| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| ASCA8 | Astragalus callithrix Barneby | Callaway milkvetch | Fabaceae
|
| ASCAC5 | Astragalus calycosus Torr. ex S. Wats. var. calycosus | Torrey's milkvetch | Fabaceae
|
| ASCAM | Astragalus calycosus Torr. ex S. Wats. var. mancus (Rydb.) Barneby | Astragalus calycosus var. calycosus | Fabaceae
|
| ASCAM2 | Astragalus calycosus Torr. ex S. Wats. var. monophyllidius (Rydb.) Barneby | Torrey's milkvetch | Fabaceae
|
| ASCAS | Astragalus calycosus Torr. ex S. Wats. var. scaposus (Gray) M.E. Jones | Torrey's milkvetch | Fabaceae
|
| ASCA9 | Astragalus calycosus Torr. ex S. Wats. | Torrey's milkvetch | Fabaceae
|
| ASCA10 | Astragalus camptopus Barneby | Bruneau milkvetch | Fabaceae
|
| ASCAB | Astragalus canadensis L. var. brevidens (Gandog.) Barneby | shorttooth Canadian milkvetch | Fabaceae
|
| ASCAC6 | Astragalus canadensis L. var. canadensis | Canadian milkvetch | Fabaceae
|
| ASCAC7 | Astragalus canadensis L. var. carolinianus (L.) M.E. Jones | Astragalus canadensis var. canadensis | Fabaceae
|
| ASCAL | Astragalus canadensis L. var. longilobus Fassett | Astragalus canadensis var. canadensis | Fabaceae
|
| ASCAM3 | Astragalus canadensis L. var. mortonii (Nutt.) S. Wats. | Morton's Canadian milkvetch | Fabaceae
|
| ASCA11 | Astragalus canadensis L. | Canadian milkvetch | Fabaceae
|
| ASCA27 | Astragalus candelarius Sheldon | Astragalus purshii var. tinctus | Fabaceae
|
| ASCA19 | Astragalus canovirens (Rydb.) Barneby | Astragalus coltonii var. moabensis | Fabaceae
|
| ASCA12 | Astragalus caricinus (M.E. Jones) Barneby | buckwheat milkvetch | Fabaceae
|
| ASCA29 | Astragalus carolinianus L. | Astragalus canadensis var. canadensis | Fabaceae
|
| ASCA28 | Astragalus caryocarpus Ker-Gawl. | Astragalus crassicarpus var. crassicarpus | Fabaceae
|
| ASCA14 | Astragalus casei Gray ex Brewer & S. Wats. | Case's milkvetch | Fabaceae
|
| ASCAC | Astragalus castaneiformis S. Wats. var. consobrinus Barneby | Astragalus consobrinus | Fabaceae
|
| ASCAT | Astragalus castaneiformis S. Wats. var. typicus Barneby | Astragalus castaneiformis | Fabaceae
|
| ASCA15 | Astragalus castaneiformis S. Wats. | chestnut milkvetch | Fabaceae
|
| ASCA16 | Astragalus castetteri Barneby | Castetter's milkvetch | Fabaceae
|
| ASCA26 | Astragalus catalinensis Nutt. | Astragalus didymocarpus var. didymocarpus | Fabaceae
|
| ASCEA | Astragalus ceramicus Sheldon var. apus Barneby | painted milkvetch | Fabaceae
|
| ASCEC | Astragalus ceramicus Sheldon var. ceramicus | painted milkvetch | Fabaceae
|
| ASCEF | Astragalus ceramicus Sheldon var. filifolius (Gray) F.J. Herm. | painted milkvetch | Fabaceae
|
| ASCE | Astragalus ceramicus Sheldon | painted milkvetch | Fabaceae
|
| ASCE2 | Astragalus cerussatus Sheldon | powdery milkvetch | Fabaceae
|
| ASCHC2 | Astragalus chamaeleuce Gray var. chamaeleuce | cicada milkvetch | Fabaceae
|
| ASCHL2 | Astragalus chamaeleuce Gray var. laccoliticus (M.E. Jones) Barneby ex Isely | cicada milkvetch | Fabaceae
|
| ASCH4 | Astragalus chamaeleuce Gray | cicada milkvetch | Fabaceae
|
