From water to sky to jeans, we are surrounded by the color blue, and artists from cave painters to Yves Klein have devised ways of concocting new shades. Before the mad scientists of the Industrial Revolution turned to synthetic derivatives for pigment, the woad plant was one of the primary sources of the color blue. Now, artists are reclaiming woad as an environmentally sustainable blue. Oakland's Hive Gallery presents works by Ellen Fader, Miriam Fagen, Elise Morris, Judi Pettite, and Jessica Serran, all of which incorporate woad in varied media. Sometimes, it's just fine to get the blues.