Warning is a form of action. Germany’s post World War II art is filled with works by politically engaged artists. Joseph Beuys is part of this movement. The work, 7,000 oaks, is a rant against German industry, as his country’s lakes and forests are being destroyed by acid rain brought about by the industrial revolution. Joseph Beuys launched this collective initiative in 1982 as part of the Documenta exhibition in Kassel, central Germany. With the help of volunteers, the artist has launched an ambitious project to plant 7,000 oak trees. In doing so, the artist seeks to right environmental wrongs and restore balance.