City Trees

Blake Shepard designed the Palm Reflections xplainer video to both welcome people and set a tone with a throwback to early computer graphics. He says, "In this exhibit about the intersection of technology and nature, I wanted the video to elicit the sense of wonder from the early stages of computer graphics; it's an on-the- nose style to represent this new frontier that's emerging between technology and communion with nature." The intention of the Festival is to celebrate the beauty of the Gardens by emphasizing the plants and landscape in artistic ways. This event seemed like a perfect opportunity and setting for Moore to manifest his long-held dream of creating a soothing and peaceful public sound installation generated by plants. When he contacted event organizer Tora Rocha in August of 2021 with his proposal, she was delighted that the City's urban forester took creative interest in the Gardens and welcomed him as a contrib- utor. To live up to the visual focus of the event, Moore envisioned having the plants control not only sounds, but also lights. This seemed technically possible, but far beyond the frontier of how PlantWave is commonly used. Moore immediately contacted Shepard to be a collab- orator, knowing that his friend's enthusiasm, creativity, artistic and technical skills, and legitimacy as a licensed therapist would make him a perfect fit to manifest an impressive and meaningful installation. The duo had just over two months to figure it all out—at the outset, they had only a small fraction of the equipment needed for the gig. Ongoing innovations and problem-solving leading up to the event led to a breakthrough success. In simple terms, how does this technology work? PlantWave functions the same way as a lie detector, by measuring the electrical conductivity of an organ- ism's surface. Lie detectors measure the presence of sweat on skin, whereas with PlantWave, two electrodes are attached to plant leaves and measure the electrical conductivity between the two points. This conduc- tivity is a function of the amount of water that the plant cells are moving around from moment to moment. Thus, as mediated through PlantWave, the greater the fluctuation between two musical notes, the greater the physiological change that is happening within the plant. In essence, the internal processes of the plant that are invisible to the naked eye are responsible for gener- ating sound. This may include photosynthesis or other processes, and it's apparent that the sounds change depending on which plant you connect to and whether it's day or night—along with a host of other environmental conditions. These fluctuations inspire a lot of curiosity as to what exactly is going on inside the plant, leading to many questions and possibilities for research. >> Photos of lit fronds by Jason Favreau urban-forestry.com 33

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