| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| ERCA30 | Erigeron carringtoniae Welsh | Erigeron untermannii | Asteraceae
|
| ERCA5 | Erigeron cascadensis Heller | Cascade fleabane | Asteraceae
|
| ERCA24 | Erigeron cavernensis Welsh & Atwood | Erigeron uncialis ssp. uncialis | Asteraceae
|
| ERCE | Erigeron cervinus Greene | Siskiyou fleabane | Asteraceae
|
| ERCH14 | Erigeron chinensis Jacq. | Conyza apurensis | Asteraceae
|
| ERCHA6 | Erigeron chrysopsidis Gray var. austiniae (Greene) Cronq. | Erigeron austiniae | Asteraceae
|
| ERCHB | Erigeron chrysopsidis Gray var. brevifolius Piper | Erigeron chrysopsidis | Asteraceae
|
| ERCH4 | Erigeron chrysopsidis Gray | dwarf yellow fleabane | Asteraceae
|
| ERCL | Erigeron clokeyi Cronq. | Clokey's fleabane | Asteraceae
|
| ERCO28 | Erigeron colomexicanus A. Nels. | running fleabane | Asteraceae
|
| ERCOC | Erigeron compactus Blake var. consimilis (Cronq.) Blake | Erigeron consimilis | Asteraceae
|
| ERCO3 | Erigeron compactus Blake | fernleaf fleabane | Asteraceae
|
| ERCOD | Erigeron compositus Pursh var. discoideus Gray | Erigeron compositus | Asteraceae
|
| ERCOG | Erigeron compositus Pursh var. glabratus Macoun | Erigeron compositus | Asteraceae
|
| ERCOM2 | Erigeron compositus Pursh var. multifidus (Rydb.) J.F. Macbr. & Payson | Erigeron compositus | Asteraceae
|
| ERCOP | Erigeron compositus Pursh var. pinnatisectus Gray | Erigeron pinnatisectus | Asteraceae
|
| ERCOT2 | Erigeron compositus Pursh var. typicus Hook. | Erigeron compositus | Asteraceae
|
| ERCO4 | Erigeron compositus Pursh | cutleaf daisy | Asteraceae
|
| ERCOA3 | Erigeron concinnus (Hook. & Arn.) Torr. & Gray var. aphanactis Gray | Erigeron aphanactis var. aphanactis | Asteraceae
|
| ERCOC3 | Erigeron concinnus (Hook. & Arn.) Torr. & Gray var. concinnus | Navajo fleabane | Asteraceae
|
| ERCOC4 | Erigeron concinnus (Hook. & Arn.) Torr. & Gray var. condensatus D.C. Eat. | Navajo fleabane | Asteraceae
|
| ERCOS | Erigeron concinnus (Hook. & Arn.) Torr. & Gray var. subglaber (Cronq.) Nesom | Navajo fleabane | Asteraceae
|
| ERCO27 | Erigeron concinnus (Hook. & Arn.) Torr. & Gray | Navajo fleabane | Asteraceae
|
| ERCO34 | Erigeron condensatus (D.C. Eat.) Greene | Erigeron concinnus var. condensatus | Asteraceae
|
| ERCO15 | Erigeron consimilis Cronq. | foothill fleabane | Asteraceae
|
| ERCO33 | Erigeron conspicuus Rydb. | Erigeron subtrinervis var. conspicuus | Asteraceae
|
| ERCO32 | Erigeron controversus Greene | Erigeron garrettii | Asteraceae
|
| ERCO5 | Erigeron corymbosus Nutt. | longleaf fleabane | Asteraceae
|
| ERCO6 | Erigeron coulteri Porter | large mountain fleabane | Asteraceae
|
| ERCR | Erigeron cronquistii Maguire | Cronquist's fleabane | Asteraceae
|
| ERCU6 | Erigeron cuneifolius DC. | wedgeleaf fleabane | Asteraceae
|
| ERDE12 | Erigeron debilis (Gray) Rydb. | Erigeron acris ssp. debilis | Asteraceae
|
| ERDER | Erigeron decumbens Nutt. ssp. robustior Cronq. | Erigeron decumbens var. robustior | Asteraceae
|
| ERDED | Erigeron decumbens Nutt. var. decumbens | Willamette fleabane | Asteraceae
|
