Stinkwort is an invasive that showed up at Rockville in 2014. By 2016, it was the main plant growing in the meadow area across from the Quarry. The plant smells like camphor. I have a friend who named the weed 'Chicken Shade Bush' because his chickens like it. Works for me!
That's a lot of Stinkwort in a very short period of time.
Found more Stinkwort at the Green Valley entrance to the park in 2019.