**300 copies** Plein Air the album presents recordings from a plant-driven synthesizer. A custom built instrument that uses scientific sensors and software programming to generate real-time tree leaf data. Light, photosynthesis and transpiration modifies sound: the rhythm, melody, texture, tempo and harmony shift with atmospheric conditions and tree response – electronically. The sounds of each leaf of regional deciduous trees by scientifically sensored data-sonification are much more musical than one could imagine. Their timbre and volume always depend on light and temperature, number of audience. It varies from site to site and from country to country. We can hear loops of rhythmic sequences, groups of tiny computer generated signals, long drones which change constantly and are hard to describe. Side 1 includes four short recordings, in total twenty-six minutes, of one leaf from Scottish Elder, Oak, Elderberry and Birch, recorded in one of Glasgow’s historical green houses, June 2017. Due to dramatic light and temperature changes that occur as sunshine and cloud formation changes in proximity to the north Atlantic; the computer generated music is highly dynamic, an intense hearing experience at times as I would imagine a tornado. Side 2, is one recording, in total twenty-five minutes, of a regional heritage pear tree leaf that sounds more like Minimal Music. During the Cologne Tree Sound Study, we made the recording in a small office room in 2015, we had less dramatic weather changes. A warm summer, smooth light changes, generating a more gentle soundscape to deeply plunge into music. - Georg Dietzler

Plein Air the album is based on a ten-year artist-led project. In simplest terms our intention is to provide a ‘mind / body experience’ of trees by attending to the sound of physiological reaction (photosynthesis and transpiration) as one leaf adjusts to the day to day changes (rush hour traffic, crowds of people) in ground level atmospheric chemistry in venues and cities. Physiological data is transposed into sound through computer software. We have chosen sound for its aesthetic purity with the goal to hear the trees more clearly as they react to changes in CO2, temperature and humidity. This system is called ‘Plein Air’, a stable single platform system that embraces the portable easel, as a metaphor for the historic practice of open air painting. Where Millet extended the idea of landscape to peasants working in the fields and the impressionists examined the phenomenological exchange between light and material. At the same time, recent work with the system raises questions about what we expect to ‘hear’ when we listen to nature, as it reacts to intense inputs of carbon dioxide? - Tim Collins