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This poor tree has been vandalised at least three times since the tree was planted in 2015.   Council did put up a small sign saying that it had been vandalised, but this was not a deterrent.

This poor tree has been vandalised at least three times since the tree was planted in 2015. Council did put up a small sign saying that it had been vandalised, but this was not a deterrent.

The Inner West Council planted a street tree in a pocket of grass in Myrtle Street Marrickville.  A tree was much needed at this location because it is bare & dare I say ugly.

I was very happy they planted at this location.  Then the tree had several branches snapped off.   The tree grew more branches & the tree was vandalised again.  I started to doubt that this was a random act.

The tree’s desire to live was strong, so it grew some more & started to look strong & lush.

I went by the tree today & its leaves are dry & crisp.  Its thin branches are still alive showing that whatever was done to this poor tree happened recently.

Unfortunately, this tree is dying.  To me it appears that some sort of chemical was fed to it to make sure this determined tree would not rise up again.

It is beyond my comprehension why people rob the community & the wildlife of street trees.   One tree may not matter much, but we have an urban forest classified as ‘poor’ in terms of percentage of canopy cover.  We need trees just to break even in terms of the norm in Sydney.  We also need trees for good public health & we desperately need trees in terms of climate change.

We need more trees in Marrickville & throughout the old Marrickville municipality.  We need bigger, more shade-producing trees.

2016 was the third year in a row of record-breaking heat.  “The average global temperature last year [2016] reached about 1.1°C above the pre-industrial era, which has brought us extremely close to the 1.5°C target established at the historical December 2015 Paris climate summit.”

1.1°C may not seem much, but you only have to have been in Sydney this past month to experience what a heatwave feels like.  Heatwaves & extreme weather events are all part of this global rise in temperature.  The Arctic is the warmest on record, sea ice is melting at alarming speed, coral reefs are bleaching, the oceans are heating up….  There is more, but you get the picture.

Now here is where is gets really interesting.   “Australia is especially at risk as we are 8°C hotter than the world average”

We cannot keep relying on air-conditioning.  One day there will be too many of us using too much power for the system to cope with & we won’t be able to turn on the air-con.  Then people will die.  Perhaps thousands of people.  Death in numbers like this has happened many times before.

We won’t be able to easily acclimatise to the heat either.   The following is part of a summary of research titled, ‘Limitations to Thermoregulation and Acclimatization Challenge Human Adaptation to Global Warming’ published in 2015.   They knew then that it will be difficult for the human race to adapt.   Thousands of us are likely to die in each heatwave event.  That will be a devastating experience for many.

Human thermoregulation and acclimatization are core components of the human coping mechanism for withstanding variations in environmental heat exposure. Amidst growing recognition that curtailing global warming to less than two degrees is becoming increasing improbable, human survival will require increasing reliance on these mechanisms. The projected several fold increase in extreme heat events suggests we need to recalibrate health protection policies and ratchet up adaptation efforts.”   You can read the whole paper here for free –

I hope the Inner West Council plant another tree at this location.   Tree vandals cannot be the deciders on how the rest of the community live, their health, the level of pollution they live with, their ability to have a beautiful suburb, how cool their streets are or whether the wildlife can have habitat & food.  The culture must change.  The streets belong to all.

As I post this I am listening to the weather forecast on the TV news.  They are forecasting a heatwave two days from now on Tuesday.   That will be the third heatwave for Sydney in 2017 & it is only January.

New Canterbury Road Dulwich Hill - wide footpaths & no overhead power lines.

New Canterbury Road Dulwich Hill – wide footpaths & no overhead power lines.

New Canterbury Road on the side of the powerlines.  Hot!

New Canterbury Road on the side of the powerlines. Hot!

Today is International Day of Forests. 

Forests occupy one third of the Earth’s land area.  13-million-hectares of forest are destroyed annually accounting for 12-20% of the global greenhouse gas emissions that contribute to global warming.  Half of the world’s forests have been lost in less than 100-years, which is quite shocking in my opinion.

The Department of Agriculture, Fisheries & Forestry says, “Australia has 149 million hectares of forest. Of this, 147 million hectares is native forest, dominated by eucalypt (79%) and acacia (7%) forest types, and 1.82 million hectares is plantations. With an estimated 4% of the world’s forests, Australia has the world’s sixth-largest forest estate and the fourth-largest area of forest in nature conservation reserves.

