The University's surprising biodiversity

In 1945, on one of the Three Kings Islands, north of Cape Reinga, Professor Geoff Baylis found the world’s loneliest tree.

The island’s vegetation had been ravaged by goats, but on an inaccessible slope, the botanist discovered the very last Pennantia baylisiana.

Today that tree, also known as the Three Kings kaikōmako and for many years as the world’s rarest tree, thrives in a small garden on the City Campus alongside other plants endemic to New Zealand’s northern offshore islands.
Plant ecologist Bruce Burns, an associate professor in the School of Biological Sciences, explains that although cuttings were successfully grown from that sole female Pennantia baylisiana in the 1950s, it was not until 1985 that a specimen was induced to self-pollinate and produce seeds – ultimately bringing the species back from the brink of extinction.

The tree is one of many rare, historic or otherwise interesting plants on the City Campus, which is home to a remarkable collection of biodiversity.

In 2018, Bruce kicked off a citizen science initiative that allows anyone to upload their observations of different species on campus to a website, to document the area’s biodiversity.

At the time of writing, 3,794 observations had been made by 392 observers identifying 1,321 different species – from plants and insects to fungi and birds.
“It really is a green oasis in the middle of the city, so we should be looking after it,” says Bruce.

“That means the University needs to think about how it’s approaching its responsibilities to biodiversity maintenance and how we protect and enhance the amazing collection of species we already have here.”

As part of its biodiversity efforts, the University is a member of the Nature Positive Universities network, which aims to harness the power and influence of universities to lead biodiversity-promoting work in their communities.

Bruce regularly uses the grounds around Old Government House for teaching and research, and he has a mine of fascinating stories to go along with the variety of specimens that grow there.

Another extremely rare tree, growing alongside the Biology building, is a Metrosideros bartlettii (rātā moehau) – a species endemic to the Far North that has been ravaged by possums to the point of just 14 examples surviving in the wild. Related to the pōhutukawa, it’s also rare among its red-flowering relatives for having white flowers, says Bruce.

Plants on the City Campus grounds also tell the story of the area’s history. Pre-1840, the area in front of where Old Government House now stands was a potato field. It was bordered on the north by a flax colony in an area where the flax still grows today.

A huge Erythrina afra (coast coral tree) in front of Old Government House has stood sentinel since it was planted there by Governor George Grey in the early 1860s – a specimen he brought to New Zealand from his travels in Africa. While it has recently undergone some ‘surgery’ by arborists to improve its overall health, Bruce notes it will grow back and, hopefully, be a feature of the grounds for many more years.

All the area’s trees, however, are dwarfed by a 50-metre Norfolk pine, which was planted in 1869 by Queen Victoria’s second son, Prince Alfred, alongside a giant sequoia. Dignitaries ranging from Queen Elizabeth II to Sir Edmund Hillary, and successive vice-chancellors are among other notable figures who have planted trees on the grounds.

Then there are those trees that are just plain interesting.

There’s the candle nut tree, whose nuts, as the name suggests, can be cracked open and used as a candle by lighting its oil. Or the Ficus religiosa, or sacred fig – the species under which Buddha is said to have received enlightenment, and is considered sacred in three further religions. Or the Camptotheca acuminata, known as the happy tree, whose bark is the source of a compound used in many anticancer drugs.

There’s also the Turkish pine that grows next to Maclaurin Chapel, which descends from the sole pine that once grew on the site of the Battle of Lone Pine in Gallipoli. Its position is particularly poignant, says Bruce, given the chapel was built in memory of pilot Lt Richard Maclaurin Goodfellow, who was killed in World War II.

But Bruce’s favourite among all the weird and wonderful plants on the City Campus remains the Pennantia baylisiana.

Bruce met Geoff Baylis, but also knew Ross Beever, the scientist who obtained viable seed from the plant in 1985 helping ensure the survival of the species.

It’s a reminder, he says, of the interdependence of plants and people.

“The big picture is that the biodiversity of species in an ecosystem strongly links to the health of that ecosystem and, given our lives depend on our ecosystems – for food, medicines, clean water and soil and so on – biodiversity is something that deserves our attention.”

– Caitlin Sykes