CASE STUDY
14 January/February 2016 Landscape and Irrigation www.landscapeirrigation.com
PROJECT FRUITION
Motherplants brought in 3,000 plugs in November 2012, the
earliest the roof could be readied for planting. Mark Winterer,
co-owner of Recover Green Roofs, who collaborated on the
planting, said, "We had to wait for the ground to thaw every
morning before we could plant." However, planting the plugs in a
dormant state turned out to have an advantage — their moisture
requirements were low; and with supplemental water provided
for just the first few weeks after planting, the vast majority of the
plants came through the winter and established well.
A highly porous, lightweight growing medium was conveyed
to the site by a blower truck; it was intended to have less than
10 percent by mass organic matter (OM), because overly fertile
soil would preference the growth of certain species over others,
which would have upset the plant-community balance the
designers sought. (Based on observing overly vigorous growth of
some plants, Leopold later commented that 5 percent or less OM
would have worked better.)
The earth was sculpted with sections of expanded polystyrene
geofoam to provide some undulations for aesthetic and
microclimate purposes. Jute erosion control mat, while difficult
to install on a windy rooftop in November, turned out to be
extremely important in stabilizing the friable growing medium
against erosion. Irregular flagstone slabs mimicked the limestone
and pavement found in the Alvar environment, and provided
entry points for teachers and students to gain a closer look at the
plants. In terms of the planting, Toland said, "The patterning of
the species was based on massing for aesthetic impact and to aid
in monitoring."
Three-plus years after installation, the green roof plant
communities are thriving, and the beautiful outdoor gathering,
teaching, and research space is fulfilling its mission. Leopold said,
"Given that we are not aware of any similar planting on any other
green roof in the U.S., I have been very pleased that the plant
species that we selected have generally thrived under these very
challenging growing conditions."
Hydrologic monitoring has been conducted by SUNY ESF
Associate Professor of Environmental Resources Engineering
Doug Daley and others to document that the green roof fulfills
its stormwater management objectives as well.
SUNY ESF and Andropogon Associates received the 2014
Merit Award from the New York Chapter of the American Society
of Landscape Architects for the Gateway Center Green Roof. The
green roof is open to the public during regular business hours,
and is not to be missed if you find yourself in the vicinity of
Syracuse, N.Y.
Michelle Sutton (michellejudysutton.com) is a horticulturist,
writer, and editor.
Left: The SUNY ESF Gateway Center Green Roof was designed to be used extensively for teaching about native plants and native plant communities, soil
hydrology, entomology and more. Photo by Michelle Sutton Right: Gateway Center Green Roof in July. Photo by Michelle Sutton
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