Ambrosia dumosa
White bur-sage, White Bur-Sage
Photo by Chez Brungraber
Family: Asteraceae · Type: Shrub · Native
Ambrosia dumosa (White bur-sage) is a native California shrub in the Asteraceae family, recognized by silvery appearance and flattened straight spines.
White bur-sage is a California native shrub found in southern Sierra Nevada, western and Inyo Mountains, and desert regions in creosote-bush scrub at elevations from 80 to 1,700 meters. Flowering from December to June, this plant produces small heads of inconspicuous white flowers in spike-like clusters. Growing as a rounded, much-branched shrub 20 to 90 centimeters tall with stiff stems softly covered in short, fine hairs, it forms a dense, compact shape. Its leaves are sessile or with short petioles, approximately ovate, 0.5 to 4 centimeters long and divided into 1 to 3 pinnate lobes. The distinctive fruit is a bur 4 to 9 millimeters wide, golden to purple-brown with 12 to 35 sharp, spiraled spines that help in seed dispersal.
Identification and appearance
Key characters: 9 sympatric species; silvery appearance and flattened straight spines
Habitat and range
Habitat: Creosote-bush scrub
Elevation: -80-1700 m
Outside California: to southwestern Utah, Arizona, northwestern Mexico
Bloom period
Ambrosia dumosa blooms Dec-Jun.
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 dumosa native to California?
Yes. Ambrosia dumosa is native to California (recorded as native).
When does Ambrosia dumosa bloom?
Ambrosia dumosa blooms Dec-Jun.
What plant family does Ambrosia dumosa belong to?
Ambrosia dumosa is in the Asteraceae family, genus Ambrosia.
What habitat does Ambrosia dumosa grow in?
Ambrosia dumosa grows in Creosote-bush scrub.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.