I think they count. In my last town I had too many trees and I cut some palm trees down. After that my town rating was better than before. Because of that, I would be pretty sure that they count.
Same for me, I'm far from having 110 trees and I've got my perfect town since july or august 2013. I don't think you really NEED 110 trees, it's more the spot where they are, there should be enough space between each tree like 2-3 and have "many" flowers and have at least 5 public-work projects in your town^^ I believe I got the perfect town because my town was more like a flower field than a town..XD
Aside from flora, you'll also need projects. Plants vs. projects needs to be balanced.
I'm not sure if the amount of patterns on the ground affects it.