What Blight is This?

I had occasion to cycle along the canal several times this weekend, from Dows Lake to the NAC end, using the NCC bike paths.

I was really struck by how many trees have dried up, brown, crunchy leaves. First noticed on the south side of the canal, from Bronson to east of Bank, whole swaths of tree branches, entire sides of trees, exhibit dried branches. I presume it is not from lack of water.

Then some became apparent on the north side of the canal too, along the Golden Triangle area. Once looking, they were frequent. Usually on mature trees.

This week, I cut down one of my back yard peonies right to the ground, and threw out the leaves and stems which had, seemingly overnight, gone spotted and brown. A virus, a friend and better gardener told me, put them in your regular garbage and not leaf collection or composting.

Anyone know what blight this is, and whether the trees and shrubs will come back next year or are permanently dead?