Interesting! I have been noticing that the Norwegien? Bittersweet that I have trained to cover my HOT driveway as a beautiful canopy is EVERYWHERE!! We drove from New Hampshire to Ontario and Alot of the trees on the sides of the highway were all choked out from the bittersweet.....I feel alittle guilty for using it but I keep it trimmed and do not let it go to seed.It grows so FAST!
I am almost positive it is >. It was on one of the local tv stations in regards to it being one of the most evasive plants.