Ranunculus canus var. canus
Hartweg's buttercup
Photo: parent species Ranunculus canus · no rights reserved · CC0
Family: Ranunculaceae · Type: Perennial · Native
Ranunculus canus var. canus (Hartweg's buttercup) is a native California perennial in the Ranunculaceae family, recognized by fewer petals than var. ludovicianus.
Hartweg's buttercup is a California native perennial found in northern Coast Ranges, northern Sierra Nevada foothills, Great Valley, and eastern San Francisco Bay Area grasslands and open oak woodlands at elevations below 1,200 meters. Flowering from March to July, this plant produces white flowers with 5 to 7 delicate petals. Growing with slender stems reaching 10 to 30 centimeters tall, it spreads in loose, open clusters across grassy landscapes. Its leaves feature distinctive ovate to oblong-ovate segments with toothed edges, each segment acute or bluntly pointed. The plant forms small, compact clumps with finely divided foliage characteristic of the buttercup family.
Identification and appearance
Key characters: 36 sympatric species; fewer petals than var. ludovicianus
Habitat and range
Habitat: Grassland, open oak woodland
Elevation: < 1200 m
Bloom period
Ranunculus canus var. canus blooms Mar-Jul.
How to tell it apart
vs Lasthenia: Ranunculus has separate petals around a central disk; Lasthenia has many tiny ray flowers around a disk (composite head).; vs Bowlesia: Ranunculus has glossy yellow petals in conspicuous flowers; Bowlesia has tiny white flowers in umbels with divided leaves.; vs Potentilla: Ranunculus has nectaries at petal bases and many pistils; Potentilla has no nectaries and styles attached to ovary sides.; vs Papaver: Ranunculus has 5 petals and many pistils; Papaver has 4 crinkled petals and a single large stigma disk.; vs Oxalis: Ranunculus has glossy separate petals; Oxalis has clover-like leaves and tubular flowers that close at night.
Frequently asked questions
Is Ranunculus canus var. canus native to California?
Yes. Ranunculus canus var. canus is native to California (recorded as native).
When does Ranunculus canus var. canus bloom?
Ranunculus canus var. canus blooms Mar-Jul.
What plant family does Ranunculus canus var. canus belong to?
Ranunculus canus var. canus is in the Ranunculaceae family, genus Ranunculus.
What habitat does Ranunculus canus var. canus grow in?
Ranunculus canus var. canus grows in Grassland, open oak woodland.
Related species
Other California species in the same genus, family, or bioregion.
- Ranunculus canus var. ludovicianus — Hartweg's buttercup
- Ranunculus cymbalaria — Alkali buttercup
- Ranunculus eschscholtzii — Eschscholtz's buttercup
- Ranunculus eschscholtzii var. eschscholtzii — Eschscholtz's buttercup
- Ranunculus eschscholtzii var. oxynotus — Eschscholtz's buttercup
- Ranunculus eschscholtzii var. suksdorfii — Suksdorf's buttercup
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-09-30
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.