New Zealand.

What unknown affinity

Lies between mountain and sea

In country crumpled like an unmade bed

Whose crumbs may be nuggets as big as your head

And it’s all snow-sheeted, storm-cloud fed?

Far behind is the blue Pacific,

And the Tasman somewhere ahead.”

The Search by Dennis Glover (9 December 1912 – 9 August 1980)

New Zealand lies in the collision zone between the Indo-Australian and Pacific tectonic plates, and more than 15,000 earthquakes a year take place although few are strong enough to be felt. A major exception was the Kaikoura earthquake of November 2016 which buckled the east coast of the South Island and moved the north-eastern tip of the island closer to the North by over two meters (6.5 feet). It was the most complex earthquake ever studied, ripping through 25 fault lines and changing the way fault ruptures are now measured. It also scared the shit out of a lot of people, including this writer who was present at the time.

 As pleasantly benign as New Zealand appears, with its English-style gardens, safely grazing sheep, and rivers of Sauvignon Blanc, it is a violent country, heaving and swaying, rising and falling through geological time. Those of us who don’t know, and that is most, may think of plate tectonics as a series of dinner plates rubbing up against each other rather politely until something breaks. But the plates are broken crockery hurled by violent forces as if in some argumentative Thanksgiving dinner, while all the time the dinner table itself bubbles with volcanic eruptions.

And what we humans feel is just the surface. Underneath the underneath, it is a different story. New Zealand as we think we know it keeps bouncing above and below the water line like a rubber duck in a child’s bathtub. What we see today is just a remnant of a continent formed about 83 million years – the continent of Zealandia. Now we know that New Zealand, Stewart Island, New Caledonia, the Chatham Islands, and other small islands are the tops of a submerged continent 1,900,000 square miles (4,920,000 square kilometers) in size.

75 per cent of New Zealand is mountainous or hilly, Aoraki / Mount Cook is the highest at 12,218 feet (3,724 meters). The Taupo volcano is in the center of the North Island and 26,500 years ago, it produced the world’s largest known eruption of the past 70,000 years. The fjord-like coastline is 9,300 miles (15,000 kilometers) long. About 15 per cent of the land is covered in plants, and 80 per cent of the plants are endemic to the country. It is this high rate of endemism plus its geographical isolation that makes New Zealand one of the most interesting countries on earth. Looking to New Zealand’s iconic plants, we can see why. Agathis, Pseudopanax, Cyathea, Dicksonia,Rhopalostylis, Metrosideros, Leptospermum, Nothofagus, and Podocarpus, give us clues to why New Zealand is so special.

In the Kaipoua Forest in the northwest of New Zealand’s North Island stands the Lord of the Forest, Tāne Mahuta (Agathis australis). It is estimated to be 2,500 years old and is 168 feet (51.2 meters) high. The genus Agathis belongs to Auracariaceae family, a family of tall coniferous trees, all but for a few south-east Asian species, growing in the southern hemisphere.

Agathis asutralis

The Lord of the Forest is not the tallest but with a girth of 45 feet (13.77 meters), it is the largest in New Zealand. To stand beside it is to experience something that can only be called awesome, in the proper sense of the word. To stand in awe of something so powerful, set apart from human time and human life, is a great and sacred gift.

In the Māori creation story, Tāne Mahuta created the earth by lying between Ranginui, the sky father and Papatūanuku, the earth mother. All forest creatures are Tāne Mahuta’s children. There are many children in the Waipoua forest. The forest shelters what remains of the endangered North Island kokako, sometimes called the blue-wattled crow; the brown kiwi, kukupa/kereru the New Zealand wood pigeon, and the very rare kākāpō, a ground-dwelling parrot.

The kauri is a successful species due, in part, to its ability to poison the ground around it. The leaf litter surrounding the trees is acidic, preventing other species of plants from thriving. That’s not to say that a Kauri forest isn’t abundant, away from the very base of the tree, is a rich and diverse flora.

In the forest grows dense stands of kauri grass (Astelia trinervia) growing to a height of 8 feet (2.5 meters) with a width of 6 feet (2 meters), and often seen with kiokio, crown fern (Blechnum discolor) a shuttle-cock shaped bright green fern. Ferns are abundant, Blechnum fraseri can develop slender trunks up to 3 feet (1 meter) high, while the shiny fronds of kidney fern – kopakopa (Hymenophyllum nephropyllum) reach to 4 inches (10 centimeters) tall. Mairehau (Leionema nudum) is a shrub with scented leaves and white flowers and grows up to   13 feet (4 meters).Hangehange (Geniostema ligustrifolium), looking a little like privet, has greenish-white scented flowers and was used by the Māori to flavor meat.

Hymenophyllum nephropyllum
Blechnum fraseri

Seen too, is the toothed lancewood, horoeka (Pseudopanax ferox), a sculptural small tree with juvenile downward growing fiercely toothed leaves, this and Pseudopanax crassifolius are grown by gardeners, a habit that endangers Pseudopanax in the wild.

