Feature

Getting It Right For Climate Change

In the previous issue, we looked at climate change and how scientists are testing different plants in simulated drought and heatwave conditions.

This month we look at the Dubbo’s Heat Island Amelioration Project.

Solutions to keeping cities cool will involve not only choosing the right plants but in many cases enhancing growing conditions beneath the surface.

In the past, street tree planting methodology has often been based on digging a hole into the sub-base of the road, planting the tree, and then having the unrealistic expectation that the tree will thrive and persist long term in this environment. The result being that many trees planted decades ago are now in poor health and serious decline.

Such was the case in Dubbo NSW when the Regional Council (DRC), in 2015, took the plunge and removed failing trees in its Street Tree Masterplan to trial the Stockholm Method of planting. Dubbo’s Heat Island Amelioration Project will lower street surface temperatures by up to 20 degrees and recently won the Council a top award at the 2019 Local Government NSW Excellence in the Environment Awards. Ian McAlister, who led the project from planning to completion, said the new landscape, overwhelmingly, has the approval of the Dubbo community.

“My expectation is that any methodology that provides a tree with sufficient room for root extension – and a growing medium to provide support and moisture and nutrient holding capacity – will ultimately produce a better performing longer lived tree for our urban environments,” said Ian.

“Our first Stockholm Method plantings were undertaken as part of the Darling Street Beautification project. We used only two tree species – the endemic Angophora floribunda (Rough-barked Apple) and Agathis robusta (Kauri Pine). Both of these tree species are performing exceptionally well, reinforcing the importance of improving the planting conditions of the trees if you want them to thrive in the urban environment.

“This project had a multifaceted approach and considerable cost efficiencies were achieved. It involved the upgrading of the stormwater system in this area, replacement of potable water mains, and improving the connectivity of the City’s cycleway and pedestrian walkway. The Stockholm Method (modified) is comparatively quick to install and low in resource demand.

“For Dubbo, it was extremely cost effective as we used waste rock generated from a sub-division, and compost that we produced at our own facility. The biochar is generally the only external material that we purchase.

“The rock matrix, when securely locked together, resists subsidence in roadways even under heavy loads and the biochar has extremely good moisture holding capacity. This is extremely important in the hotter climes of Australia as it reduces moisture stress on the trees and, even if you require to provide supplementary water, reduces the watering frequency and thus costs.

“The Stockholm Method (modified) to date appears to be an extremely sound planting method. One of the things that I really like about it is the flexibility it offers in terms of adding additional unplanned underground services. It allows for the rock matrix to be excavated, being careful of the tree protection zones. New services can then be laid and the rock matrix replaced allowing for continued, uninterrupted root growth through the vault. Other systems are not quite so flexible but this can be overcome, to some extent, at installation stage through the addition of spare conduits through the vault.

“The major way that I see climate change impacting on the arboricultural industry will be through the tree species selection for our urban areas. As our climate becomes hotter and drier, the rainfall more erratic, and higher intensity storms, the tree species that we use will need to shift to survive and thrive in these changing environmental conditions. This issue will potentially impact all areas of the arboricultural industry. As a professional industry we need to be taking the lead in assisting in the identification of what trees will be suitable for planting into the future for specific regions of Australia.”

Ian said the Stockholm Method – modified or otherwise – is an effective tree planting system that can be used to improve tree planting success throughout Australia.

The three components – rock (250mm – 300mm), biochar and compost/ soil mix are blended off site and then brought in as required. The pits are excavated using a backhoe, then lined with a geotech fabric before the blended material is installed in layers of approximately 300mm.

Between layers a small robotic mini vibrating roller is dropped into the pit. The vibrating roller helps to ensure that the rock matrix is firmly locked together, and the vibrating action helps to fill the voids with biochar/soil/compost between the rocks.

The geofabric is then brought across the top of the rock matrix. This geofabric helps to reduce root penetration into the road base.

The subgrade of the road can then be built to normal specifications across the top of the root vault.

