Sidotheca caryophylloides
Chickweed oxytheca
(c) Adam J. Searcy, some rights reserved (CC BY) · licence
Family: Polygonaceae · Type: Herb · Native
Conservation status: CNPS 4.3
Sidotheca caryophylloides (Chickweed oxytheca) is a native California herb in the Polygonaceae family, recognized by smaller flowers and compact habit.
Chickweed oxytheca is a California native annual found in southern Sierra Nevada, Transverse Ranges, and San Jacinto Mountains in sandy or gravelly habitats at elevations of 1,300 to 2,600 meters. Flowering from June to September, this plant produces green-yellow to reddish flowers with three-lobed perianth segments. Growing with delicate stems 10 to 25 centimeters tall and spreading 3 to 40 centimeters in diameter, it forms a low, intricate ground-hugging pattern. Its leaves are relatively narrow, measuring 1 to 6 centimeters long and 0.3 to 1.2 centimeters wide, with distinctive involucre bracts featuring short green to reddish awns. The fruit is small, measuring 1.2 to 1.5 millimeters in length.
Identification and appearance
Key characters: 2 sympatric species; distinguished by smaller flowers and compact habit
Habitat and range
Habitat: Sand or gravel
Elevation: 1300-2600 m
California counties: Los Angeles, San Bernardino, Ventura, Riverside, Tulare
Bloom period
Sidotheca caryophylloides blooms Jun-Sep.
Conservation status
CNPS 4.3
How to tell it apart
vs Chorizanthe: Sidotheca has 5-6 awns per involucre and fringed petals; Chorizanthe typically has different awn counts and patterns.; vs Oxytheca: Sidotheca has fringed or 3-lobed petals; Oxytheca has smooth-edged, entire petals.; vs Acanthoscyphus: Sidotheca has 5-6 awns and fringed petals; Acanthoscyphus has 7-30+ awns and entire petals.
Frequently asked questions
Is Sidotheca caryophylloides native to California?
Yes. Sidotheca caryophylloides is native to California (recorded as native).
When does Sidotheca caryophylloides bloom?
Sidotheca caryophylloides blooms Jun-Sep.
Where in California does Sidotheca caryophylloides grow?
Sidotheca caryophylloides occurs in Los Angeles, San Bernardino, Ventura, Riverside, Tulare, at elevations of 1300-2600 m.
What plant family does Sidotheca caryophylloides belong to?
Sidotheca caryophylloides is in the Polygonaceae family, genus Sidotheca.
Is Sidotheca caryophylloides rare or endangered?
Sidotheca caryophylloides carries California Rare Plant Rank 4.3, state rank S4.
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.