[Northern Light]

Since I've seen a few requests for a thread just on Toronto's Trees, I'm making this one.

I expect questions will still arise in various specific project threads, but if people want to have an intensive tree-related discussion, this will be a good spot.

I'll post this article from 2016 to get us started.

"An urban forest in crisis"

https://www.theglobeandmail.com/new...important-for-torontoscanopy/article31295396/

 

[Northern Light]

This article is also on point.

Protecting Toronto’s downtown trees from the hardships of urban life

https://www.theglobeandmail.com/new...-the-hardships-of-urban-life/article25259956/

 

[steveintoronto]

Excellent articles linked above!

Most recently, this one by Christopher Hume impressed me:

Why Toronto needs all the trees it can get
By CHRISTOPHER HUMEStar Columnist
Mon., July 9, 2018

When all else fails, there are always trees. When global warming has turned the city into a melting zone, there are always trees. When planners have turned the city into an unsightly mishmash of intentions and outcomes, there are always trees. When developers have filled the city with buildings hostile to every civic and human need, there are always trees.

But in vast swaths of Toronto, there aren’t always trees.
[...]

https://www.thestar.com/opinion/sta...y-toronto-needs-all-the-trees-it-can-get.html

 

[TheTigerMaster]

I wish there was more awareness about the importance of street trees. Almost universally, people seem to think that their main purpose is to stand there and look pretty. People don't get that street trees are vital public infrastructure that provide everything from indoor air conditioning, to flood protection.

 

[Northern Light]

I wish there was more awareness about the importance of street trees. Almost universally, people seem to think that their main purpose is to stand there and look pretty. People don't get that street trees are vital public infrastructure that provide everything from indoor air conditioning, to flood protection.

An article on point for you, you may wish to share.

Urban Street Trees: 22 Benefits - Specific Applications

http://www.walkable.org/download/22_benefits.pdf

 

[steveintoronto]

As a slight aside to the thread surmise, as much as the present humid and wet weather is cramping my distance cycling (you can't plan a trip if you can't depend on the weather), the rain is welcome relief for areas to the north and northeast/northwest of Toronto. Peterborough and Guelph are two examples of where things are/were seriously browning out. Guelph is even rationing water for hosepipes at this time.

Somehow, Toronto and Hamilton area are staying remarkably green and lush for this time of year. The green canopy in Toronto is endearing when it's extant, devastating when it isn't.

 

[Johnny Au]

Looking at some photos of Toronto from high elevations, it looks as if parts of Toronto were covered in a forest.

It helps moderate temperatures and reduce runoff to some degree. Oh, and plenty of shade too.

 

[44 North]

The city should plant more catalpa trees. Discovered it a couple years ago on the shores of Lake Erie and was fascinated. Has these mammoth lush leaves and long dangly seed pods. Took some pods, planted them. It's a nice tree I could get used to. Have spotted some in parks around the city since then but wonder if it could be a good street tree too. Tremendous shade offered. Not exactly native, but close enough I think it's okay (it's Carolinian and so is TO).

 

[narduch]

Looking at some photos of Toronto from high elevations, it looks as if parts of Toronto were covered in a forest.

It helps moderate temperatures and reduce runoff to some degree. Oh, and plenty of shade too.

If I remember my high school geography correctly, before this area was settled it literally was all forest.

 

[Northern Light]

If I remember my high school geography correctly, before this area was settled it literally was all forest.

Predominantly.

There were small bits of meadow, fen and bog; and there were some fair sized wetlands; the most notable of which were coastal along the Lakeshore, in the vicinity of Ashbridges Bay, and also at the mouth of Highland creek.

Thee current analysis revealed that prior to European settlement
(c.1800), 2,026,591 ha of wetland were widely distributed throughout Southern Ontario. By 2002, 560,844 ha remained, an
overall reduction of approximately 1.4 million ha or 72% of the pre-settlement wetlands. Between 1982 and 2002, an additional
3.5% (70,854 ha) of the pre-settlement wetlands in the study area were lost, an average loss of 3,543 ha per year.
This is equivalent to the loss of approximately 354 large 10 ha wetlands per year for the last 20 years.
The decline in wetlands since settlement has been most drastic in south western Ontario, parts of eastern Ontario, Niagara and the Toronto area, where over 85% of the
original wetlands have been converted to other uses. Built-up lands, impervious and pervious, were a signicant factor in the loss
of wetlands within the Golden Horseshoe. Outside of the Golden Horseshoe other uses include agricultural lands (including
field, forage crops, specialty crops, nurseries, rural properties and idle lands), urban brown fields hydro right-of ways, edge of
transportation corridors and clearings within forests.

