Tiarella trifoliata var. trifoliata
Threeleaf foamflower
Photo: parent species Tiarella trifoliata · (c) Gavin Slater, some rights reserved (CC BY) · licence
Family: Saxifragaceae · Type: Herb · Native
Conservation status: CNPS 3.2
Tiarella trifoliata var. trifoliata (Threeleaf foamflower) is a native California herb in the Saxifragaceae family.
Threeleaf foamflower is a California native perennial found in the Klamath Ranges and northern Coast Ranges of Humboldt County in moist shady streambanks at elevations below 1,500 meters. Flowering from June to August, this plant produces delicate white flowers in small clusters. Growing with slender stems 15 to 40 centimeters tall, it forms clumps with distinctive compound leaves. Its leaves are broadly divided into three leaflets, each 3 to 9 centimeters wide, with sharply toothed edges and a delicate, lacy appearance. The plant creates soft, foam-like clusters of white flowers that give it its charming common name.
Identification and appearance
Key characters: 1 sympatric species; key differentiators are leaf size, division pattern, and tooth shape
Habitat and range
Habitat: Moist shady streambanks
Elevation: < 1500 m
California counties: Mendocino
Outside California: to Alaska, eastern British Columbia, Montana
Bloom period
Tiarella trifoliata var. trifoliata blooms Jun-Aug.
Conservation status
CNPS 3.2
How to tell it apart
vs Heuchera: Tiarella has white petals and a loose panicle; Heuchera has tiny greenish-pink petals and bell-shaped flowers.; vs Tellima: Tiarella petals are entire (smooth-edged); Tellima petals are deeply fringed into 5-7 narrow segments.; vs Vancouveria: Tiarella has simple flowers in clusters; Vancouveria has compound leaves with leaflets and nodding columbine-like flowers.; vs Boykinia: Tiarella has unequal fruit valves; Boykinia has equal fruit valves and saucer-shaped flowers.; vs Rubus: Tiarella has tiny white flowers in spikes; Rubus has larger rose-like flowers and compound leaves.
Frequently asked questions
Is Tiarella trifoliata var. trifoliata native to California?
Yes. Tiarella trifoliata var. trifoliata is native to California (recorded as native).
When does Tiarella trifoliata var. trifoliata bloom?
Tiarella trifoliata var. trifoliata blooms Jun-Aug.
Where in California does Tiarella trifoliata var. trifoliata grow?
Tiarella trifoliata var. trifoliata occurs in Mendocino, at elevations of < 1500 m.
What plant family does Tiarella trifoliata var. trifoliata belong to?
Tiarella trifoliata var. trifoliata is in the Saxifragaceae family, genus Tiarella.
Is Tiarella trifoliata var. trifoliata rare or endangered?
Tiarella trifoliata var. trifoliata carries California Rare Plant Rank 3.2, state rank S2S3.
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.