Aristolocaceae, Aristolochia california, California Pipe Vine
Previously I had only encountered Aristolochia vines in the tropics where some species have massive flowers. Here is a link to some previous post on some of the tropical species. Aristolochia californica, depicted below, is native to moist woodlands and riparian zones throughout North and Central California. Some of the tropical species have medicinal properties, I’m not sure about this one.