Speaking to Junctionist's comment regarding the London plane trees preforming well, I think the jury is still out. Some of them have really been struggling. That's why I commented that I hope some of the trees can really take root and grow larger so that they can provide some shelter from the harsh conditions of Bloor street (strong drying winds and poor light levels).
Someone with tree knowledge may be able to answer my question but isn't the London Plane a hybrid of the American Sycamore tree? Wouldn't it then be ironic that we would be planting a tree from North America the English engineered for England but now planted back in North America?
From Wikipedia:
Platanus × acerifolia, London plane, London planetree, or hybrid plane, is a tree in the genus Platanus. It is usually thought to be a hybrid of Platanus orientalis (oriental plane) and Platanus occidentalis (American sycamore). Some authorities think that it may be a cultivar of P. orientalis.
... in my work w/urban forest restoration, I work w/native species, and have a bias in that direction, though I don't really object to London Planes (they aren't thought to be overly invasive here.)
I do, however, have a problem with using only one species (any species) for the entire 1km + stretch of road.
See Emerald Ash Borer and decimation of our Ash trees, or Dutch Elm disease obliterating most elms.
Choosing only one species makes them extremely vulnerable to any disease or pest that may come along and could wipe out an entire landscape all at once.
At a minimum I would expect to see 2 different Genus and 4 diff. species over an area this size (the guidelines that urban foresters use would suggest greater diversity than that); but I understand the landscaping impulse to choose a 'pattern' or shape and repeat it.
Still, alternating the species either very other planter or every even other block would have been very sensible.
I might add, I can think of a host of native species that I think would look better, and do just fine in these growing conditions.
Bur Oak, or even Red Oak would have done very nicely; then varying that up w/silver maple, giving you bright yellow and orange/red leaves in the fall........