Invasive or new native?

When I was reporting in California over the summer, a conservation official mentioned the possibility of "new natives:" invasive plants that humans introduced centuries ago and are now part of the landscape.  Like most immigrants, they "take over" areas and bear the brunt of the blame for all kinds of ecological problems — but they're here, and it

This Yale E360 video "In Drought-Stricken Southwest,A War Against an Invasive Tree" captures the nuance between resistance and acceptance. Is it right that politicians aggressively fight the the tamarisk tree, or salt cedar, when scientific evidence shows that it's not responsible for water loss? What about the flycatchers who build homes in the trees' branches?

This is a good time for Nick to chime in.