Shades Creek rises fourteen miles above Jemison Park, from springs in the woodlands northeast of Norris Yards at an elevation slightly more than 800 feet above sea level. Below Jemison Park, the creek continues southwest for another 43 miles until, in Shelby County near the Bibb County line, it enters the Cahaba River; there the elevation is about 310 feet. Shades Creek and its tributaries drain the 135 square miles between the ridges of Red Mountain and Shades Mountain.
The largest tributary in the upper reaches of Shades Creek is Watkins Brook, which empties into Shades Creek at the southwestern end of the park, a few yards above the Cahaba Road bridge. At the bridge, the elevation of the creek bed is 635 feet, and the surface drainage from more than fifteen square miles flows through this point.
Imagine a moderately heavy rainfall – three inches overnight – in late March. Since the preceding September, when in many places the creek was only one or two inches deep, the water has steadily risen and is now less than a foot from the top of the banks in the park. The winter rains – there are approximately 45 significant rainfalls between the first of December and the end of March – have already saturated the ground. After the January and February freezes, there are comparatively few leaves and little plant growth to absorb much of the rain. The days in late March are still relatively short, the skies probably cloudy, and there has been little evaporation of the ground moisture.
The three-inch rain dumps more than a half-million cubic feet of water into the area that must drain through Jemison Park. Much of the rain water enters Shades Creek within an hour. The flow of the creek speeds up to let more water pass. The amount of the water, however, is too great, and the water goes over the creek banks and onto the flood plain.
All of Jemison Park – except the high land along Overbrook Road and along parts of Watkins Brook – is floodplain. This, and the existence of the creek itself, are the most important facts in the life of the park. Several times a year, much of the park is covered with water from the swollen creek, often for several hours.
These annual floodings mean that plants which cannot tolerate much water – such as hepatica, dwarf iris, and trillium, which live in abundance a few hundred feet away on the northern slopes of Shades Mountain – can generally be seen in the park only along the Nature Trail below Overbrook Road. Other plants which thrive with plenty of ground water – such as white buckeye, paw-paw, sweetshrub, and golden ragwort – can be seen in great abundance in the park along Mountain Brook Parkway.
Some of the plants that need constant water – jewelweed, cardinal flower, elderberry, and cane – live along the stream bank and in low spots. The drastic seasonal variations in the depth of the water, however, do not permit much typical marsh growth.
The most dramatic recent growth has been the privet, a plant which came to this country from southern Asia and did not exist to any extent in the park as late as 1925. Today, privet and honeysuckle, also introduced from the Orient, are covering much of the park land that might otherwise host native plants.
The park trees, a mixture of pines and hardwoods, are second growth. Before 1900 this land had been cut over to provide land for farming and fuel for the McElwain iron furnace. Today in the park the heavy tree cover blocks much of the sunlight. The softwoods have difficulty regenerating. However, older specimens of loblolly and shortleaf pines can be seen throughout the park. Occasionally, when some of the older trees fall, windows to the sun are opened, and the pines spring up.
The great amount of tree shade means that many of the park’s smaller shrubs and the wildflowers must not require much sunlight. The combination of shade and moisture also attracts ferns, such as cinnamon, lady and New York; the park has at least ten fern species.
The most dramatic recent physical changes in the park have been the addition of the trail system, the clearing of much of the undergrowth, and the planting of grass in some areas.
All of these factors determine what kinds of animal life can survive here. The most numerous of the larger mammals in the park – the raccoon – nests in holes in the dead hardwood, and sometimes pine trees. These dead trees are also the home of the pileated woodpecker. The undercover provides nesting space for cardinals, towhees, Carolina wrens, brown thrashers and many other birds. The moist ground below is a home for many species of amphibia.
The challenge to the life of the park today is people and the way people deal with the park. Friends of Jemison Park hopes you will join in trying to conserve our park.
— Thomas N. Carruthers
Additions to the Park
In 1976, Susan L. and Carter S. Kennedy generously contributed five acres of land between Easy Street and Shades Creek to the Friends, and in 2000 Frances B. and James W. Shepherd donated a crucial piece of land on the south side of the creek along Overbrook Road that includes part of the Nature Trail.
During the early years of the Friends, Luke Evins offered to donate to the City of Mountain Brook a parcel of streamside land on the south side of Shades Creek upstream from the Mountain Brook Club golf course and adjacent to the Civil War foundry. Since the City declined the offer at that time, the Friends of Jemison Park accepted it as a valuable piece of park land within the city limits. It was later given by the Friends to the City and has become an important and scenic link in the Mountain Brook Trail System.