Ōtari-Wilton's Bush is a native botanic garden and forest reserve located in the suburb of Wilton in Wellington, New Zealand. It is New Zealand's only public botanic garden dedicated solely to the native plants of New Zealand. The reserve includes of native forest, and of plant collections. The first section of what would become Ōtari-Wilton's Bush was purchased in 1906 by the government and designated as a scenic reserve. The first director of the reserve was botanist Leonard Cockayne, who alongside John Gretton Mackenzie established the Ōtari Open-Air Native Plant Museum in 1926. The forest in the reserve contains some of the oldest trees in Wellington, including an 800-year-old rimu. The reserve holds a broad range of plants, with one bioblitz recording nearly 500 species of vascular plants, liverworts, mosses and lichens. In addition to its extensive flora, the reserve also hosts a wide range of fauna, including notable species such as ornate skink (Oligosoma ornatum), longfin eel (Anguilla dieffenbachii) and glowworm (Arachnocampa luminosa). The reserve undergoes regular pest control to minimise the effects of invasive species such as possums and rats. Due to its diverse plant collection and reserve biodiversity, scientific research is regularly conducted at Ōtari-Wilton. Ōtari-Wilton's Bush is owned and managed by Wellington City Council and is supported by the Ōtari-Wilton's Bush Trust.
History
The original forest in the area surrounding Ōtari-Wilton's Bush was a podocarp broadleaf forest. The area was known and used by successive iwi as a good place to gather food and catch prey, and this gives rise to the Māori name ('place of snares to trap kākā') shortened to . Large trees in the wider area were felled for timber when European settlers arrived in the region, and farms were established.
In 1847 the Ōtari Native Reserve was a block of unsurveyed land between Kaiwharawhara and the Makara valley that was set aside to enable the Crown to offer land swaps to local Māori in exchange for pā sites at Kaiwharawhara, Ōwhāriu and Pipitea. From the 1850s there was a rapid decline in the Māori population in Wellington.
Settler Job Wilton arrived in Wellington in 1841 as a seven-year-old boy. He married Ellen Curtis in Wellington in 1860, and they purchased in the Kaiwharawhara valley. Wilton had been concerned about the large-scale land clearance around Wellington in the 1840s and 50s and the loss of native forest. He set aside of untouched forest near his homestead, and fenced it to protect it from stock. This became known as Wilton's Bush, and was a popular area for picnickers and day trippers.
In 1902, the Māori owners of a block of native forest in the Ōtari Native Reserve wished to lease their land, and this raised concerns that the forest would be cleared. A deputation including Job Wilton, two mayors, and three members of Parliament met with the Minister of Lands to ask for steps to preserve the land for the benefit of the public. The New Zealand Times supported the proposal, describing Wilton's Bush as:
In 1906 the government bought of land in the Ōtari Native Reserve from its Māori owners and designated it as a scenic reserve, naming it Ōtari-Wilton's Bush Scenic Reserve. The land was later transferred to Wellington City Council in 1918 for "recreation purposes and for the preservation of native flora". In 1918, John Gretton Mackenzie was appointed as the new Director of Parks and Reserves for Wellington. When Mackenzie commenced in October that year, he immediately put a stop to cattle grazing in the reserve, noting that grazing removes undergrowth and allows wind to pass through the forest. By 1920, new paths had been created through the reserve.
Ōtari Open-Air Native Plant Museum By 1926, the site was known as the Ōtari Open-Air Native Plant Museum. The first director of the reserve was Leonard Cockayne. In 1926 he worked with John Gretton Mackenzie on plans for the open-air plant museum. Mackenzie was a keen supporter of a proposal put forward at a meeting of the New Zealand Institute of Horticulture in March 1926 to create a native plant museum. In June 1926, Mackenzie and Cockayne, who was honorary botanist to the institute, prepared a report to the Wellington City Council for the development of an open-air native plant museum at Ōtari. Cockayne's report stated:The object of this scheme is to present a vivid picture of the plant-life of New Zealand—so different from that of any other country—and the species of which it is composed, together with the use of such for the adornment of gardens. If carried out [...] there would be in the city of Wellington an open-air museum the like of which has never been attempted before, not only in this country but in any part of the world. [...] Each species would be accurately labelled with its name, its habitat, and its distribution in New Zealand. There would also be grown the various hybrids and varieties of the species. Thus the whole flora of New Zealand could be seen at a glance, as it were, and the plants could be admired and studied in detail.Cockayne formed a rough plan for how the reserve should be structured, focusing on four key aspects that encapsulate plant life in New Zealand:
Create a collection with every native plant species in New Zealand, with the species ordered by family and genus. Recreate representative ecosystems of notable flora groups, such as subalpine scrub, coastal thickets and kauri groves. Use plantings to demonstrate how native plants can be utilised in gardens. Restoring the forest remnant to its natural state.
In 1928, the eminent botanist Arthur William Hill, director of the Royal Botanic Gardens, Kew, visited Ōtari while on a trip to New Zealand and even went on botanical trips with Cockayne. The Troup Picnic area adjacent to the Kaiwharawhara Stream was named in honour of George Troup, a distinguished architect and 23rd Mayor of Wellington.
