Latest news with #JustinMorgenroth
Otago Daily Times
16-07-2025
- General
- Otago Daily Times
Selwyn plans big increase in tree planting
Selwyn is considering a policy of 'replacing one tree with at least two' after Rolleston was shown to have one of the lowest numbers for a town in New Zealand. The policy was discussed at the Climate Change and Sustainability Subcommittee Meeting on July 9, a week after a study was released by the University of Canterbury's School of Forestry, led by Professor Justin Morgenroth and Dr Ning Ye. It showed Rolleston's tree canopy cover was 7.9%, ranking it 77 out of 78 cities and towns in the study. Other Canterbury towns didn't fare much better, with Christchurch – the Garden City - at 13.6% (57th), Kaiapoi at 11.8% (66th), Ashburton at 11.5% (69th), and Rangiora at 9.5% (74th). Picton was on top at 59% while Hāwera was below Rolleston at 7.5%. At the subcommittee meeting, Selwyn's people, culture, and capability executive director Steve Giblin,g said the council is 'looking for better direction around how we proactively manage trees, especially in a fast-paced growth district like ours'. The said trees play a key role 'in cooling through shade, providing habitat for biodiversity, and also managing storm water'. Rolleston and its other rapidly growing urban centres have seen trees and shelter belts removed to make way for subdivisions. Those developments have included new trees, but they take time to establish. The council want to improve how they plan and consider trees, both new and existing. It was noted that there are five trees being removed for the Lincoln town centre redevelopment, but 50 trees will be planted in their place, with special strata vaults to avoid root issues, which is something the policy will cover. Strategy team leader Ben Baird said the approach to developing a policy was to recognise the value of trees, 'especially in our infrastructure and our subdivision work'. 'Having a goal of replacing one [tree] with at least two, and kind of looking to improve our canopy cover.' The council consulted the community on trees last year and Baird summarised the feedback as people wanting to see more trees, the council needs to be doing more to maintain them, and removal should be a last resort. He said staff would present on the draft tree policy in August. Professor Morgenroth believes it's worth investing in trees. 'Research has shown that for every $1 invested in urban trees, trees will return $3.40 in benefits. 'The benefits include, but are not limited to, carbon sequestration/storage, air pollution removal, stormwater runoff mitigation, energy reduction (shade/shelter), and aesthetic value.' There are other unquantifiable benefits, such as human physical and mental health, as well as biodiversity, he said. 'Increasing canopy cover will require planting, but that will take time. 'Limiting the removal of existing healthy trees is also a means of increasing canopy cover through growth of existing trees, or at least not reducing cover. 'Tree protection regulation is limited in New Zealand to individual trees listed in district plans, so regulatory approaches - unless they are changed - for retaining existing trees aren't likely to make a large contribution to maintaining or increasing canopy cover.' By Jonathan Leask, Local Democracy Reporter
Scoop
11-07-2025
- General
- Scoop
Selwyn Plans Big Increase In Tree Planting
Selwyn is considering a policy of 'replacing one tree with at least two' after Rolleston was shown to have one of the lowest numbers for a town in the country. The policy was discussed at the Climate Change and Sustainability Subcommittee Meeting on July 9, a week after a study was released by the University of Canterbury's School of Forestry, led by Professor Justin Morgenroth and Dr Ning Ye. It showed Rolleston's tree canopy cover was 7.9%, ranking it 77 out of 78 cities and towns in the study. Other Canterbury towns didn't fare much better, with Christchurch – the Garden City - at 13.6% (57th), Kaiapoi at 11.8% (66th), Ashburton at 11.5% (69th), and Rangiora at 9.5% (74th). Picton was on top at 59% while Hāwera was below Rolleston at 7.5%. At the subcommittee meeting, Selwyn's people, culture, and capability executive director Steve Gibling said the council is 'looking for better direction around how we proactively manage trees, especially in a fast-paced growth district like ours'. The said trees play a key role 'in cooling through shade, providing habitat for biodiversity, and also managing storm water'. Rolleston and its other rapidly growing urban centres have seen trees and shelter belts removed to make way for subdivisions. Those developments have included new trees, but they take time to establish. The council want to improve how they plan and consider trees, both new and existing. It was noted that there are five trees being removed for the Lincoln town centre redevelopment, but 50 trees will be planted in their place, with special strata vaults to avoid root issues, which is something the policy will cover. Strategy team leader Ben Baird said the approach to developing a policy was to recognise the value of trees, 'especially in our infrastructure and our subdivision work'. 'Having a goal of replacing one [tree] with at least two, and kind of looking to improve our canopy cover.' The council consulted the community on trees last year and Baird summarised the feedback as people wanting to see more trees, the council needs to be doing more to maintain them, and removal should be a last resort. He said staff would present on the draft tree policy in August. Professor Morgenroth believes it's worth investing in trees. 'Research has shown that for every $1 invested in urban trees, trees will return $3.40 in benefits. 'The benefits include, but are not limited to, carbon sequestration/storage, air pollution removal, stormwater runoff mitigation, energy reduction (shade/shelter), and aesthetic value.' There are other unquantifiable benefits, such as human physical and mental health, as well as biodiversity, he said. 'Increasing canopy cover will require planting, but that will take time. 'Limiting the removal of existing healthy trees is also a means of increasing canopy cover through growth of existing trees, or at least not reducing cover. 'Tree protection regulation is limited in New Zealand to individual trees listed in district plans, so regulatory approaches - unless they are changed - for retaining existing trees aren't likely to make a large contribution to maintaining or increasing canopy cover.'
Scoop
01-07-2025
- Science
- Scoop
Tree Cover For Kiwi Towns And Cities Spotlit In New Study
How leafy is your hometown? Researchers from Te Whare Wānanga o Waitaha | University of Canterbury (UC) have the answer after completing urban tree canopy cover assessments for 75 towns and cities across Aotearoa New Zealand. Led by Professor Justin Morgenroth and Dr Ning Ye from the UC School of Forestry, the project team used aerial imagery and LiDAR (light detection and radar) data to assess how much land area is covered by tree canopy. Te Uru Rākau New Zealand Forest Service provided funding to support a team of UC student interns; Maggie Crawford, Jean Morton, Tuawhio Porima and Stephen Thompson, to help carry out the work. The results show that urban tree canopy cover across the 75 towns and cities ranges from 7.5% in Hāwera to nearly 59% in Picton, highlighting significant variation and the potential for future planting. The average across all towns and cities was 19%. The findings have been used to create customised reports for local councils across the country, detailing forest cover within their urban boundaries. 'Urban tree canopy— the layer of leaves, needles, and branches that cover the ground when viewed from above—plays a vital role in the health, sustainability, and resilience of our towns and cities,' Professor Morgenroth says. 'It provides many benefits, including climate change mitigation, reducing air pollution, improving water quality and providing habitat for wildlife. 'Research has shown that for every $1 invested in urban trees, trees will return $3.40 in benefits. We hope this work will spark conversations within councils and communities about how to protect, grow, and plan for more trees in cities.' The reports outline how each council can build on the findings, such as setting canopy targets, conducting neighbourhood-level mapping, and engaging with schools or community groups in greening efforts. Urban tree canopy cover in Auckland, Wellington and Christchurch, has previously been mapped using a different method, with Wellington having the highest canopy cover at 31%, followed by Auckland at 18% and Christchurch with 14%. Professor Morgenroth says the differences in canopy cover between the various towns and cities can be the result of population, climate, development history, and surrounding land uses.
