Check that page, it's one of the best interpretations of California's odd and often vague knife laws. Basically, open carry of any blade is fine. You could carry a 5-foot Scottish claymore if you choose. But you can't conceal any fixed blade knife, or anything that could be readily used as a stabbing weapon. That could be anything from a bowie knife to an ice pick, or even a knitting needle or ballpoint pen. Did I mention the law was vague? But I seriously doubt that anyone could argue that an axe or hatchet is a stabbing weapon. It's far more cutty than stabby. And axes are not mentioned anywhere by name so you should be good to go.