Japanese Knotweed

Common name: Japanese Knotweed
(Japanese Bamboo)

Scientific name: Polygonum cuspidatum

Dimensions:
  Flower: About 1/8" (3 mm) long
  Plant height: 3-10' (90-300 cm)

Blooming period: August-September

Habitat: Fields, thickets, roadsides, weedy places

Description: Greenish-white flowers in branching spikes, mostly arising from the axils; clusters 2-5" (5-12.5 cm) long; 5 sepals, 5 petal-like lobes, no petals. Flower stems large, hollow, jointed. Male and female flowers on separate plants. Leaves 4-6" (10-15 cm) long, rounded or ovate, short- pointed with smooth margin. Large bushy plant that escaped cultivation as ornamental. Overall appearance seen as bamboo-like. Smartweed family. (August 19)