Could this be mulberry weed?
This appeared in our yard in two places - very fast growing and I don't know what it is. A friend suggested it might be mulberry weed. I looked it up and it doesn't look exactly like it but very close. What do you think? Is it useful for anything?
Beaver County Pennsylvania
Based on the photos you submitted it appears to be Mulberry Weed or hairy crab weed (Fatoua villosa) (Thunberg) Nakai which is an invasive exotic Asian species from the Mulberry family (Moraceae). It is characterized by papery, heart-shaped, alternate leaves and has densely pubescent (hairy) stems. The flowers are dense, light green cymes (clusters) with no true petals, and seeds that are forcibly expelled. It should be removed and placed in the trash and not composted. The following link provides additional information. http://extension.udel.edu/factsheets/mulberry-weed-fatoua-villosa/
Thank you, Rick. Even since I posted this photo, it has spread a lot at the same site and even jumped to a different part of my garden. I have disposed of it. Thank you!