per:

http://www.ducks.ca/assets/2010/10/duc_ontariowca_optimized.pdf

 

[MrSocky]

The city should plant more catalpa trees. Discovered it a couple years ago on the shores of Lake Erie and was fascinated. Has these mammoth lush leaves and long dangly seed pods. Took some pods, planted them. It's a nice tree I could get used to. Have spotted some in parks around the city since then but wonder if it could be a good street tree too. Tremendous shade offered. Not exactly native, but close enough I think it's okay (it's Carolinian and so is TO).

Although I am in agreement with the beauty of its large heart shaped leaves and showy white flowers, its brittle wood in ice/wind storms and messy pods make it a hard sell as a "street tree" in the purest sense to many homeowners. It is best preserved for large parks away from structures and overhead wires. One only has to look at the plague of silver maples on Toronto streets during wind storms to understand not only the hazardous but also economic reasons for avoiding brittle trees. My family often jokes that it is not a real storm unless a silver maple crushes some unlucky car, never mind the financial burden on utility companies. It is obviously inevitable that trees will fall down at some point, but it is negligent to knowingly plant species that are especially prone to it.

 

[Northern Light]

Although I am in agreement with the beauty of its large heart shaped leaves and showy white flowers, its brittle wood in ice/wind storms and messy pods make it a hard sell as a "street tree" in the purest sense to many homeowners. It is best preserved for large parks away from structures and overhead wires. One only has to look at the plague of silver maples on Toronto streets during wind storms to understand not only the hazardous but also economic reasons for avoiding brittle trees. My family often jokes that it is not a real storm unless a silver maple crushes some unlucky car, never mind the financial burden on utility companies. It is obviously inevitable that trees will fall down at some point, but it is negligent to knowingly plant species that are especially prone to it.

I've only noticed Northern Catalpa as a street tree in one location, where there are 4, in extended planters (3m long, tree in the middle, 2ft off ground).

Their first year was brutal, but they made it.

Since then all 4 have done well.

They are in near ideal conditions and don't have wires overhead.

I haven't seen Catalpa often enough to judge the brittleness issue.

But its a legitimate concern.

In Maples, I think Norway has been more of a problem than Silver.

But Silvers, if not pruned properly have a tendency to go very multi-stem, which makes them a greater risk for failure of limbs.

The Catalpas I've seen show strong single-stem style growth.

Is that the common natural form (I'll have to do some research); often varietal or hybrid choice is key for such things.

I haven't noticed what their salt tolerance is either. I will research and report back.

 

[condovo]

I love this thread. It's so interesting.

 

[Northern Light]

So, as promised, I've been reviewing Northern Catalpa.

There does seem to be a consensus on its brittle-ness and being prone to losing branches during storms.

That does seem an odd trait for a street tree.

What I'm not yet clear on is if this trait risks the heaviest limbs as much as the finer branches.

The former being dangerous, the latter being only messy.

I can see why the City is interested in it.

It shows a tolerance for moderate shade, for drought, for compacted soils and even standing water.

Its salt tolerance, however, does not appear to be as pronounced. Not hyper-sensitive to salt, but not high-tolerance either.

http://puslinchnaturallynativetrees.ca/the-northern-catalpa-tree/

http://www.mortonarb.org/trees-plants/tree-plant-descriptions/northern-catalpa

From Morton, linked above.

Curiously, historically, not even Carolinian.

It appears to have been native in recent centuries to a small area in the central Mississippi valley; yet is hardy in much colder conditions.

Some suggestion that the tree historically was further north, prior to the last ice age and retained genetic tolerance for colder weather.

 

[gabe]

Good news!!!! This would have been a huge loss if it got chopped down.

Council approves plan to buy North York house to save what may be Toronto’s oldest tree

Toronto council has given city staff the go-ahead to negotiate the acquisition of a North York house that is home to a 350-year-old oak tree — believed to be the oldest in the city.

https://www.thestar.com/news/gta/20...to-save-what-may-be-torontos-oldest-tree.html