Yes, I noticed the state of the hills between Kairakau and Waimarama. Mohi Bush was the other reserve. It sounds like you'll be back at Elsthorpe, if so and you still want to pin it down, it should be easy enough to work out what the vine is from fallen leaves as Mike suggests. M. colensoi and M. perforata are very distinct and the photos on NZPCN are quite clear.