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In praise of tree hollows and the urban forest

The impact of population growth on our cities and suburbs increases the demand for housing, jobs and transport systems. Energy consumption increases temperatures if its not of the renewable kind. Larger, more crowded cities mean less space for the trees, parks, bushland and other open spaces which constitute our ‘green infrastructure’.

This sounds like humans are in competition with the very substance of what we need to ensure that our cities are fit for purpose. The purpose boils down to being fit for human habitation, which by direct correlation include habitation for all the species that we rely on for our quality of life.  The human cityscape has to fit into the natural wilderscape that is nature – the trees, the birds, the mammals, the insects, the web of life within which the human society is embedded – not the other way around.  Rather than attempting to re-engineer nature in our own image, we think it best to re-imagine human society in the image of nature.  After all, nature has been around a lot longer and has many life-times of experience from which we could learn a thing or two.

‘Green infrastructure’ is critical to alleviate human pressures. For example trees filter air pollution, shield homes and buildings from the sun, decrease energy consumption, provide habitat for urban wildlife, shade us as we walk and play and generally make our suburbs and streets more appealing places to work and raise families.

It’s time that the community and governments at all levels begin to value the benefits as well as the costs of urban trees. Green infrastructure needs to be considered in the same way as other forms of infrastructure and integrated into our planning at every level. (1)

In recognition of the growing interest in the values of urban greenery, Rethinking the Urban Forest inaugural conference was held on Friday, 24 May 2019 at the Addison Road Community Centre, Marrickville (Sydney).

Jennifer Newman, Wiradjuri woman, set the scene: We are all part of country; We are each on a journey as those who have gone before have done and our mission is to keep country on behalf of those who follow; Part of this mission is ‘nourishing the terrain’ that gives and receives life – the life that we live in; Great trees do not grow to fullness overnight – we are therefore entrusted with the responsbility to see that they have the opportunity to reach their full potential, thus becoming part of the ‘nourishing the terrain’ cycle within which also can reach their full potential.  The tree – the forest – is an excellent example of reciprocity in action.

Jess Miller, 202020 Vision, noted: Compared to the tree cover of 100 years ago, where are all the trees?; What is the metropolitan plan for urban trees and forests?; We can’t continue with population growth at the expense of tree cover; What’s the story in relation to urban greenspace?  What are the narratives: aesthetics – relaxation – health and wellbeing – wildlife – community participation – maintenance and costs – safety?

Michael Sullings, Environmental Arboriculture, noted:  There is a need to see trees as houses for animals – since people seem to love animals, by extention people might pass on this love to preserve trees.  And, there is also a need to reframe our story to consider that we also live ‘in’ trees – that is, amongst and within treescaped areas.  Trees are ‘keystone structures’ – they are more than an individual organism.  With hollow formation, after 60-80 years, trees provide homes for animalsArtificial tree hollows provide life after death    While humans see hollows as structural defects, these hollows are housing infrastructure for wildlife.  We now have a tree hollow deficit in NSW.  When we cut down all or most old and so called dead trees, we are destroying the housing estates for native animals.

Abbey Mellick Lopes, Western Sydney University, is involved in research focussed on the relationship between design and social arrangements to support the transition to more sustainable urban cultures. Cooling the Commons is a current work in progress for Lopes, with the commons being places, resources, practices and knowledge shared by a community.  The air is a commons;  the makers of air [oxygen] in the form of trees, are commons.  Commoning is the management of the commons and requires establishing protocols for action to ensure that the commons are preserved for wider community benefit. In terms of cooling, an example of privatised ‘coolth’ is switching on an air conditioner which produces carbon gases with contradictory results of trying to keep cool while warming the planet. An example of commons ‘coolth’ would be tree canopies which are critical providers of shade as sun screens / coolth. There is a strong case for designing in time.  ‘Now’ is a period in time and needs to shift to an intergenerational perspective.  Note: Without commons there is no community, without community there is no commons

Dr Marco Amati, Assoc. Professor in International Planning at RMIT University, has a PhD in urban planning and since 2011 has conducted urban forestry research that develops techniques and tools to enable local government to map and record the benefits of the urban forest canopy.  The presentation theme was: Towards legal personhood for urban forests.  Question: Where should all the trees go?  Where there is unregulated urban forest policy, we see death by a thousand cuts, at the very same time that we need to see tree canopy increasing. We can develop exceptionally close relationships  with trees as these two examples demonstrate. At Melbourne Botanic Gardens visitors can participate in Forest Bathing – click on the link for more: Well being phenomenon hitting Australia;   And since the listing of trees as significant ‘beings’ people have been sending emails to particulat trees.  The overwhelming response has exceeded all expectations – click on the link: Melbournes trees have email addresses.  Extending rights to living things we currently regard as objects is one way of re-valuing trees.  What happens for example if we imagine a forest from the perspective of an ecological community?  What is needed, is human beings to represent the interests of the urban forest i.e. adopt ‘legal’ representation for the urban ‘indigenous’ forest – to integrate long or deep time history with the lineage of the forest   In conclusion: Until rightless things receive rights they are vulnerable to being destroyed.  [Editors note: Being without rights can equal being of diminished value, which when up against developer interests often results in the demise of another group of trees to the detriment, 1) of the species living there and 2) of the human community from whom they are taken.

John Douglas, Head Teach Arboriculture, Ryde TAFE, delivered a presentation on how we have become risk averse in our relationship with trees.  The risk of harm by trees is minimal compared with car accidents.  What is needed is common sense when applied to risk minimisation and trees.  Dropping branches is a means by which trees reduce their risk of being blown over i.e. reducing resistance to wind. Yet this is interpreted as the tree being unstable and a factor is applications for tree removals.  What are the real risks as against the perceived risks?  When all these individual removals take place, what is lost in total?  What is the cumulative impact? How can we ensure safety and at the same time ensure tree preservation?

If you missed this conference you may be interested to know what is over the horizon … Announcing an upcoming forum: Trees for Liveable Cities – Delivering effective green infrastructure, 21st February 2020.  To  register your interest log onto:

(1) Willoughby Environmental Protection Association (WEPA)