Kim Knight meets the man who his way around New Zealand's forests.
The New Zealand bush is an acquired taste. Bitter, sweet, nutty - and turpentine.
"Very turpentine," says Robert Vennell, the softly spoken boy scout of a man who can make coffee from karamū and personally vouches for the diarrhoea-busting power of koromiko.
"Nothing tastes great, if I'm going to be totally honest ... but you can sort of acquire the taste if you persevere. I try to remind myself that a lot of plants are not necessarily nice if you just grab a handful and munch on them. You've got to find a way to unlock their potential."
Chicken marinated in miro berries. Horopito-spiked hot chocolate. Salad from the new shoots of a supplejack - but not the tutu, as one would-be forager recently found out.
"He took the shoot home and boiled it with carrots and broccoli for dinner but found it tasted revolting and quickly spat it out. Later that night, he turned blue, began foaming at the mouth and was racked by seizures so severe they threw his arm out of its socket."
Incredibly, reports Vennell, two circus elephants, in two separate incidents, have been killed grazing on the highly toxic tutu.
Vennell has a masters in conservation and biosecurity (thesis topic: a damage function for wild pig rooting in temperate rainforest) and a day job that involves collecting and preparing specimens for the natural science galleries at Auckland Museum. Six years ago, he set himself the task of eating every edible plant in the New Zealand bush.
The result was a blog that has grown into a just released book, The Meaning of Trees (HarperCollins New Zealand, $55). It tells scientific, historic and cultural stories of New Zealand bush; what our plants taste like, what they have been used for and why trees matter.
"Plants have a tendency to blend into the background and we don't really appreciate all the ways in which they influence our lives," says Vennell.
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Humans, for example, literally floated to Aotearoa on plants. When they got here, it was plants that provided clothes, shelter, food - and even defence.
Consider the mangemange. "At first glance, the thin, wiry stems look easy to break," writes Vennell. "But they are much stronger than they appear. Māori often used a single narrow stem of mangemange to saw pounamu in half, grinding down bare rock with water and sand. Mere humans stand no chance and trampers often find themselves strung up by the plant, snagged around the body, arms and ankles struggling to break free. British soldiers roaming in the bush would frequently catch their bayonets on the vines, leading many to adopt knives and revolvers instead ... "
Mangemange was used for eel traps and whitebait nets - and mattresses. The plant is so springy, Pākehā settlers called it the "bushman's bunk", stuffing coiled vines into sacks to keep sleepers off the hard ground.
"It's a cool plant," says Vennell. "And when you look at it, you're surprised to learn it's a fern as well."
He's perched on a stool in a staff-only corridor at Auckland Museum. It's lined with tall cupboards. "Albatross skins" reads the label on one door and, inside, enormous, pillowy birds are stacked like a demented fairground prize wall. Another door reveals snakes en masse. Vipers and pit vipers and, on the bottom shelf, a taxidermied tuatara.
"Amazing, eh?" grins Vennell.
But it's easy to be enraptured by reptiles, birds and animals. Plants, says Vennell, are harder to love.
"They're not cute and fluffy, they don't have big eyes and feathers, so they're starting on the back foot."
He can't pick a favourite but says, "One that I had to include in the book, even though it was pushing it a bit and it's not really a plant, was bull kelp."
An "otherworldly creature", writes Vennell. "With its long tentacle-like blades stretching up to 10m, swirling back and forth in mesmerising patterns in the surf."
Slit open a strand of kelp and observe its honeycombed air pockets that can be inflated and used as a pōhā or container for carrying water and food (and preserving tītī, the muttonbird that breeds on islands in the deep south). Kelp was used for makeshift wetsuits and footwear for gathering kaimoana but (and this is what really appeals to Vennell) its bulbous stalk was also carved into bouncy balls.
"It's got this compound that helps with that springiness ... that blew me away."
Yes, he did try this at home.
"It hasn't kept that well ... "
The quirky sits alongside the poetic. Pīngao is an amber gold coastal sedge. Once widespread and highly sought after by weavers, it has experienced massive decline.
"All of the most prestigious plants had legendary origins," writes Vennell.
One story says pīngao began life as a seaweed who fell in love with the handsome, blond-locked kākaho- the flower stalks of the toetoe. Crazy in love, she crawled across the sand to meet the tall stranger. Stranded in the dunes, she called out to her father, Tangaroa but all he could do to help was shower her with sea spray every incoming tide.
"However," notes Venell, "The lovers do occasionally meet, as pīngao is often woven together with the kākaho to form tukutuku panels on the marae."