Depending on where the pit is within the streetscape an open-ended concrete vault is installed on top of the rock matrix and backfilled with the rock matrix. This serves a number of purposes – it prevents asphalting against the trunk of the tree, provides additional water / air exchange, allows easy access for supplementary watering to occur in drought / dry conditions and provides the opportunity to install a decorative grate to further enhance the streetscape.

May 19, 2020 / by / in ,
Transform Waste Wood

With the cost of disposing of wood increasing, the opportunity to process tree waste into saleable split timber has huge potential to create a valuable revenue stream.

Whitlands Engineering is the only name you need to know when it comes to firewood processing – designing and manufacturing Australia’s most trusted brands – Superaxe, and Rex. Australian owned and Australian made, Whitlands Engineering has earned its reputation as a leader in the industry. CEO David Burder says: “We’ve been providing machines to the farm forestry sector and arbour industry for over 20 years – the durability, ease of use and productivity of all our machines means they are the first choice for many companies seeking to exploit the profit potential in tree waste and plantation timber”.

The range of machinery covers all bases. The Superaxe wood splitter range suits farm and small commercial operations, while the Rex range provides solutions to bulk and industrial firewood processing. The Rex Firewood Processor range and the Rex Log Saw range are the result of many years’ research and development and have been met with industry acclaim. A range of wood cleaning trommels, infeed hoppers and outfeed elevators rounds out the range, providing options for wood handling requirements.

For businesses looking to invest, two key factors in machinery selection are:

Safety: The safety of machinery operators is critical. The key issue for the arbor industry is that if an employee uses a non-compliant machine and injures themselves, it is the company that is most likely liable, not the manufacturer. The same applies for machines which have been tampered with. In which case the company can be fined for owning a tampered machine even if there is no actual injury. Both Superaxe and Rex ranges are WorkCover compliant and have set benchmark standards across the industry when it comes to ensuring operator safety.

Output Efficiency: Mulching excess timber may be quick but the sale price is low compared to split timber. The key for business then is to maximise output and minimise labour in order to generate a profitable return on investment. The Superaxe WS3150 has an estimated output (from blocked timber to split firewood) of 4 cubic meters an hour. The larger Rex 600X can manage 10 cubic meters an hour with two operators. Both of these machines are road towable, compact and reliable, making them top options for processing blocks into split timber on site.

So, for arbour operators looking to develop additional revenue streams, the Whitlands Engineering range of wood splitters and processors is definitely the ideal place to get started.

For more information visit www.superaxe.com.au.

April 23, 2020 / by / in , ,
Tree Habitat Hollow Creation Programme

Never like today Australia needs to focus on protecting and preserving its wildlife and diversity of animal species.

A pilot Tree Habitat Hollow Creation Programme started in Queensland in 2015, thanks to the joined effort of Local Government and Habi-Tec. A few years into it, not only success rates are exceeding expectations, but the whole community has come on board.

The Gold Coast Tree Habitat Hollow Creation Programme began as a pilot programme in 2015. It began by a chance site meeting between UK climbing arborist Steve Collom and I pruning a big old Euc tereticornis. Steve introduced himself and we discussed our shared interest and passion for arboreal habitat trees and urban Eucalypts. Steve carried a box of coring drills and a CCTV eel to explore tree cavities during his working day, just for the love of it. I was immediately struck by his knowledge and love for wildlife and knew I wanted to work with him.

Both Steve and I discussed habitat loss and ethical pruning, the movement beyond the Australian Standards, excessive deadwooding for hazard risk, and over-pruning generally. Following some early conceptual work, we began on an ideally located and prominent Eucalyptus grandis in Currumbin, and the programme was born.

I was able to target hardwood trees that fit the criteria in form, volume, and location. We also targeted for habitat creation those occasional Eucs allegedly poisoned by an adjacent resident. This is a notable win in terms of strategy and for lack of any real recourse against offenders in legal terms or within policy. A nice tree blocking your view might not seem so bad when instead you end up staring at a hatstand full of critters and noisy birds.

