Fireweed, Great Willow-herb: Chamaenerion angustifolium ssp. circumvagum (Synonyms: Chamaenerion angustifolium, Chamaenerion angustifolium var. canescens, Chamerion angustifolium ssp. angustifolium, Chamerion angustifolium ssp. circumvagum, Chamerion angustifolium var. angustifolium, Chamerion angustifolium var. canescens, Chamerion danielsii, Chamerion platyphyllum, Chamerion spicatum, Epilobium angustifolium, Epilobium angustifolium ssp. circumvagum, Epilobium angustifolium ssp. macrophyllum, Epilobium angustifolium var. abbreviatum, Epilobium angustifolium var. canescens, Epilobium angustifolium var. intermedium, Epilobium angustifolium var. macrophyllum, Epilobium angustifolium var. platyphyllum, Epilobium spicatum) -
Broadleaf Willowherb, Broad-leaf Willowherb, Dwarf Fireweed, River Beauty: Chamaenerion latifolium (Synonyms: Chamerion latifolium, Epilobium latifolium) -
Alpine Willowherb, Pimpernel Willowherb: Epilobium anagallidifolium (Synonyms: Epilobium alpinum, Epilobium alpinum var. alpinum) -
Autumn Willowherb, Tall Annual Willowherb: Epilobium brachycarpum (Synonyms: Epilobium jucundum, Epilobium paniculatum , Epilobium paniculatum var. hammondii, Epilobium paniculatum var. jucundum, Epilobium paniculatum var. laevicaule, Epilobium paniculatum var. paniculatum, Epilobium paniculatum var. subulatum, Epilobium paniculatum var. tracyi) - Annual.
Smooth Spikeprimrose, Smooth Spike-primrose, Smooth Willowherb: Epilobium campestre (Synonyms: Boisduvalia glabella, Epilobium pygmaeum) - Annual.
Ciliate Willowherb, Purple-leaved Willowherb: Epilobium ciliatum ssp. ciliatum (Synonyms: Epilobium adenocaulon var. adenocaulon, Epilobium adenocaulon var. perplexans, Epilobium brevistylum, Epilobium brevistylum var. brevistylum, Epilobium brevistylum var. ursinum, Epilobium californicum, Epilobium ciliatum var. ciliatum, Epilobium glandulosum, Epilobium glandulosum var. macounii, Epilobium occidentale, Epilobium watsonii var. occidentale, Epilobium watsonii var. parishii) -
Bog Willowherb, Ciliate Willowherb, Common Willowherb, Fringed Willowherb: Epilobium ciliatum ssp. glandulosum (Synonyms: Epilobium adenocaulon var. cinerascens, Epilobium adenocaulon var. occidentale, Epilobium boreale, Epilobium brevistylum var. brevistylum, Epilobium ciliatum var. glandulosum, Epilobium glandulosum, Epilobium glandulosum var. cardiophyllum, Epilobium glandulosum var. glandulosum, Epilobium glandulosum var. occidentale, Epilobium watsonii var. occidentale) -
Fringed Willowherb, Pacific Willowherb, Watson's Willowherb, Watson's Willow-herb: Epilobium ciliatum ssp. watsonii (Synonyms: Epilobium franciscanum, Epilobium watsonii, Epilobium watsonii var. franciscanum, Epilobium watsonii var. watsonii) -
Club-fruited Willowherb, Club-pod Willow-herb, Talus Willowherb: Epilobium clavatum (Synonyms: Epilobium alpinum, Epilobium alpinum var. albiflorum, Epilobium alpinum var. clavatum, Epilobium clavatum var. glareosum, Epilobium glareosum) -
Denseflower Spikeprimrose, Dense-flower Willowherb, Dense Spike-primrose, Denseflower Spike Primrose: Epilobium densiflorum (Synonyms: Boisduvalia densiflora, Boisduvalia densiflora var. densiflora, Boisduvalia densiflora var. pallescens, Boisduvalia densiflora var. salina) - Annual.
California Willowherb, Suksdorf's Willowherb: Epilobium foliosum (Synonym: Epilobium minutum var. foliosum)
Glaucous Willowherb, Smooth Willowherb: Epilobium glaberrimum ssp. fastigiatum (Synonym: Epilobium glaberrimum var. fastigiatum) - Herbage usually glaucous. Plants of drier, gravelly or rocky slopes, road cuts, etc. Leaves lanceolate to ovate, 10-30 mm long, closely crowded and overlapping. Stems 10-30 cm high. Ovaries usually glabrous.
Glaucous Willowherb, Smooth Willowherb: Epilobium glaberrimum ssp. glaberrimum (Synonym: Epilobium glaberrimum var. glaberrimum) - Herbage usually glaucous. Plants of drier, gravelly or rocky slopes, road cuts, etc. Leaves lanceolate to narrowly ovate, 25-45 mm long, widely spaced or barely overlapping. Stems 25-45 cm high. Ovaries hairy.
Hall's Willowherb, Sierra Willowherb: Epilobium hallianum (Synonyms: Epilobium brevistylum, Epilobium brevistylum var. subfalcatum, Epilobium brevistylum var. tenue, Epilobium delicatum, Epilobium glandulosum, Epilobium glandulosum var. tenue, Epilobium ursinum, Epilobium halleanum, Epilobium brevistylum var. tenue, Epilobium delicatum, Epilobium pringleanum) -
Codlins and Cream, Fiddle Grass, Fiddle Grass Willowherb, Fiddlegrass: Epilobium hirsutum
Alpine Willowherb, Hornemann's Willowherb: Epilobium hornemannii ssp. hornemannii (Synonyms: Epilobium alpinum, Epilobium alpinum var. nutans, Epilobium hornemannii var. hornemannii) -
Milkflower Willowherb, Milk-flower Willowherb, White-flowered Willowherb: Epilobium lactiflorum (Synonyms: Epilobium alpinum, Epilobium alpinum var. lactiflorum, Epilobium hornemannii var. lactiflorum) -
Low Willowherb: Epilobium leptocarpum -
Chaparral Willowherb, Small-flowered Willowherb Epilobium minutum (Synonym: Epilobium minutum var. minutum) - Annual.
Rockfringe, Rose Willowherb, Rose Willow-herb: Epilobium obcordatum - Perennial. Petals over 9 mm long.
Slimstem Willowherb: Epilobium oregonense (Synonyms: Epilobium alpinum, Epilobium alpinum var. gracillimum) -
Pale Boisduvalia: Epilobium pallidum (Synonyms: Boisduvalia macrantha, Boisduvalia pallida) - Annual.
Marsh Willowherb, Swamp Willowherb: Epilobium palustre
Brook Spike-primrose, Brook Willowherb, Stiff Spikeprimrose, Stiff Spike-primrose, Torrey's Epilobium, Torrey's Willowherb: Epilobium torreyi (Synonym: Boisduvalia stricta) - Annual.