Taxon  Report   4065 
Hemizonia congesta  DC.
Hayfield tarweed
Hemizonia congesta
© 2010 Vernon Smith
Click on a photo to see it bigger.
Hemizonia congesta
© 2015 John Doyen
Hemizonia congesta
© 2015 Vernon Smith
Hemizonia congesta, a dicot, is an annual herb that is native to California and is also found outside of California, but is confined to western North America.

Interactive Distribution Map

Observation Hotline
(observation details + photos)

point, line, or polygon

Plant Characteristics
and Associations

Bloom Period
Hemizonia congesta
© 2015 Vernon Smith
Valley Grassland, Northern Coastal Scrub, Foothill Woodland, Southern Oak Woodland
Distribution by County 

Add an Observation of  Hemizonia congesta

Name Status:
Accepted by TJM2 + PLANTS + JM93
More information about  Hemizonia congesta
Nursery / seed vendor availability from CNPLX
This plant is available commercially.
Landscaping information from Calscape
Photos on CalPhotos / Google Images
UC Integrated Pest Management Weed Photo Gallery
(profile of this plant as an agricultural weed)

Jepson eFlora

Records from the Consortium of California Herbaria

Original Publication citation (ITIS)


Search the International Plants Names Index

Search (Flora of North America)

Search the Lady Bird Johnson Wildflower Center

website references from Google

Suggested Citation
Calflora: Information on California plants for education, research and conservation,
with data contributed by public and private institutions and individuals, including the Consortium of California Herbaria.
[web application]. 2018. Berkeley, California: The Calflora Database [a non-profit organization].
Available:   (Accessed: Feb 25, 2018).

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