Taxon  Report   4065 
Hemizonia congesta  DC.
hayfield tarweed
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 
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 Plant Characteristics
 and Associations

Bloom Period
Hemizonia congesta
© 2007 Neal Kramer
Hemizonia congesta
© 2009 Neal Kramer
Valley Grassland, Northern Coastal Scrub, Foothill Woodland, Southern Oak Woodland
Genus: Hemizonia
Subspecies and Varieties:
Hemizonia congesta ssp. calyculata
Hemizonia congesta ssp. clevelandii
Hemizonia congesta ssp. congesta
Hemizonia congesta ssp. lutescens
Hemizonia congesta ssp. luzulifolia
Hemizonia congesta ssp. tracyi
Distribution by County 

Add an Observation of  Hemizonia congesta

Name Status:
Accepted by TJM2 + PLANTS + JM93
 Information about  Hemizonia congesta  from other sources:

Nursery / seed vendor availability from CNPLX
This plant is available commercially.

Photos on CalPhotos / Google Images

website references on Google

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. on the
International Plants Names Index

Search (Flora of North America)

Search the Lady Bird Johnson Wildflower Center

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]. 2015. Berkeley, California: The Calflora Database [a non-profit organization].
Available:   (Accessed: Aug 28, 2015).

The information on this page comes from diverse sources. None of the links are sponsored.

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