Each inherently unique tree offered opportunities to create an array of artificial hollows with the most favourable features, configuration, dimensions and protection against predators, to be ideally habitable for their intended recipients. We were spoiled for choice in many ways with tree after tree lending itself to the cause.

Through a slow-burn operation Steve and the Habi-Tec crew (partners Ash Sandercombe and brother Dan Collom), developed a wealth of expertise in creating artificial arboreal habitat hollows, while

I captured hearts and minds within the organisation and private industry, working to ensure the programme was understood and supported by the those within the broader fields of arboriculture, ecology, natural areas, urban design, town planning, and even developers.

In hindsight the programme took on a momentum and life of its own. It wasn’t until we completed about a dozen trees that we began to realise the scope for the practice to be extended further beyond the established urban areas of the Gold Coast and into the natural areas and surrounding new estates in the ‘northern growth corridor’ towards Brisbane.

The City of Gold Coast spans 1,300km² and our urban tree population exceeds 800,000 in public open space, with no shortage of potential candidates we could retain and activate. In context of the wider region the programme seemed like only a small gesture to our native wildlife as an offset, but like a ripple in a pond, the impacts spread far and wide.

At the programme’s two year mark we began auditing the early trees we created via aerial inspection, with Habi-Tec capturing data with CCTV, fixed motion-activated wildlife cameras, and visual inspection of the artificial hollows for evidence of activity to determine which species of birds or wildlife had taken up residence.

Not surprisingly the iconic Rainbow Lorikeets were most prolific, having made homes within most trees in several hollows, but we also documented uptake widely by squirrel gliders, galahs, cockatoos, corellas, possums, wood ducks, and in some of the pipes we installed the micro-bats were moving in too. The Habi-Tec team have also taken initiatives in transplanting native beehives delicately into new pipes and cavities.

The more trees we audited the more our expectations of success rates were exceeded and this only spurred us on.

Only isolated trees outside of connective corridors showed low rates of uptake but still had some activity. In the more wooded areas like Robina a big old Euc pilularis we created had corellas literally moving in as the crew packed up their equipment on the day. These critters are desperate for housing and we were building wildlife high rises to rival the famous Q1 in Surfers Paradise!

Steve, Ash and Dan were developing a deeper understanding of success and failure rates in whole trees and individual hollows. I learned that the community and City tree officers were more than receptive to the cause and we gained more and more participation from residents in monitoring and reporting on wildlife movements.

“This was a success in human terms, educating those who’ll inherit the earth in the science of biodiversity, and awareness of their natural surrounds.”

Adjacent residents received a Habi-Tec brochure in their letterboxes and would phone Steve’s better half Louella and gleefully report their kids enthusiasm for this newly built wildlife hotel in the park next door. This was a success in human terms, educating those who’ll inherit the earth in the science of biodiversity, and awareness of their natural surrounds.

Each tree is fixed with a plaque that designates the tree as habitat and warning against access, alteration or disturbance. There are 71 trees and more than 350 hollows within public open space city wide created by Habi-Tec – and counting! We aim to continue our work in this field and further promote ethical pruning.

For more information visit www.goldcoast.qld.gov.au and www.habi-tec.com

February 27, 2020 / by / in
Reach For The Trees With Bluelift – Ahern

Never like today Australia needs to focus on protecting and preserving its wildlife and diversity of animal species.

A pilot Tree Habitat Hollow Creation Programme started in Queensland in 2015, thanks to the joined effort of Local Government and Habi-Tec. A few years into it, not only success rates are exceeding expectations, but the whole community has come on board.

The Gold Coast Tree Habitat Hollow Creation Programme began as a pilot programme in 2015. It began by a chance site meeting between UK climbing arborist Steve Collom and I pruning a big old Euc tereticornis. Steve introduced himself and we discussed our shared interest and passion for arboreal habitat trees and urban Eucalypts. Steve carried a box of coring drills and a CCTV eel to explore tree cavities during his working day, just for the love of it. I was immediately struck by his knowledge and love for wildlife and knew I wanted to work with him.

