Thursday, September 22, 2016

Flora of the Now



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?


Thursday, September 1, 2016

What nature will be like?

“Because life is fueled by the energy captured from the sun by plants, it will be the plants that we use in our gardens that determine what nature will be like 10, 20, and 50 years from now.”
 -- Doug Tallamy