Pseudopanax

Scattered throughout the forest and growing prominently around the edges are the tree ferns. To say that they are iconic is literal truth, the silver fern – ponga (Cyathea dealbata), is the symbol of New Zealand and is seen on the uniform of New Zealand’s rugby team, the All Blacks. Cyathea dealbata is a slow-growing tree fern with distinctive silvery undersides to the fronds. Mamaku, the black tree fern (Cyathea medullaris) is the most common of New Zealand tree ferns, it is also the tallest growing to a height of 65 feet (20 meters) and is identified by its black trunk and hexagonal bases of the frond stems. Wheki (Dicksonia squarrosa) tends to grow in colonies and grows to 26 feet (8 meters tall). Close to the Kauri forest, all three species can be seen growing with extravagance alongside riverbanks with another iconic New Zealand plant, nikau (Rhopalostylis sapida), the only palm native to New Zealand.

Cyathea dealbata
Cyathea medullaris
Rhopalostylis sapida

Along the coast grows the New Zealand Christmas Tree, (Metrosideros excelsa), pōhutukawa, the most colorful of trees in the islands, with bright crimson flowers in late December on a multi-trunk, spreading tree. An 800-year-old tree holds a special place in Māori mythology. The spirits of the dead descend the tree into the underworld (Rēinga) to begin the journey to the homeland of Hawaiki.  It is a widely cultivated tree but is under threat in the wild from possum (Trichosurus vulpecula), and stock browsing. Fortunately, Project Crimson, – a nonprofit organization set up to protect pohutukawa forest, has been very effective.

Metrosideros excelsa

Mānuka honey may well be the most sublime tasting honey in the world. Mānuka is the Māori name for ,a fast-growing evergreen shrub or small tree with oval pointed leaves, and white or pink red-centered flowers throughout the year. It and its cultivars are widely grown in gardens and it is widespread in New Zealand although the recent arrival of myrtle rust, a fungal disease, may become a serious problem. The honey, from bees feeding on Leptospermum, is very sweet and rich and is claimed to have antibacterial and immune boosting properties. These are claims that should be taken with a spoonful of honey.

Leptospermum scoparium

The Kauri forests are a rich and profoundly important flora, once covering almost 3 million acres (1.2 million hectares) before the first people arrived 1,000 years ago. The first European to sight the islands was the Dutchman, Abel Tasman. Captain James Cook  made landfall in 1769. European settlers followed and the Kauri forests were harvested for the timber and gum. Clearing for farmland and timber increased up to the mid-20th century. Today, the remnant population of mature kauri covers just 18,420 acres (7,455 hectares) and is susceptible to damage from possum and from Kauri dieback, a serious soil-borne fungal disease.

There is, for once, cause for optimism, conservation efforts appear to be succeeding and abandoned farms with regenerating secondary forest and scrubland contain an estimated 148,000 acres (60,000 hectares) of kauri and its associated flora and fauna. Well-managed timber operations are also contributing to the regeneration. Private organizations; the Waipoua Forest Trust (a joint partnership between the Forest Restoration Trust and Te Roroa, the Māori guardians of Waipoua), Kauri 2000, and the Puketi Forest Trust are working with the Department of Conservation establishing thousands of kauri seedlings on suitable sites.

There are two other key genera of trees in New Zealand. Both have significant flora associated with them and both connect to species elsewhere on the planet. The Southern Beeches, Nothofagus, consist of 37 species of deciduous and evergreen trees only found in Australia, Chile, Argentina, Papua New Guinea, Indonesia, New Zealand and New Caledonia. New Guinea has the most species, fourteen, while New Zealand has four with one additional variety; Nothofagus menziesii: silver beech, Nothofagus fusca: red beech, Nothofagus truncata: hard beech, Nothofagus solandri var. solandri: black beech, and Nothofagus solandri var. cliffortioides: mountain beech.

Nothofagus sp.
Nothofagus fusca

There’s an old bushman saying about southern beeches, ‘You’ve got three types of beeches – red, brown and black. The bark of the red is silver, and the wood of the red is pink when its green. The brown quite often has black bark, but the green timber is red. Sometimes the bark of the black is white, but the timber is yellow and sometimes brown when it’s green.’ Now that’s cleared up, taxonomists add to the confusion with virulent (if taxonomists can be said to become virulent) argument as to whether the New Zealand beeches are Nothofagus, Fucospora or Lophozonia. The argument is best left to science. In the meantime, Nothofagus will have to do.

