Nodding Smartweed (Polygonum lapathifolium) also known as: Curlytop Knotweed, Curltop Ladysthumb and Pale Smartweed  Division - Magnoliaphyta Class - Magnoliopsida Subclass - Caryophyllidae Order - Caryophyllales Family - Polygonaceae Genus - Polygonum      Taxonomic List List by Scientific Name List by Common Name |