His criteria for inclusion in the book: "Is it cool? Is it interesting? Is it going to make people fall in love with these plants?" It is, perhaps, the first time a single book has captured so many aspects of the New Zealand bush - from traditional uses and origin stories, to etymology to contemporary medicinal and scientific applications.
Tōtara, for example, contains a chemical compound, dubbed totarol. Subsequently discovered in other podocarp and cypress families, totarol is now used in anti-ageing creams and in the treatment of acne and dental plaque. Poroporu contains a steroid precursor, solasodine - plant extracts are used in anti-inflammatory skin creams - and Vennell reports that scientists from the former USSR took the plant to the Soviet Union to study its potential in the creation of steroid drugs.
Vennell says New Zealanders are often told there is nothing edible in their native bush. He cautions some plants can make people very sick - kōwhai, for example, is poisonous. And bracken, which was once widely consumed, is now a known carcinogen. He says he never got sick in his quest.
"I had a rule that before I put it in my mouth, I had to know what it was and what it had been used for ... and there is an extra motivation, when you know it could have been really poisonous."
He thinks his interest in trees goes back to his childhood fascination with survival stories.
"I'd always get piles and piles of books about people lost in the wilderness and anything about people forced to battle the elements and things like that."
Single most useful plant if you had to make a life in the New Zealand bush?
"Harakeke," says Vennell, with no hesitation.
"You can do just about anything with it. You can make rope and clothing. You can eat it - there's a gum at the base of the leaves and you can drink the nectar from the flowers and you can eat the seeds. People have made a kind of coffee out of them."
We've left the museum now, and crossed the domain to the start of a bush track. You can hear trains and cars and sirens - but also fantails and the swoosh of a kererū. Many of New Zealand's native berries have finished flowering, but you can chew kawakawa year-round. The heart-shaped leaf with the hungry caterpillar holes is a relative of kava - it lacks its relaxing properties but it will make your mouth numb and, says Vennell, is delicious brewed as a tea.
Next stop: Ponga. "I suppose having a fern as part of a country's national identity is less common - most things like that are a a flower. It makes sense in a way, because we do have a really high diversity of ferns and it's a really obvious, visual thing, when you walk into a forest. All those big tree ferns."
Fun silver fern fact: Their pale undersides gleam in the moonlight and Māori would lay them on the ground as night-time route markers.
Vennell says sometimes he tries to imagine what it was like for the first arrivals to Aotearoa.
"It would have just been like nothing they were used to. It would have been amazing. Mountains, glaciers and just forests everywhere. New Zealand would have been just about entirely covered in forest at that point, and the land mass itself would have been larger than all of the islands in Polynesia put together.
"We're used to thinking of New Zealand as a very little country at the bottom of the world. But for those explorers, it would have been absolutely immense ... finding an entirely new land that no humans had ever seen, that had evolved in isolation for millions of years and gone down a different trajectory from everywhere else. Getting to see all of those things for the first time would have been pretty crazy."
The biggest trees in this little patch of Auckland Domain bush are imports. The canopy is all giant oaks, but Vennell points out pōhutukawa, cabbage trees and a kahikatea. At ground level, we can see rewarewa (a favourite among landscape gardeners) and a young nīkau - known by foragers as "millionaire's lettuce" because while the heart of the palm is tasty, its removal spells the tree's demise.
"You can also eat the green, unripe berries," says Vennell. "Once they ripen up, they're too hard. Super-dense. They were used as spare shot for ammunition."
There's māhoe , the fire tree. Mānuka, the so-called "tea tree" that also occasionally secretes a gum that was used as a moisturiser for burns. Tarata, or lemonwood, because when it is crushed, it releases a lemony scent.
"When you look around at plants today, 95 per cent are flowering. They're kind of like the young upstarts that have taken over the show. The kauri and the podocarps are the old, slow-growing things. They were in charge back in the day, but now they just sort of hang on in these hard-to-grow places."
Did you know that the biggest fuschia in the world lives in New Zealand? That, up north, there is a tree called Bartlett's rātā and its flowers are white, not red, and there are only 30 of them left in the whole world? That there is a theory that says this country has so many plants with divaricating leaves because they evolved in that messy, tangled manner to protect themselves from browsing moa?
"When I started out," says Vennell, "It was just one green plant and another green plant and how do you tell the difference? But in doing this, it just kind of clicked. They're all so different to me now."
Earlier this year, a Danish study found that children who grow up in green spaces are 55 per cent less likely to develop anxiety and depression later in life. A New Zealand study has determined people who live close to parks are less likely to be overweight or obese.
"To be honest," says Vennell, "When I am in the bush, I just feel like I'm back in my element. I always feel uplifted and excited. There's always something cool to find, something new that you haven't seen before."
The Meaning of Trees by Robert Vennell, HarperCollins, $55.