This plant is new to me. It's about 3 ft tall, in a well-shaded area on a river bank in Pennsylvania. It's rough to the touch and looks like a huge parsley-type leaf.
I've lived in PA for about 16 years, only to find tons of new plants and vines that are all imports, and most are extremely invasive. I am identifying as many as I can and am going to make up a report to submit to the city and possibly volunteer for a cleanup job, though it will take an army at this point. I want to see if these plants are medicinal or edible and where they come from.