Porcelain berry
Mom and I had never heard of the Elisabeth Gamble House (and garden) just up the road from her place before my online search for "gardens Santa Clara County". I was in the mood for a visit to a garden.
A large gazebo in the garden had several climbing plants. I had never seen this plant before and was delighted by its many-colored berries. I thought out loud with Mom nearby, "I wonder if this might not be such a good plant to have, dropping berries, perhaps reseeding all over the place..." An online search since our visit reveals that this is one of those plants that many states wish they could get rid of because it takes over.