Rugged on Rēkohu
Botanic field trip 2024
When Botanic was founded in 2022 we decided that each year we should undertake a ‘field trip’ to a natural landscape or area of botanical interest. Going together with family would help to recharge our batteries and also help us continue to learn about different plants and botanical communities. The trips are also a chance to tick off a few business related tasks that need doing. In 2023 for our field trip we took the TranzAlpine train up to Arthur’s Pass and had a poke around the Beech forests and subalpine areas there. This year we decided to go further afield and explore the Chatham Islands - somewhere none of us had been before.
Beautiful landscape… beautiful people
The islands were named Rēkohu by Moriori and Wharekauri by Māori. There is a complex and sad history of conflict and exploitation on the islands but also an inspirational kaupapa of peace. The islands are now home to around 800 locals, and as visitors we felt the warmth of their hospitality, meeting many friendly folk who were happy to yarn and share stories. We stayed at Owenga on the east coast of Rēkohu which is a hub for the island fisheries.
A trip highlight was the local kai moana - with koura / crayfish, blue cod and paua featuring on our dinner plates during the week. Our visit coincided with the annual pig hunting competition and community festival. Feeling the need to represent, the Botanic team joined in on the tug-of-war, gumboot throwing and (pig carrying) obstacle course… but placed well behind the impressive local talent!
Botanical investigations
Pastoral farming forms a large part of the Rēkohu landscape, but dotted around are several remaining natural landscape gems providing a refuge for native flora and fauna. There are many unique endemic plant species on Rēkohu, some of which are now commonly used garden plants in Aotearoa such as the Chatham Island Forget-me-not (Myosotidium hortensia). As plant nerds we were keen to see these plants in their wild habitat - several day trips to investigate ensued:
Ohira Bay basalt columns
Our first excursion was to the famed basalt columns in the northwest of the island and they did not disappoint! Formed from a lava flow during the Cretaceous period 80 million years ago the polygonal shapes occurred as the lava cooled. The stone was used by Moriori for tool making and the pentagonal shape has become one of the symbols of the Chathams.
Tucked into the niches between the rocks is a diverse community of native plants which are adapted to the minimal soil and coastal exposure. Specific plants we observed included the native ice plant (Disphyma papillatum), Chatham Island spleenwort (Asplenium chathamense), sand daphne (Pimelia arenaria), and remuremu (Selliera radicans).
The plant communities observed here were a great lesson that plants will grow in severe environments - provided you select the ones adapted to those conditions.
Admiral Gardens
After visiting the basalt columns we dropped into the nearby Admiral Gardens. Owners Lois and Val Croon have created a diverse and exciting garden from what was previously a bare farm paddock. The first priority was to create shelter. Using both exotics - macrocarpa and pine - and the native hakapiri (Olearia traversii), a buffer to the wind was created which then enabled the more detailed planting to flourish. The garden has a temperate climate with very little frost which allows for a subtropical mix of plants - both native and exotic.
Plants of note that we spotted included the local ribbonwood (Plagianthus chathamicus), a subspecies of the mainland Plagianthus regius which has much larger leaves and lacks the divaricating growth form in its juvenile stage. The lack of juvenile divarication is also a feature of the local lancewood tree (Pseudopanax chathamicus) - perhaps due to the lack of browsing Moa in the long past.
Several of the gardens namesake - the admiral butterfly - were spotted out and about enjoying the garden.
Manauea / Ocean Mail Scenic Reserve
On a trip to the north of Rēkohu we dropped into look at the plant communities within the wetland at Manauea. The wetland is formed on undulating peat soils on the edge of Te Whanga Lagoon - the large inland water body on Rēkohu. A fire in 1994 burnt much of the plant communities there but it has since recovered well.
The local restio, Chatham Island bamboo rush (Sporadanthus traversii) is the primary peat former and creates large domes within the wetland. The golden inflorescence of the Sporadanthus was a dramatic feature. Other key species within the patchwork of plants included harakeke (Phormium tenax ‘Chathams’), Dracophyllum scoparium, Oioi (Apodasmia similis), and bracken ferns. Other plants dotted through included taramea karupuru (Aciphylla traversii), hokotaka (Corokia macrocarpa), Chatham Island mingimingi (Leucopogon parviflorus) and pouteretere (Leptecophylla robusta).
The contrasting textures, forms and colour created a visually exciting and cohesive landscape.
Henga Scenic Reserve
The initial walk is through gnarled kopi / karaka (Cornycarpus laviegatus) forest with a beautiful understory of lush kawakawa (Piper excelsum). The track then emerges into the open at a lookout with views over the western coastline down to a surprisingly tropical looking beach and outcrops of wind hewn limestone. The area is known as Henga Bluff and is sacred to both Moriori and Māori. At the lookout we found our longed for ‘wild’ Chatham Island Forget-me-nots looking luscious and leafy in the wind blown landscape. We suspect this patch at the lookout was planted rather than naturally occurring but we claimed it as a find.
The plant communities on the dunes sloping down to the beach was fascinating. The open low shrubland was made up of scattered wind sculptured hokotaka (Corokia macrocarpa) set into a matrix of wiwi (Ficinia nodosa), tātaraheke (Coprosma acerosa), and sand daphne (Pimelia arenaria). The broad leaves and spiky flower stalks of Chatham Island flax (Phormium tenax ‘Chathams’) were dotted through as an emergent form. Towards the beach patches of Chatham Island Geranium (Geranium traversii) were growing strongly out of the sand. Lots of inspiration!
From a design perspective both the Ocean Mail wetland and Henga Reserve coastline were a good reminder of how complex biodiverse landscapes often still have a cohesive visual appearance which is created by the regularity of the dominant species, their contrasting foliage and forms. Set within these more obvious species, the ‘finer grain’ less obvious plants find their subtle niches.
Manukau Nursery, Owenga
Just down the road from where we were staying in Owenga was Manukau Nursery. The nursery’s goal is to ‘bring back the birds’ on the adjacent coastal farm by propagating and planting 150,000 native trees between 2023 - 2026. Lucky for us we had already met Tiffany McClunie who works there and she offered to show us around. It was fascinating to see the range of plants being grown and the rare species being propagated. The revegetation project is being undertaken in two stages - an initial planting of primarily Chatham Island akeake (Olearia traversii) trees and Harakeke (Phormium tenax) is undertaken to establish a shelter crop, followed by a succession planting of more diverse species that benefit from the established shelter.
We particularly enjoyed seeing the rare Chatham Island Button Daisy (Leptinella featherstonii) in propagation - a ‘mega-herb’ variety of Leptinella - which grows into a leafy shrub instead of the ground hugging species we commonly see in NZ gardens. Tiffany noted that L. featherstonii needed bird guano to do best. Its current wild distribution is essentially limited to smaller offshore islands inhabited by seabirds.
A week on Rēkohu was long enough to whet our appetite, and hopefully we will get back there again to explore the islands special flora in more detail. A big hello and thanks to all the Chatham Islanders who we met and made us feel so welcome.
Soaking up the landscape at Henga Scenic Reserve