“As much land has been cleared in the last 50 years in Australia as was cleared in the previous 150 years. For the year of 1990, land clearing in Australia totaled more than half of that which was cleared in Brazilian Amazonia. Land cleared in Australia in 1994 was equal to that which was cleared in the previous five years. (This included 640,000 hectares of virgin bushland.)”

Here are some of the points covered in United Nations Secretary-General Ban Ki-Moon’s statement for 2014.

  • “Forests are the lungs of our planet.  They cover one third of all land area and are home to 80 per cent of terrestrial biodiversity. 
  • It is estimated that 1.6 billion people depend on forests for food, fuel, shelter and income. 
  • The World Health Organization estimates that between 65 and 80 per cent of people rely on medicines derived from forests as their primary form of health care. [Again, a quite shocking statistic].
  • Forested catchments supply three quarters of freshwater, which is essential for agriculture, industry, energy supply and domestic use.
  • The International Day of Forests is dedicated to raising awareness about the importance of all types of forests and trees to our economic, social, environmental and cultural well-being.  However, awareness must be coupled with concrete action.”  For the full speech see –

‘The Conversation’ has just published an interesting article on the Federal Government’s plan to delist around 74,000 hectares from Tasmania’s World Heritage.  It seems appropriate to include in this post. –

An earlier article from this month says, “a key advisor to the World Heritage Committee has flagged concerns with the Federal Government’s plan to delist 74,000 hectares of Tasmania’s World Heritage Area.”  This is worth reading too. –

I can find no mention of the urban forest or of any planting events across Australia, though there must be at least some schools participating somewhere.  To me this is a missed opportunity to educate & enthuse the community regarding the importance, as well as the benefits of urban trees.  Even one tree planted with celebration would be better than ignoring the day completely.

Last week someone on Twitter shared with me that 8-10 newly planted street trees had been planted on one day in Newtown – then poisoned overnight.

While this kind of behaviour is not the norm, tree vandalism happens frequently enough to be of concern.  Not only does it waste significant amounts of rate-payers money, it also often prevents replacement trees being planted as quite understandably, Councils do not want to waste more money planting replacement trees when there is a high chance they will be poisoned again.  They also have a budget for street tree planting & when the money runs out, no more trees can be planted until the following year.  The vandal wins & the community loses.

I speak to many people when they see me photographing street trees.  An alarming number have negative opinions of the tree outside their home or the trees in their street.  The most common complaint is leaf litter or litter from dropping seeds.  When I try to discuss the benefits this tree brings them, including the increased value to their property, I usually get greeted with sneers & a dismissal of the tree.  Most would happily lose the tree if they could.

To me this is a kind of emergency in Marrickville municipality.  It means that trees get poisoned or undermined in a range of ways & this is likely to prevent Council successfully increasing the urban forest.  If our urban forest does not increase significantly, I believe we will be in real trouble in the years ahead.

Australia is breaking weather records like crazy over recent years & the temperature is increasing.  Without a decent urban forest we are going to have problems with heat, heat stress & the health impacts from heat stress.

In 2009, 374 Victorians died as a result of a heatwave.

The death rate from heatwaves is higher than our worst bushfires & every year they cause more deaths in Australia than any other type of natural disaster.  Extreme heat events are responsible for more deaths annually than hurricanes, lightning, tornadoes, floods, and earthquakes combined.   An astounding 52,000 people died as a result of the 2003 European heatwave.

A Climate Council report called ‘Australian Heatwaves: Hotter, Longer, Earlier and More Often,’ released in February 2014 found the following –

  1.    “Hot days, hot nights and heatwaves are one of the most direct consequences of climate change.
  2.   Heatwaves have increased across Australia.
  3.    Climate change is making many extreme events worse in terms of their impacts on people, property, communities and the environment. This highlights the need to take rapid, effective action on climate change.
  4.  Record hot days and heatwaves are expected to increase in the future.”

All those hard surfaces will retain the day’s heat & radiate it back out at night keeping the nighttime temperature high.  This impacts on how we sleep & for some, if they can sleep.  Air-conditioning will need to be used more just to be comfortable, resulting in more carbon output.  There are many in our community who cannot afford to have air-conditioning installed.

