Professor Greens Buildings With Lichens

By Dees Stribling, Contributing Editor

New York—There are many ways that a large building, including a multifamily structure, can go green. A Rutgers-Camden professor is at work on a new way to green buildings—both figuratively and quite literally—that involves lichen.

Elizabeth Demaray, an associate professor of fine arts at Rutgers-Camden, is currently cultivating lichen on the sides of New York City skyscrapers to, as she puts it, counteract the lack of native vegetation found in the city. Her “Lichen for Skyscrapers Project” was featured as part of New York’s Art in Odd Places Festival from Oct. 1-10 and is now on view as a site-specific installation in Manhattan on 14th Street between Union Square Park and the Hudson River.

It’s been well established that large urban centers affect local air temperatures, a phenomenon sometimes referred to as “urban heat islands” because urban areas create heat and trap heat. A large part of this process is due to the materials used to built cities, along with architecture of the buildings themselves.

According to Demaray, one of the ways to reduce heat in cities is to cultivate lichen on buildings, which can lower cumulative temperatures by absorbing sunlight and reflecting heat due to its light color palate, while making oxygen and creating green space on the sides of buildings. As a combination of fungi and algae, lichen does not have roots and grows vertically on porous surfaces. It thrives at high altitudes, where it can withstand periods of drought by absorbing water out of the air.

But how to cultivate lichen on buildings to achieve the desired environmental affect, while looking good at the same time? Demaray “plants” the lichen by painting a lichen slurry, a watery mixture, on the sides of the buildings in patterned, geometric shapes. These plantings allow viewers to watch the organic lines of the lichen slowly outgrow the manmade lines of the patterns. If the lichen doesn’t take, it will simply dry up and blow away.

For the Art in Odd Places Festival, Demaray planted small plots of lichen slurry and also installed mature lichen-covered plaques with the permission of several buildings in New York City. Once the slurry is spread into place, it takes about three months for the lichen to propagate.

Demaray says that “there’s no reason lichen can’t be cultivated on large multifamily buildings” (with permission, of course). “Liken likes all sorts of porous surfaces,” she tells MHN.

“I originally created the Lichen for Skyscrapers Project because people in highrises have such a limited connection with the natural world, and it occurred to me that even if you could only open your window a few inches, you could still apply a lichen slurry to your window ledge,” she continues. “But really, in my opinion, any manmade structure could ecologically benefit from a lichen planting.”