1991 to present The name of the reserve was changed to Ōtari Native Botanic Garden in 1991, then Ōtari-Wilton's Bush Native Botanic Garden and Forest Reserve in 1999, before finally being renamed Ōtari-Wilton's Bush in 2000, recognising the influences of both Māori and Europeans.
From 1997 to 1999, improvements were made to visitor facilities and access around the gardens, with the objective of Ōtari becoming a visitor attraction. A tree-top canopy walkway was constructed over a stream gully, linking the car park and information centre with the Cockayne Lawn and gardens to the west. The bridge improved the connection between the information centre and collections, and avoided visitors having to walk along Wilton Road to visit these areas. The redevelopment also included a new alpine rock garden with a small tarn, and new visitor facilities at the information centre. A (gateway) carved by Bryce Manukonga was installed at the entrance. The redevelopment project was funded by a $1.2 million grant from the Plimmer Bequest, with an additional $300,000 from Wellington City Council. The redeveloped facilities and information centre were officially opened at dawn on 9 October 1999. By 2005, there were around 95,000 visitors to Ōtari-Wilton's Bush each year.
A track alongside the Kaiwharawhara Stream had been cleared for the upgrading of a sewer line in 1991, but by 2000 the section upstream from the Troup Picnic area had become almost impassable because of the growth of blackberry and weeds. In the early 2000s, the Otari-Wilton's Bush Care Group began clearing the track and planted over 20,000 native plants alongside the stream to revegetate the area and restore the environment. In 2004, Wellington City Council purchased a block of Ministry of Education land below Ōtari School to add to Ōtari-Wilton's Bush. The pine trees on the land were removed and replaced with natives.
Forest reserve
The forest at Ōtari-Wilton's Bush covers around of the catchment area of the northeast flowing Kaiwharawhara Stream. The area includes several gullies and side streams, some with small waterfalls, and is surrounded by hills up to above sea level. The underlying rock is greywacke, and the vegetation includes original podocarp broadleaf forest, semi-coastal kohekohe (Didymocheton spectabilis) forest and regenerating forest and scrub. Larger trees in the forest include podocarps such as mataī (Prumnopitys taxifolia), miro (Pectinopitys ferruginea), tōtara (Podocarpus totara) and rimu (Dacrydium cupressinum). The forest contains some of the oldest trees in Wellington, examples of which can be seen from the canopy walkway. One notable example of these trees is an 800-year-old rimu named "Moko". The tree is around high, wide and has a crown spread of . At the base of the tree is a platform that was constructed in 2019 to protect the tree and enable viewing by visitors. The larger trees will often have perching plants (epiphytes) in higher branches. Climbing plants are also common throughout, including supplejack (Ripogonum scandens), New Zealand passionfruit (Passiflora tetrandra), and several species of rātā (Metrosideros). On the upper slopes, the predominant trees are māhoe (Melicytus ramiflorus), rewarewa (Knightia excelsa), tawa (Beilschmiedia tawa) and kohekohe, with some forest remnants of mataī and rimu. In damp areas, there are pukatea (Laurelia novae-zelandiae) that typically have large plank buttress roots to support their growth.
The high south-facing slopes in the reserve are covered in regenerating scrub that is dominated by introduced plants such as gorse (Ulex europaeus) and Darwin's barberry (Berberis darwinii), although native plants such as rangiora (Brachyglottis repanda) and māhoe can also be found.
In 2007, a BioBlitz was held to "increase public awareness and to generate scientific knowledge" of the biodiversity within Ōtari-Wilton's Bush in celebration of its one hundred year anniversary. Nearly 500 species of vascular plants, liverworts, mosses and lichens were recorded during the 24 hours of the BioBlitz including a number of new records, such as the flowering plant Veronica javanica and the liverwort Marchantia polymorpha subsp. ruderalis.
Pest control Possums were introduced to the Wellington region in the 1880s and have since devastated the environment by feeding on native plants and animals. In 1928, Leonard Cockayne began a possum control program at Ōtari-Wilton to limit their impact. This program continued for decades, but in the 1990s it was determined that there were still twelve possums per hectare in the reserve. In response to this, the Greater Wellington Regional Council began intensively poisoning possums with cyanide traps in 1993, killing over 800 of them. After this, hockey-stick bait stations filled with poison were installed throughout the reserve and possums are now rarely seen. Other mammalian pests such as rats and mustelids are also targeted with traps. To combat these pests, the Ōtari-Wilton's Bush Trust was gifted DOC200 predator traps, which were laid out through areas of the reserve and are maintained by volunteers.
Native botanic gardens
Ōtari-Wilton's Bush is the only public botanic garden in New Zealand that is entirely dedicated to native plants. The collections contain about 1,200 species, including hybrids and cultivars representing plants from mainland New Zealand and off-shore islands. The plants on display have generally been raised from seeds or cuttings collected from their original environments. The four main objectives of the collection are: Conservation: raise seedlings of threatened species, either to be kept in the gardens for conservation purposes, or for use in plant recovery programmes in the wild. Research: enable scientific study of the plant collections for plant ecology, classification and economic potential. Education: help visitors learn about plant names and characteristics, including providing labelling.