Pennisetum alopecuroides Moudry, black fountain grass

https://davesgarden.com/guides/pf/go/51698/#b

I got some clumps of this about 20 years ago from a neighbor. The pretty seed heads dry out and shed, making plenty of seedlings that are hard to hand pull. And don't wear fleece or knit gloves, as the pointy seeds will stick into it, be hard to remove, and then painfully poke you. Best is to cut off all seed heads before they dry.
But worst of all, this spring I saw that this species now solidly lines one of the local busy two lane roads out of Annapolis. This road has many stretches bordered by woods, a golf course, light business, and a few set-back pricey housing developments. It seems well able to stray far from initial plantings and take up a firm foothold.

Thanks for the warning!