| ASCH5 | Astragalus chamaemeniscus Barneby | ground-crescent milkvetch | Fabaceae
|
| ASCH6 | Astragalus chinensis L. f. | Chinese milkvetch | Fabaceae
|
| ASCH7 | Astragalus chloodes Barneby | grass milkvetch | Fabaceae
|
| ASCH9 | Astragalus chuckwallae Abrams | Astragalus nutans | Fabaceae
|
| ASCH13 | Astragalus chuskanus Barneby & Spellenberg | San Juan milkvetch | Fabaceae
|
| ASCI2 | Astragalus cibarius Sheldon | browse milkvetch | Fabaceae
|
| ASCI4 | Astragalus cicer L. | cicer milkvetch | Fabaceae
|
| ASCIC3 | Astragalus cimae M.E. Jones var. cimae | cima milkvetch | Fabaceae
|
| ASCIS | Astragalus cimae M.E. Jones var. sufflatus Barneby | cima milkvetch | Fabaceae
|
| ASCI3 | Astragalus cimae M.E. Jones | cima milkvetch | Fabaceae
|
| ASCI7 | Astragalus cinerascens (Rydb.) Tidestrom | Astragalus tetrapterus | Fabaceae
|
| ASCL | Astragalus claranus Jepson | Napa milkvetch | Fabaceae
|
| ASCL2 | Astragalus clevelandii Greene | Cleveland's milkvetch | Fabaceae
|
| ASCOC6 | Astragalus cobrensis Gray var. cobrensis | copper mine milkvetch | Fabaceae
|
| ASCOM | Astragalus cobrensis Gray var. maguirei Kearney | Maguire's milkvetch | Fabaceae
|
| ASCO5 | Astragalus cobrensis Gray | copper mine milkvetch | Fabaceae
|
| ASCO6 | Astragalus coccineus Brandeg. | scarlet milkvetch | Fabaceae
|
| ASCO31 | Astragalus collieri (Rydb.) Porsild | Astragalus robbinsii var. minor | Fabaceae
|
| ASCOC7 | Astragalus collinus (Hook.) Dougl. ex G. Don var. collinus | hillside milkvetch | Fabaceae
|
| ASCOL | Astragalus collinus (Hook.) Dougl. ex G. Don var. laurentii (Rydb.) Barneby | Laurent's milkvetch | Fabaceae
|
| ASCO7 | Astragalus collinus (Hook.) Dougl. ex G. Don | hillside milkvetch | Fabaceae
|
| ASCOC8 | Astragalus coltonii M.E. Jones var. coltonii | Colton's milkvetch | Fabaceae
|
| ASCOM2 | Astragalus coltonii M.E. Jones var. moabensis M.E. Jones | Moab milkvetch | Fabaceae
|
| ASCO8 | Astragalus coltonii M.E. Jones | Colton's milkvetch | Fabaceae
|
| ASCO9 | Astragalus columbianus Barneby | Columbian milkvetch | Fabaceae
|
| ASCOF3 | Astragalus confertiflorus Gray var. flaviflorus (Kuntze) M.E. Jones | Astragalus flavus | Fabaceae
|
| ASCO30 | Astragalus confertiflorus Gray | Astragalus flavus | Fabaceae
|
| ASCO10 | Astragalus congdonii S. Wats. | Congdon's milkvetch | Fabaceae
|
| ASCOC10 | Astragalus conjunctus S. Wats. var. conjunctus | Idaho milkvetch | Fabaceae
|
| ASCOO | Astragalus conjunctus S. Wats. var. oxytropidoides M.E. Jones | Astragalus hoodianus | Fabaceae
|
| ASCOR2 | Astragalus conjunctus S. Wats. var. rickardii Welsh, F. Beck & K. Caplow | Idaho milkvetch | Fabaceae
|
| ASCOS4 | Astragalus conjunctus S. Wats. var. sheldonii (Rydb.) M.E. Peck | Astragalus sheldonii | Fabaceae
|
| ASCO11 | Astragalus conjunctus S. Wats. | Idaho milkvetch | Fabaceae
|
| ASCO16 | Astragalus consobrinus (Barneby) Welsh | Bicknell's milkvetch | Fabaceae
|
| ASCO17 | Astragalus contortuplicatus L. | Hungarian milkvetch | Fabaceae
|
| ASCOC9 | Astragalus convallarius Greene var. convallarius | lesser rushy milkvetch | Fabaceae
|
