Polycarpon tetraphyllum subsp. tetraphyllum
Four-leaved allseed
(c) Nicola van Berkel, some rights reserved (CC BY-SA), uploaded by Nicola van Berkel · licence
Family: Caryophyllaceae · Type: Herb
Polycarpon tetraphyllum subsp. tetraphyllum (Four-leaved allseed) is a California herb in the Caryophyllaceae family, recognized by 2 sympatric subspecies; distinguished by larger non-succulent leaves and disturbed habitat preference.
Four-leaved allseed is a naturalized annual found in disturbed shaded areas and roadsides at elevations below 450 meters. Flowering from spring to fall, this plant produces tiny white to pale greenish flowers that rarely open except in larger plants. Growing with prostrate to erect stems 1 to 6 centimeters tall, often much-branched and mounding in wetter conditions. Its leaves are broadly ovate to obovate, typically 4 to 12 millimeters long, with distinctive lanceolate stipules. The plant forms delicate, granular seeds and can adapt to create dense, low-growing mats in disturbed ground.
Identification and appearance
Key characters: 2 sympatric subspecies; distinguished by larger non-succulent leaves and disturbed habitat preference
Habitat and range
Habitat: Disturbed shaded areas, roadsides
Elevation: < 450 m, 1180 m
Outside California: British Columbia, Texas, southeastern North America, native to southern Europe
Bloom period
Polycarpon tetraphyllum subsp. tetraphyllum blooms Spring-fall.
How to tell it apart
vs Euphorbia: Polycarpon has separate tiny white flowers; Euphorbia has a cup-like cyathium with milky sap when broken.; vs Stellaria: Polycarpon has spoon-shaped leaves with stalks; Stellaria has stalkless, pointed oval leaves.; vs Portulaca: Polycarpon has thin, flat spoon-shaped leaves; Portulaca has succulent, cylindrical leaves.; vs Soleirolia: Polycarpon has white flowers with visible separate petals; Soleirolia has tiny flowers hidden in leaf axils.; vs Crassula: Polycarpon has thin, flat leaves; Crassula has thick, succulent leaves often in tight rosettes.
Frequently asked questions
When does Polycarpon tetraphyllum subsp. tetraphyllum bloom?
Polycarpon tetraphyllum subsp. tetraphyllum blooms Spring-fall.
What plant family does Polycarpon tetraphyllum subsp. tetraphyllum belong to?
Polycarpon tetraphyllum subsp. tetraphyllum is in the Caryophyllaceae family, genus Polycarpon.
What habitat does Polycarpon tetraphyllum subsp. tetraphyllum grow in?
Polycarpon tetraphyllum subsp. tetraphyllum grows in Disturbed shaded areas, roadsides.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · 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.