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How to Manage Pests

Identification: Weed Photo Gallery

Pale smartweed

Scientific name: Polygonum lapathifolium (Buckwheat Family: Polygonaceae)

Life stages of Pale smartweed Swollen stem nodesMature plantFlowers

Click on image to enlarge

DESCRIPTION:
Pale smartweed is an annual broadleaf weed that grows in moist soil. Plants may be erect, up to 4 or 5 feet (120 - 150 cm), or creeping with weakly, ascending stems. Stems are red and swollen at the nodes (joints in stem). The leaves are long and narrow, tapering at the tip with whitish undersides. Flower clusters are long (1 - 3 inches, 2.5 -7.5 cm) and cylindrical, densely packed, and droop from stalks. They range in color from white to pale pink. Individual flowers never open.

Flowers of the closely related ladysthumb, P. persicaria, are borne in shorter clusters that are brighter pink and more erect than that of pale smartweed.

Broadleaf ID illustration.


Statewide IPM Program, Agriculture and Natural Resources, University of California
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For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See How to manage pests, or in the U.S., contact your local Cooperative Extension office for assistance. /PMG/WEEDS/pale_smartweed.html revised: November 17, 2008. Contact webmaster.