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A new report called ‘Neighborhood greenspace and health in a large urban center’ has found that “people who live in neighborhoods with a higher density of trees on their streets report significantly higher health perception and significantly less cardio-metabolic conditions … [cardio-metabolic conditions include diabetes, heart disease or stroke.]
We find that having 10 more trees in a city block, on average, improves health perception in ways comparable to an increase in annual personal income of $10,000 and moving to a neighborhood with $10,000 higher median income or being 7 years younger.
We also find that having 11 more trees in a city block, on average, decreases cardio-metabolic conditions in ways comparable to an increase in annual personal income of $20,000 and moving to a neighborhood with $20,000 higher median income or being 1.4 years younger.” See – http://bit.ly/1G9OL9u
It’s easy to see why. Trees & the view of trees make people feel better. The presence of good-looking trees (not the small spindly things passing for street trees in our municipality or the poor butchered trees) improves peoples’ mental, physical & spiritual health. Apart from “significantly less” diabetes, heart disease & stroke, depression rates lessen & overall happiness increases. A good urban forest is vital for a community’s health & should be a priority for every local council.
Marrickville municipality’s urban forest is 16.3%, which is dismal & one of the lowest in Sydney.
Recently Marrickville Council said on Facebook that they are planting “over 400 trees” this season. This is great, but they also planned for the removal of 1,590 street trees since December 2012, plus the other trees removed that were not identified for removal in the Tree Inventory. The bulk of the trees to be removed were mature. It takes a long time to replace the benefits provided by a mature tree.
At 400 new trees per year, it would take 4-years just to replace the 1,590 street trees removed (or still to be removed) & this does not equate to increasing our urban forest. It is just breaking even with what is currently considered a poor level of canopy cover.
As for the research finding that “having 10 more trees in a city block, on average, improves health perception in ways comparable to an increase in annual personal income of $10,000 and moving to a neighborhood with $10,000 higher median income or being 7 years younger,” this too is understandable.
One only needs to travel to nearby suburbs like Alexandria, North Newtown, Darlington, Redfern, Waterloo, Darlinghurst or Paddington to see the enormous & positive difference good street trees can make to an area. Travel over the Sydney Harbour Bridge to the North Shore & the differences are more pronounced, but so are the housing prices. People pay much more to live in leafy areas.
Trees make an area. They increase livability. They provide beauty, muffle the sound of traffic, remove pollution, provide shade & shelter & bring in the wildlife.
Even the sound of birds makes life nicer. This is something that is taken for granted when one is used to living with the sound of birdsong, but when there are few trees & fewer birds, one notices the lack of birdsong. Unfortunately many have become accustomed to the lack of birdsong & don’t notice the “wildlife poverty.”
Earlier this week I traveled to Baulkham Hills via Pymble. After looking at their urban forest, I am convinced that we have “tree poverty” here in many parts of Marrickville LGA. There is no reason for this other than Council’s decision on what species of tree they plant & where they plant. To me it is sad. We have many wide roads & many places where trees could be planted, yet the Tree Inventory said there was only 1,544 “vacant planting opportunities.”
The Tree Inventory found that Marrickville municipality had a total of 22,608 street trees in December 2012. That may sound a lot, but remember we have one of the smallest tree canopies in Sydney. Although Council says they are committed to increasing the urban forest, they have not given a percentage target of their planned increase. This is unlike other local councils throughout Sydney & Australia who numerically disclose their intended target. This means any amount of trees planted will allow Council to say they have achieved their Key Performance Indicator for that year & the community will be none the wiser.
If the ‘vacant planting opportunities’ do get filled, this will mean our urban forest will have a total of only 24,152 trees. This is not nearly enough in my opinion. The idea that our urban forest will only ever be as good as an extra 1,544 trees makes me feel frustrated. It means that the urban forest will likely continue to be as it is currently & our municipality will not get the injection of streetscape beauty needed in many of our streets.
To reiterate some of the most important findings of the Tree Inventory –
- 2,034 or 9% of our urban are in poor health or dead.
- 4,068 trees or 18% of our urban forest have poor or very poor structure or have failed. This makes 6,102 trees in total that are sick, have poor structure or are dying or dead.
- 4,236 trees were identified as causing footpath damage, kerb damage, road damage or damage to private infrastructure.
- 15,226 trees or 69% are mature.
- 4,540 trees or 20% are assessed as having a Useful Life Expectancy of 10 years or less.
- Compared to 8 other Councils Marrickville street trees are smaller in size, so this will be even more noticeable when the identified 20% or 4,540 trees come to the end of their safe useful life expectancy by December 2017 & are removed.