Both Steve and I discussed habitat loss and ethical pruning, the movement beyond the Australian Standards, excessive dead wooding for hazard risk, and over-pruning generally. Following some early conceptual work, we began on an ideally located and prominent Eucalyptus grandis in Currumbin, and the programme was born.

I was able to target hardwood trees that fit the criteria in form, volume, and location. We also targeted for habitat creation those occasional Eucs allegedly poisoned by an adjacent resident. This is a notable win in terms of strategy and for lack of any real recourse against offenders in legal terms or within policy. A nice tree blocking your view might not seem so bad when instead you end up staring at a hatstand full of critters and noisy birds.

Each inherently unique tree offered opportunities to create an array of artificial hollows with the most favourable features, configuration, dimensions and protection against predators, to be ideally habitable for their intended recipients. We were spoiled for choice in many ways with tree after tree lending itself to the cause.

Through a slow-burn operation Steve and the Habi-Tec crew (partners Ash Sandercombe and brother Dan Collom), developed a wealth of expertise in creating artificial arboreal habitat hollows, while

I captured hearts and minds within the organisation and private industry, working to ensure the programme was understood and supported by the those within the broader fields of arboriculture, ecology, natural areas, urban design, town planning, and even developers.

In hindsight the programme took on a momentum and life of its own. It wasn’t until we completed about a dozen trees that we began to realise the scope for the practice to be extended further beyond the established urban areas of the Gold Coast and into the natural areas and surrounding new estates in the ‘northern growth corridor’ towards Brisbane.

The City of Gold Coast spans 1,300km² and our urban tree population exceeds 800,000 in public open space, with no shortage of potential candidates we could retain and activate. In context of the wider region the programme seemed like only a small gesture to our native wildlife as an offset, but like a ripple in a pond, the impacts spread far and wide.

At the programme’s two year mark we began auditing the early trees we created via aerial inspection, with Habi-Tec capturing data with CCTV, fixed motion-activated wildlife cameras, and visual inspection of the artificial hollows for evidence of activity to determine which species of birds or wildlife had taken up residence.

Not surprisingly the iconic Rainbow Lorikeets were most prolific, having made homes within most trees in several hollows, but we also documented uptake widely by squirrel gliders, galahs, cockatoos, corellas, possums, wood ducks, and in some of the pipes we installed the micro-bats were moving in too. The Habi-Tec team have also taken initiatives in transplanting native beehives delicately into new pipes and cavities.

The more trees we audited the more our expectations of success rates were exceeded and this only spurred us on.

Only isolated trees outside of connective corridors showed low rates of uptake but still had some activity. In the more wooded areas like Robina a big old Euc pilularis we created had corellas literally moving in as the crew packed up their equipment on the day. These critters are desperate for housing and we were building wildlife high rises to rival the famous Q1 in Surfers Paradise!

Steve, Ash and Dan were developing a deeper understanding of success and failure rates in whole trees and individual hollows. I learned that the community and City tree officers were more than receptive to the cause and we gained more and more participation from residents in monitoring and reporting on wildlife movements.

“This was a success in human terms, educating those who’ll inherit the earth in the science of biodiversity, and awareness of their natural surrounds.”

Adjacent residents received a Habi-Tec brochure in their letterboxes and would phone Steve’s better half Louella and gleefully report their kids enthusiasm for this newly built wildlife hotel in the park next door. This was a success in human terms, educating those who’ll inherit the earth in the science of biodiversity, and awareness of their natural surrounds.

Each tree is fixed with a plaque that designates the tree as habitat and warning against access, alteration or disturbance. There are 71 trees and more than 350 hollows within public open space city wide created by Habi-Tec – and counting! We aim to continue our work in this field and further promote ethical pruning.

For more information visit www.goldcoast.qld.gov.au and www.habi-tec.com

February 18, 2020 / by / in ,
Climate Change It’s An Emergency

The message from Earth is clear.

We can no longer ignore the effects of climate change. Increased frequency and severity of extreme weather conditions across the globe clearly indicate that weather patterns are changing.

