willowherbs

genus Epilobium

Member of evening primrose family (family Onagraceae)
dicots (class Magnoliopsida)
flowering plants (subphylum Angiospermae)

There are no other wild species of this genus in the bay area.

Key features:

overall plant height
leaves opposite above mid stem vs. alternate or clustered
stem peeling near base or not
leaf veins conspicuous or obscure

leaves generally opposite up to inflorescence
proximal stem not peeling

california fuchsia
Epilobium canum

common

See also red larkspur (Delphinium nudicaule), which has a spur behind the stem and much shorter filaments.

fringed willowherb
Epilobium ciliatum

leaf veins conspicuous
common

hall’s willowherb
Epilobium hallianum

leaf veins ± obscure
common

leaves opposite only near base, alternate or clustered distally
proximal stem generally peeling

These are generally distinguished in Jepson by seed characteristics. I’ve sorted them by maximum height (which roughly corresponds to maximum petal length). Good luck!

panicled willowherb
Epilobium brachycarpum

20–200 cm tall
leaf 10–55 mm, linear to narrowly elliptic, generally folded along midrib, ± glabrous; petiole 0–4 mm
panicle or raceme inflorescence
hypanthium 1.5–8(16) mm
petals 2–15(20) mm, white to rose-purple
common
see also the 5-petaled stiff velezia (Velezia rigida)

denseflower willowherb
Epilobium densiflorum

5–150 cm tall, simple or branched distally
leaf 14–85 mm, lanceolate to sublinear, ± sessile; distal leaves hairy
inflorescence leafy, ± dense spike
hypanthium 1.3–4 mm
petals 3–10 mm, rose-purple to white
common

torrey’s willowherb
Epilobium torreyi

4–65 cm tall
leaf 5–45 mm, ± lance-linear, hairy, ± sessile
bracts leaf-like
hypanthium 0.4–1 mm
petals 1–3.2 mm, pink or white
Jasper Ridge, Nisene Marks, Sunol, Mt. Diablo, Mt. Tam

pygmy willowherb
Epilobium campestre

10–55 cm tall
leaf 8–35 mm, lanceolate, generally hairy, ± sessile
inflorescence crowded
hypanthium 0.3–1.1 mm
petals 1–3.2 mm, pink
Los Trancos, Don Edwards, Sunol, Pleasanton Ridge, Mt. Diablo, Briones

california willowherb
Epilobium ravenii

< 45 cm tall
leaf 5–30 mm, sublinear to lanceolate, generally folded along midrib, distal clustered; petiole 1–12 mm
inflorescence crowded
hypanthium 0.4–0.8 mm
petals 1.8–3 mm, white
Mt. Tam

little willowherb
Epilobium minutum

< 40 cm tall
leaf 9–25 mm, generally lanceolate to narrowly elliptic, ± glabrous; petiole 0–2 mm
inflorescence open
hypanthium 1.1–1.5 mm
petals 2–5 mm, white or pink
scattered

selfing willowherb
Epilobium cleistogamum

15–32 cm tall
leaf 15–55 mm, linear to narrowly elliptic; distal leaves hairy, often folded along midrib
infloescence leafy, spreading and glandular hairy
hypanthium 0.5–1 mm
petals 2–5.5 mm, white to pale pink
very rare: Henry Coe

4 observed taxons / 6 unobserved taxons / 1 key

Chris’s observations: 64 (41 are research grade)

Locations:

Pinnacles NP: 5
Monte Bello OSP: 4
Murray Ranch SP: 4
Russian Ridge OSP: 4
Alum Rock Park, San Jose: 3
Huckleberry Botanic RP: 3
Wunderlich CP: 3
Bear Creek Redwoods OSP: 2
Coal Creek OSP: 2
Portola Redwoods SP: 2
Sam McDonald CP: 2
Sierra Azul OSP: 2
Sierra Vista OSP: 2
Almaden Quicksilver CP
Ansel Adams Wilderness
Big Basin SP
Coyote Lake / Harvey Bear Ranch CP
Don Edwards National Wildlife Refuge
Ed R. Levin CP
Edgewood Park & Natural Preserve
El Corte de Madera OSP
Golden Gate National Recreation Area
Henry Coe SP
Hood Mountain RP, Sonoma County
Joseph D. Grant CP
La Honda Creek OSP
Mt. Diablo SP
Nisene Marks SP
Pescadero Creek CP
Purisima Creek Redwoods OSP
Rancho Cañada del Oro OSP
San Bruno Mountain State & County Park
Sibley Volcanic RP
Skyline Ridge OSP
Stevens Creek CP
Sweeney Ridge National Recreation Area
Ulistac Natural Area, Santa Clara
Wilder Ranch SP
Yosemite NP

Months:

Jun.: 3
Jul.: 13
Aug.: 13
Sep.: 10
Oct.: 14
Nov.: 11

For more details, use advanced search.

Taxon info: iNaturalist – Calflora – Jepson eFlora – FNA

Bay Area species: iNaturalist – Calflora

willowherbs

leaves generally opposite up to inflorescence proximal stem not peeling

leaves opposite only near base, alternate or clustered distally proximal stem generally peeling

leaves generally opposite up to inflorescence
proximal stem not peeling

leaves opposite only near base, alternate or clustered distally
proximal stem generally peeling