Trees keep the streets & our homes cool for free if they have a decent sized canopy & are planted in the right places around our homes.  All we need to do is plant them, water them & nurture them.  The rewards for us are manifold & I am not even considering the wildlife, who I believe have an equal stake in the environment as we do.

If Councils do not start to seriously educate the community on the value of trees we may find ourselves in a situation trying to increase the urban forest in times when it is much harder & more costly to keep a tree alive.

World days like the International Day of Forests are a perfect opportunity to educate in a way that is non-threatening & can include an element of community building, pride building & fun.  The question in my mind is why is this not happening?  Even the UN has relegated the day to an awareness-raising event.  It will fly by on social media supported by ‘shares’ by people who like trees, but how many trees will be planted as part of this event?

While I love that a resident  planted this space, someone vandalised the tree.  This is not uncommon to see around Marrickville municipality.

While I love that a resident planted this space, someone vandalised the tree. This is not uncommon to see around Marrickville municipality.

You can tell by the aged stakes & canvas ties that this tree is at least a year old.  It takes years for a tree to reach a decent size & start providing real benefits to the environment.

You can tell by the aged stakes & canvas ties that this tree is at least a year old. It takes years for a tree to reach a decent size & start providing real benefits to the environment.

This is a very common sight across Marrickville LGA.  I think trees are amazing to survive these conditions.

This is a very common sight across Marrickville LGA. I think trees are amazing to survive these conditions.



North Newtown streetscape providing lots of shade

North Newtown streetscape providing lots of shade.  This is a normal streetscape for this area.

Compare with a street in Dulwich Hill that actually has many street trees

Compare with a street in Dulwich Hill that actually has many street trees

There is an interesting article in The Conversation written by Prof. Rod Keenan & Benjamin Preston, both from the University of Melbourne.

Some points in the article –

  • Victoria currently has an average of 9 days per year of temperatures above 35C.  No action on greenhouse emissions will likely result in an average of 21 days a year with temperatures above 35C by 2070.
  • “Combine that with increasing urban density, more hard surfaces & less greenery, & a larger, older & more multicultural population, & the potential impacts from heatwaves start to multiply rapidly.”   Think of the development already in Marrickville municipality & the huge amount of development to come.

The Authors suggest two ways to help mitigate this & I think these are applicable Australia-wide –

  1. Increasing the ‘green infrastructure’ by 10%.  Green infrastructure means street trees, parks, green roofs, green walls & retaining water.

I’d suggest 10% is the absolute minimum, but can you imagine the positive change if the Marrickville urban forest was increased by 10%.

The City of Melbourne is planning on increasing their urban forest canopy cover from 22% to 40%. The City of Sydney is aiming to increase their urban forest by 50% by 2030 (just 16-years away) to help lower the urban heat island effect.

  • 2. Education.

“Health awareness programs can promote related benefits such as improved air quality; planners can reduce the red tape involved in planting street trees; local governments can identify priority neighbourhoods for development, protect existing greenery, & implement water-sensitive urban design.” 

“Increasing green infrastructure will also require the use of private space – one major challenge will be to give private landowners the incentive to keep or install greenery & incorporate vegetation into building design.”

Although Sydney has not experienced a true heatwave this summer, it has been very hot.  Melbourne & Adelaide both experienced two heatwaves this January, baking over a number days.  On 16th January, Adelaide was given the title of ‘the hottest city in the world’ with a temperature of 44.2C, still short of the forecasted 46C.

An article on Care2 discusses the American city of Phoenix trying to cope with 100-degree nights.  “The city averages more than 100 days a year with temperatures reaching over 100 degrees. (37.7C)   In 2013, 115 days hit 100 degrees. In 2011, the city set a new record for days over 110 degrees (42.3C) with 33. That’s over one month of the year with scorching highs. This winter has so far been warmer than average.”

Temperatures are rising everywhere.  The urban heat island effect is increasing those temperatures, & importantly, not allowing the temperature to drop after the sun goes down.  Phoenix has “a shade plan for the built environment & also a plan to “frankly just plant more trees.”  See –

We need to start planting now in both private & public spaces if we are to ever hope to be able to cope with projected temperatures.  Sydney’s temperature is expected to be like living in Rockhampton in Subtropical Queensland.  See –

Marrickville Council needs to decide how much to increase the urban forest & set & meet targets to achieve this.  The yearly budget allocation needs to be such to allow this to be achievable.   I have often wondered whether public trees & parks are lower down in the budget & whether these are seen as not as important as grey infrastructure.

