Lichen is an ongoing research into the relationship between various lichen and butterflies that use them as host plants. The images originates from a photo taken on the old roman walls in the city of Maastricht. In the Charles Nypels Lab at the Van Eyck Academy in Maastricht this photo is printed as a riso-print in different color layers. Filtering the layers of color creates an insight into which types of lichens can be seen on the image and their growth forms. The types of lichens are often unrecognizable in their natural habitat where they often fuse together as if it were one large lichen.