Epilobium luteum
Yellow willowherb
(c) Gabriel Campbell-Martinez, some rights reserved (CC BY) · licence
Family: Onagraceae · Type: Herb · Native
Conservation status: CNPS 2B.3
Epilobium luteum (Yellow willowherb) is a native California herb in the Onagraceae family, recognized by but yellow flower color completely diagnostic.
Yellow willowherb is a rare (CNPS 2B.3) California native perennial found in northern Klamath Ranges and northern Sierra Nevada High Sierra in moist streambanks and montane meadows at elevations of 1,200 to 2,500 meters. Flowering from July to September, this plant produces cream-yellow flowers 12 to 22 millimeters long with nodding buds densely covered in fine glandular hairs. Growing with loosely clumped stems 10 to 80 centimeters tall, it has short stolons and strigose hairs arranged in decurrent lines. Its leaves vary from spoon-shaped on lower stems to ovate or elliptic, with conspicuous veins and petioles up to 3 millimeters long. The fruit is 35 to 75 millimeters long and slightly hairy, with seed tufts that are reddish and persistent.
Identification and appearance
Key characters: 26 sympatric species but yellow flower color completely diagnostic
Habitat and range
Habitat: Moist streambanks, montane meadows
Elevation: +- 1200-2500 m.
Outside California: to Alaska, western Canada
Bloom period
Epilobium luteum blooms Jul-Sep.
Conservation status
CNPS 2B.3
How to tell it apart
vs Penstemon: Epilobium has 4 notched petals and opposite leaves; Penstemon has 5-lobed tubular flowers (snapdragon family).; vs Gambelia: Epilobium has 4 notched petals; Gambelia has 5-lobed tubular snapdragon-like flowers.; vs Fuchsia: Epilobium has notched petals spreading flat; Fuchsia has dangling tubular flowers with protruding stamens.; vs Keckiella: Epilobium has 4 notched petals; Keckiella has 5-lobed tubular snapdragon-like flowers.; vs Diplacus: Epilobium has 4 notched petals; Diplacus has 5-lobed tubular monkey flowers.
Frequently asked questions
Is Epilobium luteum native to California?
Yes. Epilobium luteum is native to California (recorded as native).
When does Epilobium luteum bloom?
Epilobium luteum blooms Jul-Sep.
What plant family does Epilobium luteum belong to?
Epilobium luteum is in the Onagraceae family, genus Epilobium.
Is Epilobium luteum rare or endangered?
Epilobium luteum carries California Rare Plant Rank 2B.3, state rank S1.
What habitat does Epilobium luteum grow in?
Epilobium luteum grows in Moist streambanks, montane meadows.
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.