| ASCOF | Astragalus convallarius Greene var. finitimus Barneby | lesser rushy milkvetch | Fabaceae
|
| ASCOF4 | Astragalus convallarius Greene var. foliolatus Barneby | Astragalus titanophilus | Fabaceae
|
| ASCOM4 | Astragalus convallarius Greene var. margaretiae Barneby | lesser rushy milkvetch | Fabaceae
|
| ASCOS | Astragalus convallarius Greene var. scopulorum Barneby | lesser rushy milkvetch | Fabaceae
|
| ASCOX | Astragalus convallarius Greene var. xiphoides Barneby | Astragalus xiphoides | Fabaceae
|
| ASCO12 | Astragalus convallarius Greene | lesser rushy milkvetch | Fabaceae
|
| ASCO32 | Astragalus cooperi Gray | Astragalus neglectus | Fabaceae
|
| ASCO18 | Astragalus cottamii Welsh | Astragalus monumentalis var. cottamii | Fabaceae
|
| ASCO13 | Astragalus cottonii M.E. Jones | Cotton's milkvetch | Fabaceae
|
| ASCO33 | Astragalus coulteri Benth. | Astragalus lentiginosus var. borreganus | Fabaceae
|
| ASCRB | Astragalus crassicarpus Nutt. var. berlandieri Barneby | groundplum milkvetch | Fabaceae
|
| ASCRC | Astragalus crassicarpus Nutt. var. cavus Barneby | groundplum milkvetch | Fabaceae
|
| ASCRC3 | Astragalus crassicarpus Nutt. var. crassicarpus | groundplum milkvetch | Fabaceae
|
| ASCRP | Astragalus crassicarpus Nutt. var. paysonii (E.H. Kelso) Barneby | groundplum milkvetch | Fabaceae
|
| ASCRT | Astragalus crassicarpus Nutt. var. trichocalyx (Nutt.) Barneby | groundplum milkvetch | Fabaceae
|
| ASCR2 | Astragalus crassicarpus Nutt. | groundplum milkvetch | Fabaceae
|
| ASCRC4 | Astragalus cremnophylax Barneby var. cremnophylax | sentry milkvetch | Fabaceae
|
| ASCRH | Astragalus cremnophylax Barneby var. hevronii Barneby | sentry milkvetch | Fabaceae
|
| ASCRM | Astragalus cremnophylax Barneby var. myriorrhaphis Barneby | sentry milkvetch | Fabaceae
|
| ASCR3 | Astragalus cremnophylax Barneby | sentry milkvetch | Fabaceae
|
| ASCR4 | Astragalus cronquistii Barneby | Cronquist's milkvetch | Fabaceae
|
| ASCRD3 | Astragalus crotalariae (Benth.) Gray var. davidsonii (Rydb.) Munz & McBurney | Astragalus preussii var. laxiflorus | Fabaceae
|
| ASCR5 | Astragalus crotalariae (Benth.) Gray | Salton milkvetch | Fabaceae
|
| ASCU3 | Astragalus curtipes Gray | Morro milkvetch | Fabaceae
|
| ASCUB | Astragalus curvicarpus (Heller) J.F. Macbr. var. brachycodon (Barneby) Barneby | curvepod milkvetch | Fabaceae
|
| ASCUC | Astragalus curvicarpus (Heller) J.F. Macbr. var. curvicarpus | curvepod milkvetch | Fabaceae
|
| ASCUS | Astragalus curvicarpus (Heller) J.F. Macbr. var. subglaber (Rydb.) Barneby | smooth loco milkvetch | Fabaceae
|
| ASCU4 | Astragalus curvicarpus (Heller) J.F. Macbr. | curvepod milkvetch | Fabaceae
|
| ASCUC2 | Astragalus cusickii Gray var. cusickii | Cusick's milkvetch | Fabaceae
|
| ASCUF | Astragalus cusickii Gray var. flexilipes Barneby | Cusick's milkvetch | Fabaceae
|
| ASCUP | Astragalus cusickii Gray var. packardiae Barneby | Packard's milkvetch | Fabaceae
|
| ASCUS2 | Astragalus cusickii Gray var. sterilis (Barneby) Barneby | barren milkvetch | Fabaceae
|
| ASCU5 | Astragalus cusickii Gray | Cusick's milkvetch | Fabaceae
|