Chinese-born artist O Zhang traveled across the United States, photographing thousands of blank and neglected billboards, a trek that echoes Dorothea Lange’s own documentary expedition during the Great Depression. Zhang has taken an object that has long been a canvas—with pop art icons such as Andy Warhol designing billboards for the Sunset Strip—and made it the subject instead. In capturing the formal elegance of the bare billboard, Zhang has, in some sense, flipped the script. It’s not the printed images and text on them that matter, but the structures themselves. Read more about her work and about billboards as an American cultural signifer in my essay for The Margins, a magazine of the Asian American Writers Workshop.