LariAnn said: They do not invade balanced or pristine natural ecosystems, but rather (human) disrupted environments.
That's wishful thinking, frankly. There are a multitude of exotic plants that are fully capable of invading intact native ecosystems and severely disrupting how they function (e.g. leafy spurge, spotted knapweed, phragmites, purple loosestrife, sericea lespedeza, caucasian bluestem, saltcedar, giant knotweed, whitetop, the list seems endless). It never ceases to surprise me how dismissive some gardeners are of the very concept of invasiveness. I think it often boils down to the simple fact that they want to be able to grow whatever they like, regardless of the consequences for the rest of us. That's disappointing. You would think gardeners, of all people, would have more regard for the natural world than that.
