Leaf Key
What I would recommend is to go and collect samples sometime before Fall, press them in newspaper and then spend some time identifying everything. It really helps to get a feel for what you have. It sounds daunting, but with that leaf key, you should be able to get through your samples in an afternoon.
I also have this:
It's a little turgid, and sometimes you find yourself trying to remember ovoid vs. ovate vs obovate, and your brain freezes up, but it's really fun. I did this with #1 and #2 sons when their schools asked for a leaf collection. I'm still waiting for #3 to need his-- still have my leaf press.

