Karaka

Corynocarpus laevigatus

endemic to New Zealand and the Kermadec and Chatham Islands

The Karaka trees of the Tangihua bush are found

Karaka tends to be found on the easier country. Around the lodge it can be seen on the nature trail

Description of The Karaka

Karaka is a leafy canopy tree with erect or spreading branches growing up to 15m with a stout trunk up to 1m in diameter. The thick, leathery leaves are glossy, dark green above and paler beneath, 50–200 mm long, and 30–70 mm wide with petioles 10–15 mm long.

Karaka produces stout, erect panicles of tiny flowers. Individual flowers are 4–5 mm in diameter and greenish-cream to off-white or pale yellow In winter and spring

The fruit is an ellipsoid to ovoid drupe 25–46 mm long, with pale yellow to orange flesh, containing a single seed.  The fruit ripens in summer and autumn  and the seeds are mostly dispersed by birds.

Karaka is thought to native only to the northern half of the North Island but was transplanted to other areas by Maori

(note by editor) Kayaking we found a small grove of Karaka in Pelorus sound which is considered well south of its natural spread. it may well have been planted by Maori

Karaka trees are an important source of food and habitat

It is of great value to birds and other fauna, including invertebrates that feed on their fruits and disperse their seeds. The ability to bear fruit in winter makes this tree an important food source for many species at a time when resources are scarce.

Kereru swallow  the fruits whole, they then disperse the seed

Karaka berries are very poisonous

Under the orange skin of the fruit is an edible pulp. The kernels of the berries contain the neurotoxin and the powerful alkaloid poison karakin. Karakin is toxic to birds, bees and mammals, but is destroyed when heated for an hour at 100°C.

Initial signs of karaka berry poisoning are nausea, diarrhoea and restlessness. These quickly progress to more severe gastrointestinal and neurological issues, including pacing, limb rigidity, crying, seizures and then unconsciousness.

The kernels are highly toxic to dogs who often like the flesh of the fruit but digest the kernels as well.

Significance to Maori

Karaka is the word for the colour orange in Maori which is the same colour as the berries when ripe.

They were an important source of food for Maori but had to be carefully prepared to avoid poisoning. Karaka was one of the very few native trees planted by the Maori. Groves of karaka trees were planted near the bays and harbours they seasonally visited.

Māori discovered how to make karaka berries safe for eating. Once the ripe berries had fallen from the tree they were ware gathered and then trampled with the bare feet in water to remove the outer fleshy part. The kernal was then baked in a hangi for 24 hrs and then immersed in running stream water for one or two weeks. The kernels could then be stored for several months. Re-cooking softened them for eating.

The raw flesh of the bright orange fruit is edible, with a strong apricot flavour.

References

• The meaning of trees