I don't know your varieties, but there's a plant in my community garden that had basically green stalks. I thought I'd give it a last chance before I killed it: khaki stewed rhubarb is not a good look! I pulled off nearly all the stalks, leaving basically just the crown and shoots. The new growth is really red, so I'm assuming it was a cultural, rather than varietal issue. YMMV...

Ditto above. I am quite familiar with these trees and had 4 large Norways removed from my lot, with 1 huge one remaining, which is the biggest. :( They are extremely weedy, and have started to invade the small woodland areas in the neighborhood. I cut, poison, and girdle these suckers at every opportunity and am still debating removing the last big one which is indeed a beast ($$$). Acer platanoides 'Crimson King' is a very common cultivar and may be less aggressive than the species. However, since it is a Norway, I would trash that sucker and plant a much nicer native tree instead (I hate Norways too).

I dunno. Bark could be red maple. Something is wrong with the leaf or samara shape I THINK when I zoom in. Then again my red maple's leaves are a bit rounded....Why isn't every other one on the street doing the same? If you cannget one OP, I request a close of of the red leaves or seeds.

I agree with slug or snails. Especially if you never see any insects actively doing it. Youtube how to control them. You can sprinkle around something but I forget what it is called that will repel them from the base of your plant. They hate copper and I use tall raised beds with treated wood so I hope that repels them for me.