Douglas' Knotweed

Polygonum douglasii Greene

Buckwheat family

Plant Type
Forb/herb
Life Cycle
Annual
Mature Height
32 inches
Flower Color
White, Pink, Green
Bloom Time
Late Spring, Early Summer, Mid Summer, Late Summer, Fall

Ecosystem & Wildlife

Pollinators Bombus; Butterflies; Larval Host (Butterfly)
Larval Host Epidemia helloides, Epidemia mariposa, Epidemia nivalis, Lycaena nivalis, Lycaena nivalis browni

Native Range

  • CAN:  Alberta, British Columbia, Manitoba, Ontario, Québec, Saskatchewan, Yukon
  • USA:  Arizona, California, Colorado, Idaho, Iowa, Michigan, Minnesota, Montana, Nebraska, Nevada, New Hampshire, New Mexico, New York, Oregon, South Dakota, Utah, Vermont, Virginia, Washington, Wyoming
  • MEX:  Mexico Northwest

Regional Native Status: L48 (N), CAN (N)

State-level native status is based on data available through Plants of the World Online. Regional Native Status comes from the USDA Plants Database. For more detailed native status information, please refer to BONAP.

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