Berberidaceae: Barberry Family
The Barberry family includes the eponymous barberries (closely related to the cultivated Mahonias). It also includes the completely different Inside-out Flower or Redwood Ivy, for reasons that would be clear only to professional botanists. Barberries can be tricky to identify with certainty. Jepson’s Barberry appears to be confined to the southeastern part of the county, whereas the California Barberry is more common on the Peninsula. But there are plants found on the Peninsula that in seem to share features of both, so one needs to be cautious about one’s identification.