Included on this list are Norway Maples - we have four of them in our small yard in Cambridge that are now quite large. They grew as weed trees, I let these grow. The good thing is that when my Ash trees died from some disease they were there to replace them. One of the properties of Norway Maples is that the leaves don't finish dropping until late in December which is why my gutters still have too much junk in them.
Then for Gloucester there is:
knapweed, which is taking over a spot of our front meadow,
Oriental bittersweet that is busy winding itself around trees with a constant need to cut them - since they spread underground via the root system and via seeds they are everywhere,
various kinds of woody honeysuckle - it flowers for a short time, but mostly supplies greenery; these aren't too hard to remove since the roots are not deep.
Also I see on the list multi-flora roses, the tansy that isn't the same as our invading tansy, and wild blackberry; oddly I didn't notice any sheep sorrel but it stays small and doesn't seem to crowd out stuff - much.