Epilobium torreyi
Narrow boisduvalia
(c) Kieran Hanrahan, some rights reserved (CC BY) · licence
Family: Onagraceae · Type: Herb · Native
Epilobium torreyi (Narrow boisduvalia) is a native California herb in the Onagraceae family, recognized by cleistogamous flowers and seeds without hair-tuft help distinguish from many congeners.
Narrow boisduvalia is a California native annual found in northwestern California (excluding North Coast), Cascade Range, Sierra Nevada, Central Valley, San Francisco Bay Area, southern Coastal Range, Modoc Plateau, and southwestern Mojave Desert in seasonally moist streambanks, seeps, and roadside ditches at elevations of 50 to 2,600 meters. Flowering from May to August, this plant produces pink or white flowers in small, delicate clusters with petals 1 to 3.2 millimeters long. Growing 15 to 65 centimeters tall with a taproot and gray spreading hairs that peel near the base, it has an upright and somewhat wispy form. Its leaves are opposite only near the base, lance-linear, 5 to 45 millimeters long, and covered in fine hairs. The fruit is a slender, cylindric capsule 8 to 14 millimeters long that is flexible and dehiscent to the base.
Identification and appearance
Key characters: 31 sympatric species; cleistogamous flowers and seeds without hair-tuft help distinguish from many congeners
Habitat and range
Habitat: Seasonally moist streambanks, seeps, roadside ditches
Elevation: 50-2600 m
California counties: Butte, Shasta, San Bernardino, Tehama, Nevada, Monterey, Lake, Kern, Madera, Santa Cruz, El Dorado, Modoc, Fresno, Plumas, Yuba, Tuolumne, Sacramento, Amador, Santa Clara, Sonoma, Calaveras, Placer, Sutter, Merced, Colusa, Glenn, Lassen, Solano, Napa, Mariposa, Humboldt, Tulare, Contra Costa, Mendocino, Stanislaus, San Joaquin, Trinity, San Mateo, San Luis Obispo, Ventura, Santa Barbara, Sierra
Outside California: to British Columbia, Idaho, northern Nevada
Bloom period
Epilobium torreyi blooms May-Aug.
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 torreyi native to California?
Yes. Epilobium torreyi is native to California (recorded as native).
When does Epilobium torreyi bloom?
Epilobium torreyi blooms May-Aug.
Where in California does Epilobium torreyi grow?
Epilobium torreyi occurs in Butte, Shasta, San Bernardino, Tehama, Nevada, Monterey, Lake, Kern and other counties, at elevations of 50-2600 m.
What plant family does Epilobium torreyi belong to?
Epilobium torreyi is in the Onagraceae family, genus Epilobium.
What habitat does Epilobium torreyi grow in?
Epilobium torreyi grows in Seasonally moist streambanks, seeps, roadside ditches.
Related species
Other California species in the same genus, family, or bioregion.
- Epilobium anagallidifolium — Alpine willowherb
- Epilobium brachycarpum — Annual fireweed
- Epilobium campestre — Smooth boisduvalia
- Epilobium canum — California fuchsia
- Epilobium canum subsp. canum
- Epilobium canum subsp. garrettii
- Eremothera boothii — Booth's sun cup
- Eremothera boothii subsp. alyssoides — Pine creek evening-primrose
- Eremothera boothii subsp. boothii — Booth's evening-primrose
- Eremothera boothii subsp. condensata
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.