Climate change occurs when abnormal variations to the climate have effects on other parts of the earth. Heatwaves, droughts, floods and current devastating bushfires have us all concerned, and more and more pressure is being placed on governments to take action to save our planet. School students right through to businesses, insurance sectors and researchers, are all calling for emissions reductions.

Co2 is a greenhouse gas that plays a significant role in influencing Earth’s surface temperature through the greenhouse effect.

But increases, caused by deforestation and the burning of fossil fuels, have upset the balance to dangerous levels and scientists across the globe are grappling with ways to take Co2 out of the atmosphere. Professor Matthew England from the University of New South Wales said the message is coming together and the problem is being taken seriously.

“Treating it as an emergency – a global health scare or a flu epidemic – has big benefits because it mobilizes action,” he said. “The reason why we’re calling it an emergency is because it does need urgent action – like responding to a terrorist threat or a global health threat.”

The Professor said we can learn from the past what we need to implement for the future.

“The 1987 Montreal protocol is well known for getting rid of CFCs and has been hugely beneficial for the ozone hole but also for ongoing climate change. Omissions of CFCs were going through the roof back then, and saving our ozone hole was seen as a genuine environmental emergency.

“Studies show that without that protocol in place, we would already be pushing up to the Paris threshold of 1.5°C temperature increase and looking at two big problems.

The next three quarters of our challenge is the carbon emissions that are now themselves out of control and posing a big risk to future climate change,” he said.

Planting billions of trees across the world is one of the biggest and cheapest ways to tackle the climate crisis according to latest research from Swiss scientists at ETH Zurich University. Professor Bastin and colleagues say time is of the essence as climate change progressively diminishes the available areas for tree restoration. Based on their model, over 220 million hectares of potential forests could be lost by 2050 if climate change continues at the current rate.

There are arguments that such a scheme would not be supported by politicians who would see countries lose economic potential as land gets covered by trees. It would also take many decades before new forests would be mature enough to store large amounts of carbon.

Others warn against monoculture plantation of forests saying respect for local and indigenous people are crucial to ensuring reforestation succeeds in cutting carbon and boosting wildlife. The implications of putting trees where they don’t belong could be serious; misplaced flora could kill local ecosystems, weaken biodiversity, dry up water supplies and make areas more prone to fires. [Carrington, 2019]

Meanwhile Australian scientists are testing our amazing diversity of tree flora to find plants that will have the capacity to adapt to our changing climate.

Professor David Ellsworth from Western Sydney University is one of the chief investigators for the project, aptly named ‘Which Plant Where’. He said plants that might make good candidates are more from inland areas or bioclimatic regions where there has been historical drought and heatwaves of intensities expected for the future.

“We expect drought tolerators such as Emu Bush, Wilga, Brachychiton, to be the sort that we can plant more in urban areas in the future. However, heat and drought tolerance of tree species in an Australian context are not sufficiently understood. Hence, our project incorporates a comprehensive research program to help us minimise losses and ensure future street tree and urban plantings will successfully grow in place for the coming decades.

“We want to create confidence among the general public, gardening and nursery communities to be able to see their plants survive through the long term,” he said.

The university has large advanced climate control glasshouses where they can manipulate moisture and temperature. Plants are put through simulated drought and heatwave conditions. Bioclimatic modelling work looks at the relationship where a species occurs and the climate of that region. Maps are developed to show which areas are suitable for the species both now and in future climates. Traits of particular plants will also be listed including depth of roots, shape of tree, canopy cover, flammability, biodiversity co benefits.

This information will be developed into an online tool for people when they are deciding what to plant in a particular setting. See more on this project and others in future issues.

References Carrington, D. (2019). Tree planting ‘has mind-blowing potential’ to tackle climate crisis. The Guardian. [Online] Available at: www.theguardian.com/environment/2019/ jul/04/planting-billions-trees-best-tackle-climate-crisis-scientists-canopy-emissions [Accessed 12 Dec. 2019].

February 12, 2020 / by / in ,