- 7,997 trees were identified for minor maintenance through to tree removal. 7,011 trees were recommended for major & minor tree maintenance works. This is a total of 15,008 trees of which 88% are Moderate Priority (within 2 years) or Low Priority (within 4 Years).
As the research shows again & again – trees are good for our health & the more trees there are, the better our health on all levels.
I discovered some Mistletoe growing in a Gum tree in Marrickville. Not knowing much about this plant I did some research & found out that Australia has more than 90 species of Mistletoe. I also came across some interesting information from ‘The World Today’ on ABC Radio.
Mistletoe in Australia is always a native plant. It has a bad reputation for killing trees, but Associate Professor David Watson from Charles Sturt University says, “pretty much all of the public’s perceptions about Mistletoe are fundamentally incorrect.” Mistletoe does not kill trees, nor is it poisonous to people or livestock saying that these are myths.
In fact, his recent research has found Mistletoe encourages biodiversity. For 5-years he & another researcher removed all Mistletoe from some farms near Holbrook, near Albury in NSW. The results were unexpected.
“Within three years of taking mistletoe away doing nothing else just removing mistletoe plants from the canopy, we lost more than a third of the woodland dependant bird species. So to do one small habitat manipulation & see such a dramatic & almost immediate effect is very strong evidence & shows that not just an indirect effect, mistletoe really does have a direct positive effect on biodiversity.”
He also said that Local Councils usually have a policy of removing Mistletoe, but that this is the wrong thing to do because Mistletoe has such a positive effect on biodiversity.
“….rather than seeing Mistletoe as a problem in & of itself, it’s far better to consider it as an indicator of broader scale ecosystem health. ….and it will come back.” See – http://bit.ly/10NUkGf
Little birds like to nest in Mistletoe. It also produces incredibly nutrient-rich leaf litter, which would be great to use in the garden.
That it would be great for small birds was the first thing I thought of when I saw the Mistletoe. All this is something to think about if you have Mistletoe growing in your tree. It’s likely that others will tell you that you have to remove it because the myths about this plant have been around for a long time, but its presence shows that there is great biodiversity happening in your spot & that the little birds have somewhere to nest. As evidence, there will likely be lots more birds around. These are plenty of reasons to keep it.
Seems the Fig trees at Tempe Reserve are not alone being affected by psyllids. Large numbers of Eucalypts in the Mt Druitt/St Marys region are losing their leaves after an outbreak, with an Arborist saying that a number of psyllid-affected trees in Colyton Public School need to be removed.
Blacktown Council & the University of Western Sydney have started a 12-month research project “to learn more about psyllids & the damage they cause.” http://bit.ly/Tt26XQ
Grey box psyllid is affecting trees in Penrith, with many trees looking like they are dying. The psyllid infestation has traveled as far as the Blue Mountains. http://bit.ly/mRPO0B & http://bit.ly/PV7CMK
Scotts Park in San Souci is a beautiful place with quite a number of environmental initiatives of which I will write about over a couple of posts. It is a park full of large trees. There is open space, but unlike most of the parks in Marrickville LGA, the trees are not around the periphery, but scattered all through the park. You get a strong sense of being away from the traffic.
About 40 metres from the road there is a massive Fig tree that would have to be 100-hundred-years-old or more. There was a gathering of people having a picnic under its boughs while we were there. Above in the massive boughs was a family of Little Corellas with a baby making a constant noise calling for more food. Birds feature a lot in this park.
It was only after walking around the park that we noticed concrete in the base of the Fig tree. When I say concrete, it was around 1.5 square metres of concrete. The middle & base of the tree had rotted. Rockdale Council must have decided to scrape out the rot & fill in the space with concrete allowing the tree to be retained. Apart from the rot, the tree itself is very healthy, has fruit & shows no dieback. In the wild, this tree would have simply developed a hollow, which I am told, often has no affect on the strength of the tree & the hole itself creates homes for wildlife.
There is still some rot & I guess Rockdale Council will come again & add some more concrete. A few years ago they planted a replacement Fig & this tree is growing quite happily beside the older Fig. If one day the mature Fig needs to be removed, the replacement tree will be much larger so the visual aspects of the park will not be negatively affected. I am impressed first with treating the tree & retaining it, but also having the foresight to plant a replacement tree well before the older tree needs to be chopped down, if that does happen. Well done Rockdale Council.
Talking about Fig trees …. A Fig had to be removed from near 16 Thornley Street in Steele Park Marrickville South last year because of rot & other problems. Marrickville Council said at the time, “It is proposed to be replaced with a Moreton Bay Fig of size 100L or greater.” I posted about this tree removal on 5th March 2010 & a replacement Fig has not been planted at the time of posting.
I made a short YouTube video of the Fig tree in Scotts Park here – http://www.youtube.com/watch?v=H22dVuh7gLo