Thallus is musical scores, made from lichen.

It provides a means to ‘perform’ the many diverse communities of lichen found underfoot in the environment of Kilpisjärvi in Northern Lapland, Finland. Scores are generated on a per-performer basis, and are based on the synthesis of traditional notation with lichen samples from the environment.

Thallus was performed at the Fourth International Conference on Technologies for Music Notation and Representation (TENOR 2018), by Ensemble Supermusique, using Decibel Score Player.