Peter Del Tredici, senior research scientist at Arnold
Arboretum and a lecturer at the Harvard Graduate School of Design, makes an
excellent case for urban ecologies. In his article, Flora of the Future, in
Places journal (April 2014, available at https://placesjournal.org/article/the-flora-of-the-future/?gclid=COrKpNWPo88CFdcWgQod1UkAEA),
Del Tredici emphasizes two ecological tenets: that environmental stability
is an illusion, and that an unpredictable future belongs to the best adapted.
Hence, the dynamics of urban plants. Peter also points out some fun “new
infrastructural taxonomies” that include:
· The
chain link fence. “They provide plants — especially vines — with a convenient
trellis to spread out on and a measure of protection from the predation of
maintenance crews.”
· Vacant
lots. “Their soils typically have high pH levels, and they are usually
colonized by a suite of plants that I like to refer to as a “cosmopolitan urban
meadow.”
· The
road median strip. “In short, the median strip is perfect for crabgrass.”
· Stone
and masonry walls. “From the plant’s perspective, these structures are
good stand-ins for a limestone cliff, and many cliff species are well adapted
to growing on city walls. “
· Pavement
cracks. “We tend to think of pavement cracks as stressful habitats, but in
fact, as the water sheets off the pavement, it flows right into the crack,
making it a rich site in terms of its ability to accumulate moisture and
nutrients”
· Specialized
microclimates. “As an example, carpetweed (Mollugo verticillata), a summer
annual from Central America, subsists only on air-conditioner drip.”
· River corridors. “They
serve as important pathways for the migration of both plants and animals into
and out of the city.”
These are fun to think about, what are some other spaces
unique to the urban fabric that create their own micro-ecologies—drainage
swales, brick walls, flat roofs, parking lots, steps, utility rights-of-way,
etc. How many species can we find?
