Euphorbia ocellata subsp. rattanii
Stony creek spurge, Stony Creek Spurge
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Family: Euphorbiaceae · Type: Herb · Native
Conservation status: CNPS 1B.2
Euphorbia ocellata subsp. rattanii (Stony creek spurge) is a native California herb in the Euphorbiaceae family, recognized by hairy habit and white appendages.
Stony creek spurge is a rare (CNPS 1B.2) California native annual found in northern Sacramento Valley counties of Glenn and Tehama in sandy or stony ground at elevations below 100 meters. Flowering from May to September, this plant produces small white flowers with distinctive gland appendages wider than the glands themselves. Growing with hairy stems in low, spreading formations, it maintains a delicate and compact structure. Its leaves are small, less than 10 millimeters long, with distinctive ovate blades that contribute to its understated appearance. The plant's subtle characteristics make it a unique component of its sparse, rocky habitat.
Identification and appearance
Key characters: 12 sympatric species; distinguished by hairy habit and white appendages
Habitat and range
Habitat: Sandy or stony ground
Elevation: < 100 m
Bloom period
Euphorbia ocellata subsp. rattanii blooms May-Sep.
Conservation status
CNPS 1B.2
How to tell it apart
vs Croton: Euphorbia bleeds milky white latex and packs its flowers into a tiny cup (cyathium) rimmed with nectar glands; Croton has watery sap, stellate or scaly hairs, and ordinary small separate male and female flowers.; vs Stillingia: Euphorbia flowers sit in a gland-bearing cyathium; Stillingia bears its flowers in a spike with a pair of glands flanking each subtending bract and has no cyathium cup.; vs Ditaxis: Euphorbia has latex and the cyathium; Ditaxis has clear sap, 5-parted petaled male and female flowers, and 2-forked (malpighiaceous) hairs.; vs Asclepias: Both ooze milky sap, but Euphorbia's minute flowers cluster in a cyathium and ripen into a 3-lobed capsule; milkweeds have showy 5-parted flowers with a crown and paired follicles of plumed seeds.; vs Polygonum: Prostrate mat spurges leak milky sap when torn and have paired stipules with opposite leaves at the nodes; knotweeds have clear sap and a papery sheath (ocrea) wrapping each node.
Frequently asked questions
Is Euphorbia ocellata subsp. rattanii native to California?
Yes. Euphorbia ocellata subsp. rattanii is native to California (recorded as native).
When does Euphorbia ocellata subsp. rattanii bloom?
Euphorbia ocellata subsp. rattanii blooms May-Sep.
What plant family does Euphorbia ocellata subsp. rattanii belong to?
Euphorbia ocellata subsp. rattanii is in the Euphorbiaceae family, genus Euphorbia.
Is Euphorbia ocellata subsp. rattanii rare or endangered?
Euphorbia ocellata subsp. rattanii carries California Rare Plant Rank 1B.2, state rank S2?.
What habitat does Euphorbia ocellata subsp. rattanii grow in?
Euphorbia ocellata subsp. rattanii grows in Sandy or stony ground.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · 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.