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Polygonum douglasii - Douglas' knotweed

Scientific Family
Polygonaceae
Synonyms
Polygonum buxiforme, Polygonum emaciatum, Polygonum montanum
Plant type
Forbs and Subshrubs
Origin
Native
Lifecycle
Annual
Height
To 32 inches
Riparian
No
Erect, wispy plant with narrow green leaves and small, greenish-white flowers along the top of the stems.
Abruptly reflexed (bent) flower stalks, stems that do not twine, flowers scattered along the stem and erect stems distinguish this species from others in this genus.

Habitat

Dry, often disturbed places, rock outcrops, mountain meadows, sandy ground.
Plant Community
Pinyon Juniper Woodlands
Montane Conifer Forest
Interior Chaparral
Grasslands
Disturbed Areas
Desert Scrub
Low elevation
1000
High elevation
10000

Flower Characteristics

The small flowers are to 1/8 inch long. Flowers are axillary and terminal.
Flower color
White to greenish or reddish
Flower shape
Regular
Tubular
No
First bloom month
June
Last bloom month
October
Flower clusters
Elongated

Leaf and Stem Characteristics

The green stems are erect, some branched, 2 to 32 inches long. The narrow, green leaves are 1/2 to 2 inches long.
Leaf type
Simple
Leaf color
Green
Leaf shape
Narrow
Leaf margin
Smooth
Leaf attachment
Alternate
Leaves clasp
No
Leaf hairs
None
Spines
No

Fruit and Seed Characteristics

Fruits are shiny and to 3/16 inch long.
Fruit type
Achene
Fruit color
Black