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How to Manage Pests

Identification: Weed Photo Gallery

Sowthistles

Scientific name: Sonchus spp. (Family Asteraceae)

Life stages of Sowthistles top picture bottom left picture bottom right picture

Click on image to enlarge

DESCRIPTION:
Sowthistles are among the most common weeds in farms and gardens in spring. They can be seen at any time of the year in mild climates, but commonly germinate from late fall to early spring with the highest numbers of mature plants present in spring and early summer. The sowthistle seedling has markedly stalked, almost spoon-shaped seed leaves, rounded at the tip. The seed leaves often have a grayish powdery bloom, but later leaves have only a few hairs. Later leaves have prickles or teeth along the margin with a winged stalk on the third or fourth and later true leaves. Flowers are yellow and mature into fluffy white seed heads. Stems are hollow and exude a milky juice when cut open.

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/sowthistles.html revised: March 11, 2008. Contact webmaster.