Media release from Independent arborist 31.10.2011


White cedar trees in William Street Mayfield


Background: Mr Craig Hallam is an arborist who works for over 100 Councils both nationally and internationally. He has inspected the Laman Street trees on several occasions. His company ENSPEC does dynamic testing of mature trees.He spoke with Newcastle City Councillors recently about how to manage the trees and this is his statement after seeing the 7:30 NSW/Stateline report from 28th October.

‘Newcastle City Council’s arborist and spokesman Phil Hewitt claimed in the media last week [7:30Report NSW, 28th October 2010] that the tree species that forms the iconic avenue in Laman Street, the Hill’s weeping fig, is prone to failure in wind. This is incorrect – this species is found in high wind areas in Australia, the sub tropics and tropics.  So the species is ideally suited to high wind areas.  From what Mr Hewitt says, Newcastle must have special high wind speeds that places like Brisbane and Cairns don’t have.

2.      Mr  Hewitt claims many failures have occurred with this species, but what council has failed to disclose is whether there was any human intervention in the root plate area of the trees that did fail.

 I don’t believe council ever followed science to ascertain why the so called previous failures occurred.  It’s most likely that the failures relate to some form of human intervention where council cut the tree roots when they were replacing kerbing or carrying out civil works to repair the road. 

‘Have they tested the Laman Street trees to ensure there’s no fungus affecting them? If council had found some species of fungus affecting the trees’ root plates that may explain why this species fails more in Newcastle (only Newcastle) than any other area of Australia, which is what they allege.  If this was the case, council could have started to manage the process using natural antagonists to prevent the fungus from destroying the root plates.

3.       Mr Hewitt only thinks the trees will fail; Council has no scientific evidence to support this, it is just an opinion.

4.       Re the reports commissioned by council: these  have peer reviewed the original council arborist’s initial report as stated on ABC Stateline. Each time the initial report was peer reviewed by council’s selected independent arborists, they have added their observations and findings, but it still refers back to the single original council report.

‘There has not been a neutral arborist assess the trees [- that is, one commissioned neither by Council nor by Save Our Figs].  In January when I visited the site, Mr Hewitt explained for over half an hour how the trees were moving in the ground due to poor root plate structure and said that I would find the same.  I never saw any evidence to support Mr Hewitt’s claims on site.

5.       Mr Hewitt states the trees will fail around 80kph. If this is the case, how come the same species does not have total failures in other regions of Australia at this wind speed, or in adjoining towns to Newcastle?  This species normally withstands wind speeds within the wind design speed that is used for actual building specifications.  If Mr Hewitt is correct, then many buildings should be failing as well.

6.       Mr Hewitt states that he cannot play Russian Roulette with trees on streets; if this is the case, Newcastle City Council is now more exposed than ever, as many other species fail at a greater rate than Ficus species, so council will need to remove all street and road reserve trees.  Is this an acceptable environmental approach to managing an Urban environment? If it is as Mr Hewitt claims, Australia is going to have a major heat island issue in the urban landscape to manage in the future.

7.       Mr Hewitt stated that the figs have limited rooting space in the street environment. All the other species of trees and in most cases other species in a street environment have less rooting area than the fig trees in Laman Street so they will need to be removed as well or council is at risk for every tree in the future.

8.       If any tree now fails in Newcastle’s council area, affected people will be able to sue council as council have made some very definitive statements on trees’ root plate structure without thoroughly investigating the cause of the perceived root plate failures of previous fig trees.

9.   If council has so many trees posing a risk throughout their area of management, how do they gain insurance coverage and further to this, how could the council’s arborists ever have let the City of Newcastle move into such an extreme risk that could cause injury or death to residents and anyone visiting the city.
‘I still stand by my observations that the trees are not at risk of an overturning moment from root plate failure at present under design wind loads as described in the AS/NZS 1170.2:2011 : Structural design actions – Wind actions.

‘Council should adopt further investigation using dynamic loading methodology and also conduct sampling for fungus at this site to provide a clear transparent analysis that is made using science and measurement instruments; in this way human opinion is taken out of the equation’.


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2 Responses to “Media release from Independent arborist 31.10.2011”

  1. Shani Sandner Says:

    Read this to all the non-out there…

    “Oh yeah of little faith”

  2. jacinta dalton Says:

    Could this be given to Media Watch following up the report on the 7.30 report?

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