Pennantia

The starting point for this plant profile relates to the location of our studio, which sits on part of the land where Oratia Native Plant Nursery was founded in the late 1970s. Over the decades that Oratia NPN operated, many significant plant species were propagated and planted on the Davidson family land – although none were as important in the context of NZ botany and horticulture as ‘Martha’.

‘Martha’ was one of 2 Pennantia baylisiana seedlings that Geoff Davidson received from plants that Ross Beever had coaxed into existence through the use of hormones. The reason for this scientific tinkering was that the population of this Manawa Tāwhi/Three Kings Islands endemic had dwindled down to one female tree in the wild, and Ross was attempting to encourage the tree to produce viable fruit within its ex situ population.

Over the coming years, ‘Martha’ continued to produce viable seed, leading to the eventual scenario of the world’s former rarest tree (a single female on isolated islands) now self-seeding around Oratia NPN’s original site – including a large tree at the rear of our house that regularly produces bunches of dark purple fruits.

Which brings me to the subject of the one rule that I am bound to adhere to as we continue to plant up our land – the total abolition of mainland kaikōmako (Pennantia corymbosa) from anywhere on our property. I accept this restriction freely, as it would be a pity to disrupt the remarkable recovery of P. baylisiana by risking hybridisation with P. corymbosa.

The difference between our 2 species of kaikomako could scarcely be more pronounced. The mainland kaikōmako (P. corymbosa) is one of our many heteroblastic tree species; starting life out as a dense column of comparatively small, brownish-grey leaves before undertaking the transition to a larger, deep green leaf when it reaches 3m (as demonstrated above left).

Pennantia baylisiana, on the other hand, bears dark green, large leaves from the outset, and typically assumes a multi-trunked growth form. These differences are attributable to the differing evolutionary pressures to which each species evolved, in addition to the obvious climatic distinction between warm offshore islands and colder environments from the mainland. Northern offshore forms of several other native trees and shrubs (including pigeonwood, hangehange and tawhirikaro) exhibit similar variation within a single species (or between closely related species), with larger foliage that is often in deeper or brighter hues.

The genus has four members across Australasia, with Pennantia cunninghamii inhabiting Australia’s eastern seaboard (from Sydney northwards into Queensland) and Pennantia endlicheri confined to Norfolk Island. The latter is superficially similar to Pennantia baylisiana, but kaikōmako manawatāwhi (P. baylisiana) has thicker foliage, in addition to other differences in both its growth form and flowering habit.

The genus was named by J. R. & G. Forster on Cook’s second voyage to Aotearoa in 1775, in honour of the Welsh naturalist, Thomas Pennant.

The story of kaikōmako’s chief significance within Te Ao Māori starts with the tinihanga (deceit) of Māui. Although there are variations on how the goddess Mahuika came to transfer the seeds of fire into certain trees (either intentionally or inadvertently), kaikōmako is universally considered to be the tree to have received more of the goddess’ fire than all others – following Māui’s trickery in convincing Mahuika to gradually part with the fires that burned from the ends of her fingers and toes.

This legend acted as a practical repository of the knowledge that kaikōmako is the best wood for the hika – the harder timber that is runs through a groove in a piece of softer timber (normally mahoe) known as the kauahi. This method of starting fire (known as hika-ahi or fire plough) is vividly described in James Cowan’s account from Volume One of ‘Legends of the Māori”² :

“One of my earliest recollections is that of the hika-ahi act, the kindling of fire by wood friction, demonstrated at our old home at Orakau, Waikato. Māori were frequent visitors, and Māori labour was employed at times on the farm, and one day two men, at my father’s request, showed how fire was produced without pākehā matches or flint and steel.

By the stockyard fence, one toiled away rubbing a stick on a block of wood which the other held steady while a shallow groove was worked in it. I looked on, a small boy, intensely interested in the strange sight of old Ngata, of Ngati Raukawa, on his knees rubbing away furiously to raise the seeds of fire. I remember vividly enough the sight, but it took a long time to produce a spark; perhaps it was not kaikōmako wood, for that is the chief timber in which Mahuika’s magic flame is preserved for the use of mankind.”