The Columbia Tree in Columban, America, Bitter Oranges 

Adolf Wölfli made 'The Columbia Tree in Columban, America, Bitter Oranges' using coloured pencils and graphite on paper. The piece is incredibly dense, with layers of meticulously rendered forms. Look at the time that it must have taken to create all those fine pencil lines, building up the image, and layering colours and forms. Wölfli was a patient at the Waldau mental asylum near Bern when he made this drawing. His whole approach to artmaking was about compulsive labour, filling every available space with image and text. He was committed to it, day in and day out. 'Outsider Art', as it came to be known, is a fascinating category, partly because it brings up these questions of making and production so forcefully. It prompts the question: what does it mean to make something outside the normal channels of artistic exchange and economy? What kind of freedom does that offer? It certainly sets Wölfli’s images apart from the ordinary art world, with its usual concerns about markets and career trajectories. It is in works like this that we can really understand the importance of materials, making, and context in understanding the full meaning of an artwork, and challenge traditional distinctions between fine art and craft.