significant areas of disturbance from illegal
dumping, ATV use, hunting, old buildings and structures, and runoff from nearby
roads and highways.
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