Chris McAulay, Manager – Parks Operations, Invercargill City Council, New Zealand
Walking down tree-lined Coronation Avenue in Queens Park’s today, you’d be forgiven for forgetting the sheer scale of devastation suffered by the park only not that long ago. Invercargill’s award-winning public gardens felt the full force of Southland’s big storm on 23 October 2025, with wind gusts exceeding 130 km/h batter the city in a dramatic reversal of the calm spring conditions earlier that day.
Although the most extreme winds lasted less than an hour, damage across the city was widespread. Thousands of people were left without access to critical infrastructure, including electricity and telecommunications, and a state of emergency was declared throughout Southland.
Queens Park, containing some of Invercargill’s oldest and largest public trees, was hit particularly hard when the winds barrelled in. Many trees were uprooted, and then toppled, throughout the 81-hectare park, while many of those left standing suffered significant structural damage.
By the time the state of emergency was lifted on 7 November, more than two weeks after the storm, hundreds of trees had fallen and green spaces across Invercargill remained off limits to the public due to the risk of falling trees, branches and debris.
For possibly the first time in its 170-year history, Queens Park was closed.
Our response
The initial response to the storm focused on damage to essential infrastructure and immediate public safety risks, such as broken traffic lights, dangerous structures and trees blocking roads. While this immediate response was relatively swift, early assessments of parks and reserves suggested it would take at least five or six months to repair damage to the tree canopy and make these public spaces safe again.
It was clear from the scale of the damage that a significant portion of the remedial work would exceed our in-house capability. Trees needed to be checked for broken and damaged limbs, typically by climbing and inspecting each individual tree. This required specialist arboricultural skills and equipment.
In Queens Park, we focused on retaining heritage canopy cover and saving trees wherever possible. In particular, retention of the century-old English beech trees lining Coronation Avenue, with their obvious community and amenity value, was seen as essential to preserving the character of the park. Some of these trees were pollarded and others had metal braces installed to ensure their continued structural integrity. Although these measures have a significant visual impact in the short term, they have allowed the trees to be retained, giving them a chance to regenerate, and maintaining key canopy cover in the park.
Queens Park remained closed for approximately a month following the storm, with a staged reopening from mid-November, balancing public safety with the sheer volume of work required. Much of the space opened at the beginning of 2026, with only isolated sections of trees needing remediation remaining.
The total cost of cleaning up fallen trees and other damage across Council’s 150-odd parks and reserves – including Queens Park – exceeded NZD900,000. More than 630 trees were climbed and pruned by arborists and nearly 800 trees were removed across the city, creating approximately 1,200 tonnes of excess wood and saleable logs, and mountains of mulched woodchips.
Lessons learned
The importance of maintaining a healthy tree network across our city was brought sharply into focus following the storm.
We already knew that stable and well-established trees could suffer damage during extreme weather. However, the scale of damage caused by the high winds experienced in October’s storm was a particularly harsh reminder of what nature could do to our public spaces and the risk this damage could pose to the community. It was not the only setback weathered by Queens Park that year. Strong winds earlier in June saw a mature pine tree fall, while seven trees toppled in adverse weather in September, including a large oak believed to be about 80 years old.
Saturated ground due to heavy rainfall may have contributed to the number of trees falling. There was some speculation in the community that trees in Queens Park were problematically shallow-rooted due to historic planting methods, namely using biscuit tins to raise saplings.
Invercargill’s soils are categorised primarily as peat and waterlogged gley soil,1 which naturally limits potential root depth. We did not find any evidence, however, that shallow rooting caused trees to fall, including trees planted many decades ago. Regardless, the storm events were a clear example of what could occur as a changing climate drives increasingly unpredictable weather patterns in our region. It is clear that the damaged and fallen trees, assessed as safe under normal conditions, were not as resilient as they could have been in such extreme weather.
More storms and summer droughts will only add to the pressures on our tree network, which could lead to greater losses and greater danger to the public in the future.
Looking forward with a plan
Having a good understanding of the existing tree network is a key part of ensuring that trees in our public spaces remain safe and maintenance is prioritised where it is needed.
Trees clearly provide a range of benefits, such as shade and aesthetic value, but the damage sustained last year showed some of the real hazards that they can present when put under extreme stress. By managing the urban forest appropriately, we can build resilience in our canopy and ensure we have the right tree in the right place for the right purpose.
Since 2020, following the development of our first tree plan, we have captured data on approximately 15,000 high-risk trees across the city, using human-based methods to capture basic information.
Over the past couple of years, we have improved data collection in specific parks, including Queens Park, using a specialised technology platform, greehill, in partnership with Treetech. The greehill platform captures highly accurate 3D data of tree structure and canopy using Light Detection and Ranging (LiDAR), and AI processes this data to automatically identify, measure and assess trees. This technology enables efficient, large-scale tree management and monitoring and will give us a better understanding of the heights, ages and species of trees in the urban forest network, as well as their carbon sequestration capabilities. These data are invaluable for the safety of the public and to protect and nurture the living assets in our parks.
We are currently in the process of refreshing our tree plan, which will help further guide our approach to managing trees in Queens Park and the city. One of the goals in the new plan is a preference for at least 30% native species when planting on reserve land.
As large, fast-growing trees, most of the city’s shelter plantings are made up of exotic eucalyptus, Monterey Cypress Hesperocyparis macrocarpa and pine species. In October’s storm, and the weather events earlier in 2025, these three tree types were the most affected, with only a small number of New Zealand natives impacted.
Although natives have not been used as widely as specimen trees or shelter in our parks historically, and there are fewer mature native trees that could be damaged, it is clear that they perform better in our environment in some situations and can potentially have a longer life in the right location.
Having a clear tree plan, which incorporates a native species goal, ensures that we consider the best trees for a given area, even if they are not the exotic species traditionally used in our urban parks. As we expand the data we have on our trees, we can increasingly use a robust evidence-based approach to determine what species we plant where.
October’s storm showed us how vulnerable our city can be to extreme weather and how important it is to plan for uncertainty in the future. While trees can present risks during severe weather events, their benefits far outweigh those challenges when they are well-planned and managed.
We don’t know what the future will bring, or what storms Queens Park will have to weather in a changing climate. Learning from how our trees respond in an event like Southland’s big storm is the first step towards a diverse and resilient tree network that enhances our urban environment and can be a legacy for the future.
(1. See https://soils.landcareresearch.co.nz/topics/soil-classification/nzsc/soil-orders/gley-soils for more information on this type of soil.)
Read Part 1 of our Resilient Gardens Series here: Resilient Gardens – A Conversation with Sue McDougall.
Read more about Resilient Gardens in Issue 66 of the BOTANIC GARDENer Magazine.
