Jane - PA has some amazing trees. We have a beautiful park near me that has all the trees marked with their 'official' names. A Boy Scout troup came in and researched each tree and then had a plaque made for each tree, identifying them.
I have two of the only trees on our entire block. Raking the leaves up each year is a bit of work, but the beauty of my 100 foot Maples is worth all the work.
My family bought a tree is Elliott's memory and had it planted in Rothrock State Park (in PA). I loved that they did that for my E. I love trees too...and I am sure that you gals will have fun researching!