| scientific name | common name(s) | image gallery |
| Abies concolor | Balsam fir Colorado fir Concolor fir Oyamel de California Silver fir White balsam White fir | |
| Abies magnifica | California red fir Red fir | |
| Abronia villosa | Desert sand verbena Desert sand-verbena Desert sandverbena | |
| Acacia greggii | Catclaw acacia Gregg acacia Long-flower catclaw | |
| Achnatherum hymenoides | Indian ricegrass Indian Millet Sandgrass | |
| Acer macrophyllum | Bigleaf maple Big-leaf maple | |
| Adenostoma fasciculatum | Chamise Common chamise Greasewood | |
| Adenostoma sparsifolium | Redshank Ribbon bush Ribbonwood | |
| Aesculus californica | California buckeye | |
| Amelanchier alnifolia | Saskatoon serviceberry Western serviceberry Juneberry | |
| scientific name | common name(s) | image gallery |