Lomatium triternatum var. triternatum
Lewis' lomatium
Photo: parent species Lomatium triternatum · (c) Kieran Hanrahan, some rights reserved (CC BY) · licence
Family: Apiaceae · Type: Herb · Native
Lomatium triternatum var. triternatum (Lewis' lomatium) is a native California herb in the Apiaceae family, recognized by . Key features: prominent stem, large leaflets, hairless fruits vs. var. macrocarpum.
Lewis' lomatium is a California native perennial found in the Klamath Ranges, northern California Coast Ranges, and Warner Mountains in open serpentine ridges, scrub, and pine forest at elevations of 200 to 2,000 meters. Flowering from April to July, this plant produces delicate white to pale yellow flowers in compound umbels characteristic of the Apiaceae family. Growing with slender stems 10 to 40 centimeters tall, it has a distinctive finely dissected foliage pattern. Its leaves are finely divided into numerous small, thin leaflets, creating a lacy, intricate appearance typical of the Lomatium genus. The glabrous ovary and multiple chromosome configurations (2n=22,44) reflect its genetic complexity and adaptability to serpentine landscapes.
Identification and appearance
Key characters: 33 sympatric species. Key features: prominent stem, large leaflets, hairless fruits vs. var. macrocarpum
Habitat and range
Habitat: Open serpentine ridges, scrub, pine forest
Elevation: 200-2000 m
California counties: Lassen, Modoc, Trinity, Shasta, Del Norte, Siskiyou, Humboldt, Sierra
Outside California: to Washington, western Canada, Montana, western Nevada
Bloom period
Lomatium triternatum var. triternatum blooms Apr-Jul.
How to tell it apart
vs Tauschia: Lomatium fruits have prominent marginal wings; Tauschia fruits lack wings or have only slight ribs.; vs Sanicula: Lomatium has typical umbrella-shaped flower clusters; Sanicula has dense ball-like flower heads with hooked bristles.; vs Cymopterus: Lomatium grows upright with a stem; Cymopterus is stemless and grows flat to the ground.; vs Conium: Lomatium grows in dry natural habitats; Conium has purple-spotted stems and grows in moist disturbed areas.; vs Daucus: Lomatium fruits are flat with thin wings; Daucus fruits are cylindrical with spiny bristles.
Frequently asked questions
Is Lomatium triternatum var. triternatum native to California?
Yes. Lomatium triternatum var. triternatum is native to California (recorded as native).
When does Lomatium triternatum var. triternatum bloom?
Lomatium triternatum var. triternatum blooms Apr-Jul.
Where in California does Lomatium triternatum var. triternatum grow?
Lomatium triternatum var. triternatum occurs in Lassen, Modoc, Trinity, Shasta, Del Norte, Siskiyou, Humboldt, Sierra, at elevations of 200-2000 m.
What plant family does Lomatium triternatum var. triternatum belong to?
Lomatium triternatum var. triternatum is in the Apiaceae family, genus Lomatium.
What habitat does Lomatium triternatum var. triternatum grow in?
Lomatium triternatum var. triternatum grows in Open serpentine ridges, scrub, pine forest.
Related species
Other California species in the same genus, family, or bioregion.
- Lomatium utriculatum — Bladder parsnip
- Lomatium vaginatum — Broadsheath desertparsley
- Lomatium austiniae — Plummer's lomatium
- Lomatium bicolor var. leptocarpum — Slender fruited lomatium
- Lomatium californicum — California lomatium
- Lomatium canbyi — Canby's lomatium
- Oenanthe sarmentosa — Pacific oenanthe
- Oenanthe sp.
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.