Polygonum pensylvanicum

Common Name: 
Pennsylvania smartweed, pinkweed, pink knotweed
Scientific Name: 
Polygonum pensylvanicum L.    syn.  Persicaria pensylvanica
Family Name: 
Polygonaceae - Smartweed or Buckwheat Family
Identification Notes
Life Cycle
native annual, reproducing by seed
Stems
upright, smooth, branching, swollen nodes, ocrea (papery or membranous sheath) at nodes
Stem of Polygonum pensylvanicum
Leaves
alternate, lanceolate to elliptic, tip pointed and roundish base, hairless, frequently with purple blotch, short petiole
Leaves of Polygonum pensylvanicum
Leaves of Polygonum pensylvanicum
Flowers
bright pink to rose sometimes white, petals absent; clusters form short terminal spike
Flowers of Polygonum pensylvanicum
Leaves of Polygonum pensylvanicum