Aristid is a musical instrument enabling composers to write music that is not based on rigid scales. It generates playable harmonic frequencies based on growth patterns of plants – Lindenmayer Systems. In order to set up a playable scale, the user can manipulate the root frequency, the length of the tree’s branches, and the angle between these branches. The combinations of generated harmonies are not only novel, but also infinite. The 31 voices put out sine waves, as these most natural of all sounds in our world. Aristid allows for unbiased musical exploration while challenging the audience’s listening habits.