In the fall, a group encased trees throughout the Ped Mall with sleeves of yarn, like this. Think of wrapping the quilt you have in your basement around a tree and letting it shrink to size as it wets and dries. This is not unique to Iowa City; in fact, "yarn bombing," as it is called, is growing to be a widespread feminist form of graffiti art: http://www.nytimes.com/2011/05/19/fashion/creating-graffiti-with-yarn.html
Banksy's Graffiti, Animated
Fotos de los mejores grafitis realistas
Fotos de los mejores grafitis realistas - Taringa!