Hmm, parks, trees, Yes there is a lot of them downtown if your not too lazy to go look, along Bay Street just north of College, all the way to Bloor, there are little spots of Greenery and bigger parkettes too, I walk along there often with my friends in the summer, also another bright spot is Wellesley, just east of the subway station, a couple of nice spots, as well as Bleecker & Wellesley, by the new(ish) community center, lots of green grass around there, also walking up Sherbourne, from Dundas to Bloor, many greenspaces, lots of nice older trees, and this comes from a legally blind person! lol, along bloor near Castle Frank Station is nice too.
I Love Toronto for just that, lots of trees, parkettes and intresting spots.
I come from Hamilton origianlly, we have Gore Park there, really just a widend boulavard at spots, but its a nice treed spot in the heart of downtown. the mall near there even has a rooftop plaza with lots of greenspaces too and lots of trees.