Certainly we need to do what we can to keep the trees we have & this means treating them for diseases, fertilizing, mulching & pruning where necessary.

In my opinion, the community needs to help Council keep new trees alive by continuing to water trees once a week when Council has stopped water 12-weeks after planting.  It only takes a few hot days to lose a tree & if we look realistically, the bulk of our street trees are living in very harsh conditions.  Many are either hemmed in by concrete or in visibly dry & compacted soil.

I know there are many who will baulk at the idea of watering a public tree, but it is commonplace in many countries overseas.   The US for example, has a strong community involvement in public trees, whether planting them or looking after them.  Both the US & the UK have community ‘Tree Wardens’ looking after public trees.  These people are not tree experts.  They receive training by their Local Council to do the work they do.

Keeping that tree alive will help reduce your power bills as they help cool the air around your house.  Street trees clean up the air by removing particulate matter from vehicles, so better quality air comes into your home.  They also increase the value of your residence or business amongst many other benefits, so it stands to reason that taking care of the tree outside your property brings significant returns.  Better a living healthy tree, than a dead tree or a sapling that struggles to grow & may take many years to reach a decent size.

Older larger trees are far better at carbon sequestration than smaller trees – another reason why it makes sense to look after them.

You can read the full article here –

Tall shady street trees are the norm in Chippendale

Tall shady street trees are the norm in Chippendale

Canterbury Road - this section is mega-hot on a sunny day.

Canterbury Road – this section is mega-hot on a sunny day.

While there are street trees, this is still a hot street in Marrickville

While there are street trees, this is still a hot street in Marrickville

Young street trees & landscaping outside the old seagrass factory in Stanmore that has recently been developed into housing.

The Conversation – “an independent source of information, analysis & commentary from the university & research sector” has published yet another fabulous article, this time about trees.  The article was written by Gregory Moore – Doctor of Botany, University of Melbourne & published 30th January 2012.

Greg Moore Senior Research Associate of Burnley College, University of Melbourne was Principal of Burnley from 1988 to 2007, & Head of the School of Resource Management at the University from 2002 to 2007.  With a general interest in horticultural plant science, revegetation & ecology, Greg is particularly interested in arboriculture. He was inaugural president of the International Society of Arboriculture, Australian Chapter, & has been a member of the National Trust’s Register of Significant Trees since 1988 & chair since 1996. He has served the Board of Greening Australia (Victoria) since 1988 & chaired Treenet since 2005. He is on the board of Sustainable Gardening Australia & is a trustee of the Trust for Nature. He has written two books, contributed to three others & has published over 120 scientific papers & articles.”

‘The Conversation’ allows this article to be republished so here it is in full.  The use of bold is my emphasis.

For a great return on investment, try trees

Perhaps it is a pity that so many Australians think of our parks, gardens, streetscapes & urban landscapes only in terms of their aesthetics. While green spaces are beautiful & decorative, these attributes can mask the many functions vegetation serves in cities, to the point where its economic, social & environmental benefits are overlooked. Yes, trees are beautiful; but more than that, they save our cities a lot of money.

Cities are biodiversity hot spots because of the variety of habitats available in public & private open space, including front & back yards. Urban landscapes & trees have been wonderful but silent assets in our cities for decades & even centuries.

One of the many mature Fig trees in Johnson Park Dulwich Hill. They & other mature trees in this park are a real asset to this community.

They are major urban infrastructure assets. I often hear it said that; “There are better things to use water on than plants and gardens”, but I challenge you to name them. What else delivers so many benefits immediately: benefits that last centuries into the future, which prolong healthy lives & make cities both sustainable & livable?

At a time of climate change, it is worrying that both private and public open spaces are threatened by urban renewal & development that puts at risk long-term sustainability. In many of these developments there is insufficient open space – public or private – to plant large trees, & the opportunities for vegetation to ameliorate the heat island effect, lower wind speed, provide shade & reduce energy use are lost. This affects the economic viability of such developments, as well as its long term environmental sustainability.

The shade provided by trees drops temperatures by up to 8°C: there is real economic value in that. Shade can reduce air conditioner use by 12-15%, which also decreases carbon emissions from our largely brown-coal-generated electricity.