| ERDER2 | Erigeron decumbens Nutt. var. robustior (Cronq.) Cronq. | Willamette fleabane | Asteraceae
|
| ERDE3 | Erigeron decumbens Nutt. | Willamette fleabane | Asteraceae
|
| ERDE4 | Erigeron delicatus Cronq. | Erigeron cervinus | Asteraceae
|
| ERDEN2 | Erigeron delphiniifolius Willd. ssp. neomexicanus (Gray) Cronq. | Erigeron neomexicanus | Asteraceae
|
| ERDEE3 | Erigeron delphiniifolius Willd. var. euneomexicanus Cronq. | Erigeron neomexicanus | Asteraceae
|
| ERDEO | Erigeron delphiniifolius Willd. var. oreophilus (Greenm.) Cronq. | Erigeron oreophilus | Asteraceae
|
| ERDI3 | Erigeron disparipilus Cronq. | white cushion fleabane | Asteraceae
|
| ERDI12 | Erigeron divaricatus Michx. | Conyza ramosissima | Asteraceae
|
| ERDIC | Erigeron divergens Torr. & Gray var. cinereus Gray | Erigeron colomexicanus | Asteraceae
|
| ERDIT | Erigeron divergens Torr. & Gray var. typicus Cronq. | Erigeron divergens | Asteraceae
|
| ERDI4 | Erigeron divergens Torr. & Gray | spreading fleabane | Asteraceae
|
| ERDR | Erigeron droebachianus O.F. Muell. ex Retz. | Erigeron acris ssp. politus | Asteraceae
|
| EREAP | Erigeron eatonii Gray ssp. plantagineus (Greene) Cronq. | Erigeron eatonii var. plantagineus | Asteraceae
|
| EREAT | Erigeron eatonii Gray ssp. typicus Cronq. | Erigeron eatonii var. eatonii | Asteraceae
|
| EREAV | Erigeron eatonii Gray ssp. villosus Cronq. | Erigeron eatonii var. villosus | Asteraceae
|
| EREAE | Erigeron eatonii Gray var. eatonii | Eaton's fleabane | Asteraceae
|
| EREAL | Erigeron eatonii Gray var. lavandulus Strother & Ferlatte | Eaton's fleabane | Asteraceae
|
| EREAN | Erigeron eatonii Gray var. nevadincola (S.F. Blake) Nesom | Eaton's fleabane | Asteraceae
|
| EREAP2 | Erigeron eatonii Gray var. plantagineus (Greene) Cronq. | Eaton's fleabane | Asteraceae
|
| EREAS | Erigeron eatonii Gray var. sonnei (Greene) Nesom | Eaton's fleabane | Asteraceae
|
| EREAV2 | Erigeron eatonii Gray var. villosus (Cronq.) Cronq. | Eaton's fleabane | Asteraceae
|
| EREA | Erigeron eatonii Gray | Eaton's fleabane | Asteraceae
|
| EREL9 | Erigeron elatior (Gray) Greene | tall fleabane | Asteraceae
|
| ERELO | Erigeron elatus (Hook.) Greene var. oligocephalus (Fern. & Wieg.) Fern. | Erigeron elatus | Asteraceae
|
| EREL10 | Erigeron elatus (Hook.) Greene | swamp boreal-daisy | Asteraceae
|
| EREL4 | Erigeron elegantulus Greene | blue dwarf fleabane | Asteraceae
|
| EREL15 | Erigeron elmeri (Greene) Greene | Elmer's erigeron | Asteraceae
|
| EREL14 | Erigeron elongatus Ledeb. | Erigeron acris ssp. politus | Asteraceae
|
| EREND2 | Erigeron engelmannii A. Nels. ssp. davisii Cronq. | Erigeron engelmannii var. davisii | Asteraceae
|
| ERENT | Erigeron engelmannii A. Nels. ssp. typicus Cronq. | Erigeron engelmannii var. engelmannii | Asteraceae
|
| EREND | Erigeron engelmannii A. Nels. var. davisii (Cronq.) Cronq. | Davis' fleabane | Asteraceae
|
| ERENE | Erigeron engelmannii A. Nels. var. engelmannii | Engelmann's fleabane | Asteraceae
|
| EREN | Erigeron engelmannii A. Nels. | Engelmann's fleabane | Asteraceae
|
