Hemizonia congesta subsp. lutescens
Photo: parent species Hemizonia congesta · (c) Bruce Homer-Smith, some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Annual · Native
Hemizonia congesta subsp. lutescens is a native California annual in the Asteraceae family, recognized by 6 sympatric subspecies. Key diagnostic: yellow ray flowers vs white in others.
Congested tarweed is a California native annual found in southern Northern Coast, southern Northern Coast Ranges, northern Central Coast, and northern San Francisco Bay area grasslands, barrens, and openings in chaparral and woodland, often on serpentine at elevations below 500 meters. Flowering from April to December, this plant produces yellow flowers with purple-veined ray flowers in compact clusters. Growing with short to shaggy hairy stems that can be glandular, it forms delicate panicle-like clusters of flower heads. Its leaves are short-hairy, somewhat shaggy, with distal leaves becoming increasingly glandular. The fruit is relatively narrow, measuring less than two-thirds its length.
Identification and appearance
Key characters: 6 sympatric subspecies. Key diagnostic: yellow ray flowers vs white in others
Habitat and range
Habitat: Grassland, barrens, openings in chaparral and woodland, often on serpentine
Elevation: < 500 m
California counties: Sonoma, Marin, Alameda, Contra Costa, Napa, Solano, Mendocino, Monterey
Bloom period
Hemizonia congesta subsp. lutescens blooms Apr-Dec.
How to tell it apart
vs Deinandra: Hemizonia rays often purple-veined beneath; Deinandra rays pure yellow without veining.; vs Madia: Hemizonia has paleae throughout disk; Madia has ray fruits enclosed by phyllaries.; vs Calycadenia: Hemizonia rays shallowly lobed; Calycadenia rays deeply split into spreading lobes.; vs Holocarpha: Hemizonia lacks pit glands on stalks; Holocarpha has distinctive pit-gland-tipped stalk bracts.; vs Anisocarpus: Hemizonia has chaff throughout flower disk; Anisocarpus typically lacks chaff scales.
Frequently asked questions
Is Hemizonia congesta subsp. lutescens native to California?
Yes. Hemizonia congesta subsp. lutescens is native to California (recorded as native).
When does Hemizonia congesta subsp. lutescens bloom?
Hemizonia congesta subsp. lutescens blooms Apr-Dec.
Where in California does Hemizonia congesta subsp. lutescens grow?
Hemizonia congesta subsp. lutescens occurs in Sonoma, Marin, Alameda, Contra Costa, Napa, Solano, Mendocino, Monterey, at elevations of < 500 m.
What plant family does Hemizonia congesta subsp. lutescens belong to?
Hemizonia congesta subsp. lutescens is in the Asteraceae family, genus Hemizonia.
What habitat does Hemizonia congesta subsp. lutescens grow in?
Hemizonia congesta subsp. lutescens grows in Grassland, barrens, openings in chaparral and woodland, often on serpentine.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-01
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.