My old family homestead is in Glenn Dale, MD, which is also home to an old US Plant Introduction Station. Basically, a government farm where they did experiments on plants. And, home of the Bradford Pear. As a result, the surrounding countryside is full of mutations that Mother Nature never intended.
For instance, the Bradford Pear is not supposed to bear fruit, nor be able to reproduce. And it won't, with other Bradford Pears. However, it will cross pollinate with other types pears, and their offspring are these nasty, mutated looking things with thorns long enough to pierce the sole of a Chuck Taylor, and no doubt many other shoes as well. The damn things really take over, too. They do bear fruit, these small things a bit bigger than a grape, that actually do taste like a pear. I don't know if they're considered invasive, to the point that they crowd everything else out, but they certainly give the other greenery a run for its money! On the plus side, they are really pretty in March/early April, when they bloom.
Other things that seemed really invasive in Glenn Dale were honeysuckle bushes, which seemed to spread by both seeds AND runners. Oh, and Japanese knotweed. I also learned, about 22 years ago, how a Locust tree will also send out runners. There were three in my grandmother's yard, that they had taken down. Suddenly, they started sprouting up all over. Where they were actually IN the yard, they just got run over with the mower, but along the property line where there's a ditch, we let them grow up. And damn those things grew up fast!
I had one taken down at my new place in 2021, in preparation for a new garage construction. I wanted to clear back any trees that were overhanging, or would have the potential to as they grew. Plus, Locusts tend to break easily in wind/ice storms. Ever since I had that sucker taken down, I've been fighting with its offshoots, some of them a good 50 feet from the original trunk!
I've seen Japanese knotweed along the road, within a few miles of my current house in Crownsville, MD. But thankfully, haven't found any on my property. That stuff looks kind of cool, at first. Sort of an exotic, almost pre-historic look about it. But man does it take over! Also, thankfully, no wild honeysuckle bushes (just the vines, which don't mind. And none of those damn thorny mutant pears!
Oh, bittersweet vines. I had those at the old place, and the new place as well. Constant battle, and those suckers eventually will get big enough to choke off some good-sized trees.