One of the world's rarest trees has been saved from extinction and returned to a Far North iwi.
The tree, Pennantia baylisiana, was found in 1945 clinging precariously to a rocky slope on Manawa Tawhi (Great Island), one of the Three Kings Islands north of Cape Reinga.
The female specimen was the only one known to exist so it had no way of reproducing.
For many years the tree, also known as kaikōmako manawa tawhi, was listed in the Guinness Book of Records as the world's rarest.
The scientist who found it, Professor Geoff Baylis, brought a cutting back to Auckland and raised it to maturity at the then Department of Scientific and Industrial Research.
After Baylis died, colleagues continued to nurture the tree until about 40 years later Dr Ross Beever - a scientist from Manaaki Whenua Landcare Research - noticed it had produced fruit on a cluster of flowers.
However, the tree withered and no viable seeds were produced until Beever applied a plant hormone to the seed head, prompting it to produce mature seeds.
Since then Manaaki Whenua has propagated hundreds of saplings of the once unique tree and, in partnership with Canterbury Museum, has donated more than 200 to Ngāti Kuri, whose rohe (tribal area) includes the Three Kings Islands.
The young trees have been planted around Waiora Marae at Ngātaki, more than 50km north of Kaitaia.
Once it becomes clear what conditions best suit the tree, the iwi hopes to replant kaikōmako on the Three Kings Islands to ensure its survival in the wild.
Ngāti Kuri executive director Sheridan Waitai said the kaikōmako's return was part of the intergenerational healing and restoration of tribal land, and likened the young trees to mokopuna (grandchildren).
''Manaaki Whenua bringing our mokos home is part of that reconciliation and forgiveness ... So with science and mātauranga Māori, with lots of aroha, we can actually bring back the life to this land the way it used to be.''
It is thought Manawa Tawhi island was once covered in kaikōmako but they were decimated by goats introduced to provide food for shipwrecked sailors.
With its large glossy leaves the tree is similar in appearance to the better-known puka, also native to the Three Kings Islands.
Manaaki Whenua senior researcher Peter Bellingham said the return of the kaikōmako was a step forward in how scientists could work with Māori to conserve unique ecosystems.
''Ngāti Kuri want to reclaim and reaffirm their role as managers of their ecosystems and bring their own knowledge to problems. This process acknowledges the long history and deep connection to natural ecosystems that Māori have. As scientists, we can bring the training and experience we have to work alongside Māori.''