“New Zealand is as close as we will get to the opportunity to study life on another planet.” Jared Diamond, 1990
Today’s excursion report features another Wellington sanctuary – this time, one dedicated to native plants. Otari-Wilton’s Bush is a 100-hectare botanic garden and reserve of native forest that was protected from the timbering and clearing for farming that were common after European colonization of New Zealand.
My biophilia – love of living things – is admittedly skewed toward the animal kingdom, but one of the ways that I have learned to pay better attention to plants is by listening for their stories. These are intricately and inextricably woven into those of humans and other animals, so whenever I introduce myself and my students to a new plant, I try to make sure it happens with ecological and cultural narratives. A story does far more than provide an ID; it is one of the best tools I can think of for understanding and remembering how a plant fits in an ecosystem.
This walk through Otari-Wilton’s Bush felt like reading a collection of gripping short stories featuring narrow escapes, daring rescues, unrequited love, murder, and generosity. I had to wear earplugs to tolerate the racket of the cicadas, but that was perhaps a good thing, as it also kept me from listening for birds. In fact, as I started down the main trail, I was startled to see a large kereru, or wood pigeon, perched calmly overhead.
The kereru turned out to figure heavily as a seed disperser in many of the stories I encountered. It was only fitting that he launched me down the trail of trees.
Beilschmiedia tawa is a large canopy tree whose wood has been heavily harvested for construction. Tawa is the Maori word for “to be purple,” which likely comes from the tree’s plum-colored fruits. Tawa evolved in association with large-beaked birds, such as the moa and kakapo. The keruru is now one of only two bird species left in New Zealand (the other is the kaka parrot) capable of ingesting and dispersing the seed of the tawa in the wild.
I rounded a corner and found Nikau palm, the only palm tree native to NZ. When the Maori first came to New Zealand, they left behind a homeland with many varieties of palms that had been used for diverse essential materials. In this new place, the Nikau palm was called into service, providing leaves for thatch, basketry and cooking purposes. Its nectar-laden flowers and berries attract numerous pollinators and birds. I could see bees flying around the berries, and of course, it makes a great runway for cicadas trying to reach high places to sound off.
The story of Pennantia baylisiana (Three Kings Kaikomako) was heart-wrenching. It is endemic to the Great Island (Manawa Tawhi), of the northern Three Kings Islands. Only one wild tree remains there, discovered in 1945 – the last survivor of goat proliferation on the island. The lone female tree was unable to produce seed, so cuttings were taken in an attempt to propagate more. This effort was successful, and the species is now being widely cultivated. Otari-Wilton’s Bush has one of the offspring. It was moving to touch the leaves of this plant that so narrowly escaped extinction.
The kauri, Agathis australis, is New Zealand’s largest and one of its most revered trees. In one Maori creation story, Ranginui, the sky father, and Papatūānuku, the earth mother, clasped each other so tightly that their children were trapped between them in darkness. Their son, Tāne Mahuta (the god of the forest), pushed his parents apart using his legs of giant kauri trees and let light and life into the world. A northern species, kauri forests were nearly decimated after European settlement, where they were the timber of choice for everything from dams to ship masts. The oldest known kauri (fittingly named Tāne Mahuta) is estimated to be between 1250-2500 years old.
Northern rata, Metrosideros robusta, begins its life as an epiphyte, a plant living on the branches or trunk of a host tree. It sends down roots that eventually surround the host tree and create a “pseudo-trunk.” When the host tree dies, the rata assumes its place as one of the canopy species. This sounds suspiciously like strangulation, but since it can take up to 1000 years for this cycle to unfold, it is an epically slow death.
Pseudopanax crassifolius, horoeka, or Fierce lancewood, is an odd-looking plant, whose unwelcoming form evolved as an effective defense against large browsing birds such as moa. Like many New Zealand trees, lancewood also has the interesting adaptation of looking like two entirely different plants between its juvenile and adult stages. When it reaches a height beyond the reach of a moa, the lancewood assumes a more benign, tree-like shape along with leaves lacking spikes.
Put a bookmark here; stories of Plants from Another Planet to be continued!