| ERER8 | Erigeron eriocephalus J. Vahl | Erigeron uniflorus ssp. eriocephalus | Asteraceae
|
| ERER7 | Erigeron eriophyllus Gray | Laennecia eriophylla | Asteraceae
|
| EREV | Erigeron evermannii Rydb. | Evermann's fleabane | Asteraceae
|
| EREX4 | Erigeron eximius Greene | sprucefir fleabane | Asteraceae
|
| ERFIF | Erigeron filifolius (Hook.) Nutt. var. filifolius | threadleaf fleabane | Asteraceae
|
| ERFIR | Erigeron filifolius (Hook.) Nutt. var. robustior M.E. Peck | threadleaf fleabane | Asteraceae
|
| ERFIT | Erigeron filifolius (Hook.) Nutt. var. typicus Cronq. | Erigeron filifolius var. filifolius | Asteraceae
|
| ERFI2 | Erigeron filifolius (Hook.) Nutt. | threadleaf fleabane | Asteraceae
|
| ERFL8 | Erigeron flabellifolius Rydb. | fanleaf fleabane | Asteraceae
|
| ERFLT2 | Erigeron flagellaris Gray var. trilobatus Maguire ex Cronq. | Erigeron proselyticus | Asteraceae
|
| ERFLT | Erigeron flagellaris Gray var. typicus Cronq. | Erigeron flagellaris | Asteraceae
|
| ERFL | Erigeron flagellaris Gray | trailing fleabane | Asteraceae
|
| ERFL2 | Erigeron flettii G.N. Jones | Flett's fleabane | Asteraceae
|
| ERFL3 | Erigeron flexuosus Cronq. | Erigeron lassenianus var. lassenianus | Asteraceae
|
| ERFL15 | Erigeron floribundus (Kunth) Schultz-Bip. | Conyza floribunda | Asteraceae
|
| ERFOB | Erigeron foliosus Nutt. var. blochmaniae (Greene) Hall | Erigeron blochmaniae | Asteraceae
|
| ERFOC | Erigeron foliosus Nutt. var. confinis (T.J. Howell) Jepson | leafy fleabane | Asteraceae
|
| ERFOC2 | Erigeron foliosus Nutt. var. covillei (Greene) Compton | Erigeron breweri var. covillei | Asteraceae
|
| ERFOF | Erigeron foliosus Nutt. var. foliosus | leafy fleabane | Asteraceae
|
| ERFOF3 | Erigeron foliosus Nutt. var. franciscensis Nesom | Franciscan erigeron | Asteraceae
|
| ERFOH | Erigeron foliosus Nutt. var. hartwegii (Greene) Jepson | Hartweg's fleabane | Asteraceae
|
| ERFOM | Erigeron foliosus Nutt. var. mendocinus (Greene) Nesom | Mendocino erigeron | Asteraceae
|
| ERFOS | Erigeron foliosus Nutt. var. stenophyllus (Nutt.) Gray | Erigeron foliosus var. foliosus | Asteraceae
|
| ERFO2 | Erigeron foliosus Nutt. | leafy fleabane | Asteraceae
|
| ERFOF2 | Erigeron formosissimus Greene var. formosissimus | beautiful fleabane | Asteraceae
|
| ERFOT | Erigeron formosissimus Greene var. typicus Cronq. | Erigeron formosissimus var. formosissimus | Asteraceae
|
| ERFOV | Erigeron formosissimus Greene var. viscidus (Rydb.) Cronq. | beautiful fleabane | Asteraceae
|
| ERFO3 | Erigeron formosissimus Greene | beautiful fleabane | Asteraceae
|
| ERGA3 | Erigeron garrettii A. Nels. | Garrett's fleabane | Asteraceae
|
| ERGEC | Erigeron geiseri Shinners var. calcicola Shinners | Erigeron versicolor | Asteraceae
|
| ERGE | Erigeron geiseri Shinners | Geiser's fleabane | Asteraceae
|
| ERGI4 | Erigeron gilensis Woot. & Standl. | Erigeron versicolor | Asteraceae
|
| ERGLP3 | Erigeron glabellus Nutt. ssp. pubescens (Hook.) Cronq. | Erigeron glabellus var. pubescens | Asteraceae
|
| ERGLT | Erigeron glabellus Nutt. ssp. typicus Cronq. | Erigeron glabellus var. glabellus | Asteraceae
|