Edge/ Dooryard Knotweed

COMMON NAME: Dooryard Knotweed

OTHER COMMON NAME(S): Many Knees

SCIENTIFIC NAME: Polygonum arenastrum

FAMILY: Polygonaceae

COMMUNITY: Edge

STATUS: Non-native ~ Native of Europe

LIFESPAN: Annual

HEIGHT: prostrate, mat-forming

FLOWERING TIME: July to August

FRUITING TIME: July to August

DISTRIBUTION: Temperate North America ~ Statewide in New Jersey

IDENTIFYING CHARACTERISTICS: Leaves bluish-green, broadly elliptic to oval-oblong ~ Freely branching

GENERAL INFORMATION: Members of this family (Polygonaceae), commonly called the Buckwheat or Smartweed family, include 51 genera and 1,150 species.  Polu means “many” and gonu means “knee” for the swollen stem joints of many species.  Food plants in this family include Buckwheat, Sorrel and Rhubarb. The young shoots of Dooryard Knotweeds, and other species of Knotweeds, may be boiled and eaten as cooked vegetable.  Seeds may be eaten as cereal or ground for flour. Another plant in this genus, Knotgrass (Polygonum aviculare), has been used as a diuretic in Chinese herbal medicine for over 2,000 years.  In the Western tradition, the 1st century AD physician Dioscorides likewise considered the herb a diuretic, as well as a remedy for snake bite.

Please note: While harvesting wild berries/fruit is permitted at Island Beach State Park, visitors must adhere to park regulations at all times and must not damage vegetation or go off designated trails.  This information is presented for educational purposes.