These plants love water and will outgrow anything in their way including blacktop. Another location on River road, Blacktop had been laid on top of dormant plants and the Knot weed simply grew up through the blacktop.

River Road, Endwell, NY
June 8, 2012
iPhone 4S

Tri-Cities Airport on the road to the creek past the last hanger, Endicott, NY
September 10, 2012
iPhone 4S