Ambrosia chenopodiifolia
San diego bur-sage, San Diego bur-sage, San Diego bur-sage
Photo by Chez Brungraber
Family: Asteraceae · Type: Shrub · Native
Conservation status: CNPS 2B.1
Ambrosia chenopodiifolia (San diego bur-sage) is a native California shrub in the Asteraceae family, recognized by woolly burs and small rounded leaves.
San diego bur-sage is a rare (CNPS 2B.1) California native shrub found in southern coastal Southern California in southwestern San Diego County's coastal scrub habitats at elevations below 250 meters. Flowering from February to May, this plant produces small, inconspicuous flowers in compact clusters with staminate and pistillate heads. Growing as a rounded, much-branched shrub less than 3.5 meters tall with slender, tough stems covered in soft tomentose hair. Its leaves are small, about 1 to 3 centimeters long, roughly ovate and varying from entire to palmately 3-lobed, with dense white tomentose undersides and a greener, sparsely hairy upper surface. The fruit is a distinctive bur 5 to 7 millimeters wide, covered in dense woolly material and adorned with 12 to 25 spiraled, slender spines that are generally hooked.
Identification and appearance
Key characters: 11 sympatric species; woolly burs and small rounded leaves are diagnostic
Habitat and range
Habitat: Coastal scrub
Elevation: < 250 m
Outside California: Baja California
Bloom period
Ambrosia chenopodiifolia blooms Feb-May.
Conservation status
CNPS 2B.1
How to tell it apart
vs Artemisia: Ambrosia produces spiny burs as fruits; Artemisia has tiny dry fruits without spines and strongly aromatic foliage.; vs Atriplex: Ambrosia has flower heads in spikes producing spiny burs; Atriplex has inconspicuous flowers with papery bracts and scurfy gray foliage.; vs Baccharis: Ambrosia has both male and female flowers on the same plant; Baccharis has male and female flowers on separate plants.; vs Eriogonum: Ambrosia has greenish flower heads producing spiny burs; Eriogonum has showy clusters of white, pink, or yellow flowers with papery bracts.; vs Salvia: Ambrosia has inconspicuous greenish flowers in the Asteraceae; Salvia has showy tubular lipped flowers typical of mints.
Frequently asked questions
Is Ambrosia chenopodiifolia native to California?
Yes. Ambrosia chenopodiifolia is native to California (recorded as native).
When does Ambrosia chenopodiifolia bloom?
Ambrosia chenopodiifolia blooms Feb-May.
What plant family does Ambrosia chenopodiifolia belong to?
Ambrosia chenopodiifolia is in the Asteraceae family, genus Ambrosia.
Is Ambrosia chenopodiifolia rare or endangered?
Ambrosia chenopodiifolia carries California Rare Plant Rank 2B.1, state rank S1.
What habitat does Ambrosia chenopodiifolia grow in?
Ambrosia chenopodiifolia grows in Coastal scrub.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CNPS Rare Plant Inventory · Index of California Plant Names · CalPhotos · CDFW CNDDB
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.