It looks like Araujia sericifera, cruel vine, moth plant, bladderpod, an escaped ornamental that has become an invasive weed in California.

Here is a link that might be useful: Araujia sericifera, cruel vine, moth plant, bladderpod

Very good, thanks! I wouldn't have thought to look for native New Zealand plants when trying to identify a wild vine in California. Yes, that definitely looks like the same plant.

Here is a link that might be useful: Weeds of New Zealand

Hi Simnia,

My pleasure to help. This plant is not native to New Zealand, but instead to South America. It is among a large number of plants that have become invasive troublemakers in California, Australia and New Zealand. -All three areas have similar climates and so provide hospitable environments to some of the same alien plants. In California, Araujia sericefea is a pest in citrus orchards and so causes some economic damage to our state.