Chicago’s 606

Planting plans

606 Trail Chicago, IL © Adam Alexander Photography 2015

Unlike other elevated rail parks built on bridge platforms, The 606 is supported by massive concrete retaining walls filled with lake sand, silt, and gravel. The design calls attention to this original construction by lowering the path and exposing the sides of the retaining walls. Manipulating topography also facilitates access to the elevated landscape, helps slow cyclists down, accentuates views and increases ecological variety – creating a succession of shaded, wet, and enclosed environments in the low points, followed by dry, exposed highpoints with stunning views, as the line crosses major city boulevards or streets.

A two-lane bike path (with one lane in each direction) runs atop the entire length of The 606, flanked by rubber track jogging paths on each side. The paths take up about half of The 606’s 30-foot width, leaving the rest for landscape design, seating, low key meandering footpaths and art installations.

One such installation is the Environmental Sentinel, a trail-wide flowering spectacle and sculpture that highlights the unique environment created by Lake Michigan and the impacts of climate changes.

Frances Whitehead drew inspiration from Japan’s Cherry Blossom Festivals, which has been celebrated in Kyoto and the surrounding towns since the 8th century. The people of Japan began keeping records to document the bloom times of cherry trees every year in order to know when to schedule cherry blossom celebrations. Japan’s cherry blossom monitoring and record keeping is now the longest running phenological data set available that documents a changing climate.

As The 606 runs perpendicular to Lake Michigan, the climate becomes slightly cooler as one gets closer to the lake. Cloned service berry trees (the Amelanchier x grandiflora ‘Autumn Brilliance’ spp., a native to the area) and the Chinese lilacs (Syringa x chinensis ‘Red Rothomagensis’ spp., a non-native plant) are dotted along the park, bursting in bloom every spring but with a delay of up to five days between the east and west end of the trail. Chinese lilacs are used by the USA National Phenological Network as the calibrating plant for comparing observations across geographies and plant families, and extend a “legacy” data set dating back to the 1970’s. This Environmental Sentinel also provides the basis for a citizen science project monitoring blooming time every year and on-going climate changes. Interpretative signage is built-in into the concrete wall and surfaces of the park to help engage trail users with the project. This includes “compass roses”, displaying the North arrow pointing East, towards the lake, as a clue to the reorientation needed to understand the impacts of the local micro-climate and of climate changes.  Mile markers are also set in the jogging path near specific trees fitted with barcodes, making it easier to locate and return to any given specimen for monitoring. Further details on this, and other citizen science projects and research partnership supported by The 606 can be found here.

The wider planting scheme is akin to musical score, combining “key themes” and “variations”. Some of the key themes include the use of evergreens at entrances and the abundance of sedges throughout the park, reminiscent of the North American Midwest’s native prairie landscapes. By contrast, distinctive planting events such as the Poplar Thicket, the Sumac Tunnel, or the Echinacea Field work in concert with changes in topography, microclimate, and spatial enclosure to create variety along the length of The 606. More details about the plant palette used and the way in which it was deployed can be found here and here.