Page author: Ben Legler
Asperugo procumbens
catchweed, madwort
Close up showing the strongly flattened and toothed calyx.
WTU specimens
Other herbaria

Distribution: Introduced in much of the northern part of the United States; common east of the Cascades in Washington and Oregon

Habitat: A weed of moist soil in fields, roadsides and other disturbed areas, mostly east of the Cascades.

Flowers: May - July

Origin: Introduced from Europe

Conservation Status: Not of concern


Annual herb with weak scrambling stems bearing minute backwards pointing prickles.


Simple, spoon-shaped, lightly hairy.


Small, blue to violet ,with 5 lobes at tip.


4 tiny nutlets.

Identification Notes:

The strongly toothed calyx that encloses the fruits like a clam shell is distinctive; look also for the small blue flowers and backward pointing prickles on the stems.

Accepted Name:
Asperugo procumbens L.

Synonyms & Misapplications:
(none provided)
Additional Resources:

PNW Herbaria: Specimen records of Asperugo procumbens in the Consortium of Pacific Northwest Herbaria database.

WA Flora Checklist: Asperugo procumbens checklist entry.

E-Flora BC: Asperugo procumbens atlas page.

CalPhotos: Asperugo procumbens photos.

USDA Plants: Asperugo procumbens information.

28 photographs:
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