An new perennial weed to watch out for in Connecticut gardens is mugwort (Artemisia vulgaris) aka Chrysanthemum weed. While not yet on the CT Invasives Plant list it has very invasive tendencies.
I had some experience with it in my NY garden. It was a “volunteer” with very pretty foliage so I let it go to see what it would do. Yikes! One or two seasons was all it needed to take over the bed. It spreads by rhizomes and once it digs in, it takes constant digging and vigilance to eradicate.
I have a relative, Artemisia ludoviciana ‘Silver King’, in my garden now. It came as a hitchhiker from a plant “donation”. Luckily it is in a bed with day lilies (they can fight it out) and hemmed in by a concrete path and lawn. It provides a nice silver accent and dries well.
Contact CIPWG if you see mugwort in natural areas.