I did a walk here during the ULI event last week. The tour leader was involved in creating this area. Mentioned they are mystified why the trees are all of sudden suffering. They are investigating.
I've discussed here what affected the trees at least 2 of the last years. (see post on Cottony Maple Scale, below)
It looks like many of the maple trees on the promenade are sick and dying I feel like this is a constant refrain for the trees on the waterfront, and I don’t understand why. It’s deeply upsetting.
urbantoronto.ca
That said; the scale is not typically lethal, so there are likely other factors at play.
There is a correlation, timing wise, between the underwater works that have been carried out the last 2 years next to the promenade and a decline in tree health, this could be a coincidence or there may be some relationship.
The trees have reached a very mature state (size) at this point, which does make me wonder about soil volumes, root girdling, access to moisture, and nutrients. Larger trees need more everything to thrive; that said, the typical response
of many species to under nourishment or finite moisture, once established, is to just level off in growth to match the resources available.
That's how you get tiny little cedars growing out of cracks on the side of the Escarpment. They grow as much as the moisture and nutrients and root growth space allow and then stop.
The one thing I will say with more certainty though is this, the decline in tree health here really illustrates the risk of going with an allee of a single tree species for any distance. If something goes wrong, all the trees are at risk, this is most particularly true when all of the trees are clones as is this case here.
He also pointed out a couple of trees next to a condo (Aqualina I think) that are shorter than the others. Seems someone living in the condo was concerned about losing their view so they cut off the tops! I'm talking 20 feet up.
I hope that person has been identified and charged.
