The low, periodically wet zone in front of the museum was planted with tree and shrub species that normally occur in streamside sites: red maple, musclewood, swamp azaleas, elderberry and strawberry bush. The ‘river of space’ in the middle of this zone was planted with river oats; it is bordered by a sequence of moisture-loving perennials, for example ragwort (Senecia aureus), cardinal flower (Lobelia cardinalis) and large, exuberant autumn-blooming Joe Pyeweed (Eupatorium maculatum), ironweed (Veronica spp.), sunflower (Helianthus spp.) and goldenrod (Solidago spp.) (Figures 5.7 to 5.9).
‘Granite outcrop’ circular garden
In the hot, exposed circle in the centre of the granite-paved entrance courtyard is the symbolic centrepiece of the native community plantings: a stylised version of a granite outcrop, utilising locally quarried granite and plant species from that environment (Figures 5.10 and 5.11). The design incorporates an ephemeral pool in a spiral form, a Georgia oak (Quercus georgiana) as the single, sculptural tree, and a variety of lichens, mosses and both annual and perennial herbaceous plants grow in crevices and openings between the flat granite stones that cover much of the circular area. The concrete – bottomed pool, lined with a layer of granite sand, varies in depth, grading from very shallow on the inside edge of the spiral to approximately 18 inches at the outer edge. The smooth line of the pool edge is interrupted once, with a lichen-covered boulder that slightly overhangs the outer edge of the pool. Rainfall provides water for the pool; its level fluctuates with rainfall patterns, and it is even permitted to dry out during dry periods.
Museum of History, Atlanta History Center, Georgia, with granite outcrop garden (autumn 1993)
Detail of a portion of granite outcrop garden, Atlanta History Center (winter 1994)
Because the plants of this community have adapted to extreme heat and drought, no supplementary water is supplied to them. Growth, re-seeding and vegetative spreading of characteristic granite outcrop vegetation will be permitted to occur, with the only management being the removal of non-indigenous species, and an early spring clipping of the previous year’s herbaceous foliage.
In summary, the design of the approximately two acre landscape surrounding the Atlanta Museum of History was based on different Piedmont plant communities or successional stages, but with some level of stylisation, both in plant selection (drawing on ‘visual essence’ species) and in placement (forming perceptible masses and swaths of distinctive native species). The granite outcrop garden, particularly, is a symbolic representation: a sculptural composition designed to fit into a circular form, but one which expresses the essence of a unique and regionally significant natural community. Throughout the different community representations, the goal of sustainability is approached, with management inputs mainly limited to the removal and/or suppression of exotic species, once the initial plantings are established.
Whilst the use of native vegetation and natural dynamics in designed gardens and landscapes in American landscape architecture during the last quarter-century is increasing, it remains an undercurrent, rather than a mainstream activity. There is sometimes a misperception that designing with native plant communities and natural processes in not sufficiently artful. In reality, it can be considered to be a new art form appropriate to the twenty-first century: ‘ecological art’, which is simultaneously aesthetically rich, ecologically sound, evocative of place and dynamic.