A local VEPP (Very Experienced Parks Person) emailed me in response to my post below.
Here's what he had to say:
"I guess I have always thought, as a Horticulturist, 'horses for courses'. Some environmentalists are too focused. They complain that things like London Plane are "not native" - but give me another tree that will deal with paving and bitumen over its roots and still thrive in hot conditions? Would they prefer half dead natives you spend twice as much time and water on to try to get established? Isn’t the whole plan to beautify and cool down an area making it more habitable? I like natives as well, but it depends on location. I noticed a couple of the Weeping Peppermints at Elizabeth Quay are dead or dying.This is a multi-million dollar project and yet you still have losses!* Things change in horticulture. We no longer plant Fraxinus or Box Trees on our verges as they don’t seem to cope with the reduced rainfall. We have lost many mature trees. Isn’t the definition of insanity doing the same things and expecting the results to change? If tree A isn’t working, shouldn’t we try tree B or C to get a better outcome? My 10 cents worth."
Thanks VEPP - I reckon that's pretty good value for 10c :)
And I also think, as VEPP implies, it's simply time to get over this native vs exotic thing and start realising that urban trees are really "green infrastructure". There was a very telling comment in the last presentation of the conference. The presenter put up the street tree list of a local council (you know, the ones we used to give to residents and say "here, choose from these") and said "thank goodness most councils have moved away from this and instead choose the right tree for the right location regardless of where it comes from." A few people would have been squirming in their seats I reckon ;)
* I was speaking to a local VEAP (Very Experienced Arbor Person) who expressed his disappointment that sound arboricultural advice from some top consultants was not followed on this project