When 11 million trees were planted in the Los Angeles basin, it saved US$50 million per annum on air conditioning bills. Large trees were removed from school grounds in the name of safety after the Black Saturday fires, without thought of the shade they provided. Consequently, large shade sails had to be provided to protect students from excessive summer sun.

It is more difficult to place a value on reduced wind speeds (up to 10%) due to the presence of vegetation, or on protection that trees provide from hail. However, we do know that under climate change winds will be stronger & that severe storms will be more prevalent. Indeed, Victoria has already suffered the effects of several major wind & hail storm events over the past few years.

Urban vegetation also removes atmospheric pollutants. It was calculated that the vegetation of New York provided US$10 million of benefit in pollution removal in 1994. resources/downloads/Tree_Air_Qual.pdf  Sadly there are few similar studies for Australian cities. However in the only study of its kind, economists found that each Adelaide street tree provides a minimum annual benefit of $200 per year & that it was an under-estimate of the real value.

Vegetation also holds & absorbs water during more intense rainfall events – unlike concrete & paved surfaces. The economic value of reducing localised flooding could be substantial.

Vegetated landscapes, especially those containing trees, improve human heath, extend life spans, reduce violence & vandalism, and lower blood pressure.

Vegetation humidifies the air, easing breathing & reducing the need for medication in those with respiratory difficulties. In reducing the urban heat island effect, trees can also substantially reduce the excess deaths that occur, predominantly among the elderly, during heat waves. It is often forgotten that the fires of Black Saturday killed 172 people, but the heat wave surrounding it was responsible for 374 deaths.

Petersham is lucky to have such a lovely streetscape.

There is ample evidence that treed landscapes foster both active & passive recreation. Green & leafy environments will be one of the vital strategic tools in dealing with children lacking exercise & becoming obese, encouraging an ageing population to exercise & curbing ever-increasing health costs. The human health benefits can save society a truck-load on medical & social infrastructure costs.

Melbourne is one of Victoria’s biodiversity hot spots. The parks, gardens, streets & front and backyards provide a very diverse range of plant species that generate a myriad of habitats & niches for wildlife. High density urban developments & inner city renewal make it virtually impossible to grow trees in places that were once green & leafy. We rarely ever see the real costs of such developments.

In the past decade tree populations in many Australian cities have declined, particularly with the loss of private open space. While the costs, damage & nuisance values attributed to trees are widely known, the benefits they provide are often subtle & under-appreciated.

Urban vegetation provides economic & ecological services to society. They are assets which warrant the expenditure of resources such as labour, energy & water. Such expenditure is not wasted: trees & urban landscapes provide far more economically & ecologically than they use. In any comprehensive & fair calculation urban trees & landscapes are worth more than they cost.

* data-tracker

This article was originally published at  Read the original article –

Landscaping with young trees has been used to block off a road connecting with Ewart Street Dulwich Hill. It always looks good. Unfortunately one tree has been lost.

1.  Professor Nigel Tapper of Monash University, a speaker addressing the National Tree Symposium at Adelaide University of Adelaide said urban trees actually save lives during heatwaves. Treenet Director David Lawry spoke about stormwater being diverted from the gutter to street trees. A test is being done in Unley Adelaide to measure its affectiveness. …the devices could deliver up to 400 litres of water directly to trees during moderate rain, resulting in healthier trees, more comfortable urban environments & less stormwater getting to waterways & the sea. To me it makes absolute sense to channel rainwater from the gutter into the area around the street tree. To achieve this is quite simple & only requires a remodeling of the kerb.

The National Tree Symposium also discovered that proposed changes by the South Australian government to significant tree regulations will leave a large amount of existing trees unprotected by the equivalent of a Significant Tree Register.

2.  Darwin has a tree emergency on its hands with between 60-70 large Weeping Rosewood trees showing symptoms of fusarium wilt (a fungal disease not indigenous to Australia), which spreads by spores in the soil.  If this is the case, Darwin could lose thousands of trees within the coming decade.

3.  The ACT’s Council, the Department of Territory & Municipal Services has been ordered to improve upon their policy & procedures of public tree removal by becoming more transparent & accountable to the community. 20 – 40% of the ACTs 630,000 park & street trees are expected to be axed within the next 20 years.  I’d be very busy if I lived there.

Heading down to the Cooks River



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