Provoked by questions surrounding the nature of sound in/through/among trees, we completed our first auditory exploration on tree C7 in the allee. Carefully working through the layers of bark until we encountered the living matter of the tree, we carved a 4 inch square hollow in which to place our listening device. This device is an ElectroVoice Model 805 Crystal Contact Microphone, circa 1950 (incidentally and coincidentally,this exact model of microphone has apparently been used on trees before to record beetle movement!).
The first tests frame the tree as a resonator, planting the microphone within the hollow and recording the output with a zoom mic. Using a mallet on the bark we circumscribed the tree with a series of taps moving first away from the mic and returning to it from the other side. This exercise produces a few new ways in which to draw/diagram the tree. The recorded audio itself (with some simple noise reduction applied) places us in the sonic space of the tree. The spectral frequency of this recording also allows us to understand the tree in a new way.
What does the attack, decay, sustain, release profile of these mallet strikes tell us? Can the heartwood be read from the signal? Or does the variation simply indicate the difficulty in maintaining a consistent signal from point to point? Thirdly, the dance around the tree with the mallet serves as a diagram. Certainly much more can be mined from this first test. The next step will be to frame the tree as an articulator, listening for the sounds the tree itself produces, especially as it begins to wake from it’s winter slumber.
The One Tree Project 