Family: Polygonaceae
erect knotweed
Emmet J. Judziewicz
from USDA Plants website
University of Wisconsin-Stevens Point, Robert W. Freckmann Herbarium (UWSP)
Etymology: Polygonum: derived from the Greek words polys, "many," and gonu, "knee or joint," hence "many joints" because of the thickened joints on the stem
Plants: erect to sprawling, annual, up to 20" long forb; stems branched, nodes becoming brownish and cut
Leaves: alternate, bluish-green, small, flat, narrow, oval to elliptical with a rounded tip, jointed at the base
Flowers: yellow to green, 5-parted, 1/8" long, urn-shaped, petals and petal-like sepals joined at the base
; inflorescence small clusters from the leaf axils
Fruits: yellow to tan, dry seed
Habitat: disturbed sites
Plants: erect to sprawling, annual, up to 20" long forb; stems branched, nodes becoming brownish and cut
Leaves: alternate, bluish-green, small, flat, narrow, oval to elliptical with a rounded tip, jointed at the base
Flowers: yellow to green, 5-parted, 1/8" long, urn-shaped, petals and petal-like sepals joined at the base
; inflorescence small clusters from the leaf axilsFruits: yellow to tan, dry seed
Habitat: disturbed sites
Floristic Rating: Coefficient of Conservatism = 0, Wetland Indicator = FAC USDA Plants Database: Federal Distribution and detailed information including photos
from USDA Plants website