Nelson Lakes National Park is situated in the north of the South Island. It is about 2 hours drive from the city of Blenheim and protects 252,000 acres (102,000 hectares) of the northernmost range of the Southern Alps. It was formed during the last Ice Age by glaciation and by the mountain up-thrust along the Alpine Fault. Now the valleys are forested with red and silver beeches in the lower elevations and the mountain beech at higher altitudes. Once threatened by over-harvesting, the pressure on New Zealand’s Nothofagus has now eased, thanks, in part, to national parks such as Nelson Lakes. The changing climate in New Zealand may have an as yet unknown effect but drier conditions are not in the trees’ favor.

Nothofagus fusca, tawhai raunui, the red beech, is the most commonly seen growing along the shores of Lakes Rotoiti and Rotoroa. It is an evergreen tree reaching a height of 114 feet (35 meters) tall. The leaves are characteristically double-toothed. The foliage of young trees has a reddish tinge while mature trees have bright green leaves. It is a dominant species, creating large forests, often colonizing exposed areas. In some areas red beech and silver beech, Tāwhai (Nothofagus menziesii), grow together although silver beech reaches into higher altitudes.

The New Zealand podocarps consist of eight genera with native species, Podocarpus, Dacrydium, Prumnopitys, Dacrycarpus, Halocarpus, Lepidothamnus and Manoao. Of the eight, Podocarpus is the most significant and in that genus, tōtara, Podocarpus totara var. totara is the most widespread. Tōtara is a slow growing evergreen reaching a height of 80 feet (25 meters). Pouakani, the world’s biggest tōtara, is 1,800 years old, and is 140 feet (42.7 meters) high and 41 feet (12 meters) in girth.

Podocarpus totara

Tōtara is almost indistinguishable from Podocarpus nubigenus, a species native to the Valdivian temperate rain forest of Chile, and therein lies the story and raging debate of Gondwana flora and plant colonization.

Where did the plants now growing on Zealandia come from? For some, the answer may be blowing in the wind, that is long-distance dispersal. And that means they blew in or came across the sea from somewhere else. For others, they were there when the super-continent, Gondwana, broke apart to form the continents as we know them resulting in differentiation of the original group into new varieties or species. That is vicariance. The Nothofagus in Chile are different species than the Nothofagus in New Zealand, for example.

Much has been published and will continue to be written about the origin of plants in Zealandia and this ever-unfolding story is why New Zealand is one  of the most interesting countries on earth.

Nelson Lakes

Author: urbanehorticulture

A native of England a U.S. citizen for the past 30 years, I have worked in the garden world as a director and designer for over 35 years. I am best-known for my groundbreaking designs at Chanticleer, an estate and “pleasure garden” in Wayne, PA, where I worked for 20 years. Career Highlights I started my gardening life at the Royal Botanical Gardens, Kew, England, where I was trained as a gardener. I worked in three other gardens in the UK, notably Portmeirion in Wales, Bateman’s in Sussex, and Cliveden in Buckinghamshire. At Bateman’s, I was responsible for the restoration of the 17th-century garden. I came to the U.S. in 1981 and was director and chief designer of Chanticleer in Pennsylvania for the next 20 years. I transformed a moribund private estate into one of America’s most exuberant, romantic and flamboyant gardens. Its glorious 47 acres have been celebrated by gardeners and horticulturists from around the world and, based on my designs, it continues to draw international visitors every season. After twenty years creating Chanticleer, I became vice president for horticulture for the Santa Barbara Botanical Garden and, in 2006, was appointed director of the VanDusen Botanical Garden in Vancouver, Canada. While pleased to be in Canada, my heart yearned for California and in 2008 he was appointed executive director of the Mendocino Coast Botanical Garden. After a successful period in northern California, he returned to his home near Santa Barbara, CA where I operated my own design-consulting business. In 2012, I was lured back east by The Pennsylvania Horticultural Society (founded in 1827) and appointed director of its private estate and garden, Meadowbrook Farm. I was commissioned by PHS to design the central feature for the 2013 Philadelphia Flower Show, the third major exhibit I have designed for PHS over the years. Among numerous other responsibilities, I have been a member of the board of the Fairmount Park Conservancy in Philadelphia and a founding member of the business advisory board for the Flora of North America Project. I have designed gardens in Chicago, northern and southern California, and throughout the Northeastern United States. I have also been a consultant to the Garden Conservancy and to Botanic Gardens Conservation International, as well as serving on the horticulture advisory committee of Lotusland in Santa Barbara, California. I have been the Advancement Advisor for the Flora of North America Association and am now traveling the world researching, interviewing, and photographing for a book on gardens around the world. Books & Awards My n first book, The Encyclopedia of Perennials, was published in 1992 by Facts on File. I also contributed to 1001 Gardens to See Before You Die (Barron's Educational Series, 2012) and The Gardener’s Garden (Phaidon Press, 2014). In 2003, I was awarded the Professional Citation for significant achievements in public horticulture by the American Public Garden Association. In 2007, The Pennsylvania Horticultural Society awarded me its prestigious medal for Distinguished Achievement. I currently live in the Bay Area, California.

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