| scientific name | common name(s) | image gallery |
| Acacia berlandieri | Berlandier acacia Guajillo | |
| Acacia farnesiana | Huisache Sweet acacia Mealy wattle | |
| Acacia greggii var. wrightii | Catclaw acacia Catclaw Wright acacia | |
| Achillea millefolium | Common yarrow Yarrow Milfoil Western yarrow | |
| Acleisanthes obtusa | Berlandier's trumpets Vine four-o’clock | |
| Acalypha radians | Cardinal feather Cardinal's feather | |
| Acanthocereus tetragonus | Triangle Cactus Barbed-wire Cactus Chaco | |
| Aesculus pavia | Scarlet Buckeye Red buckeye | |
| Agave americana | American century plant Century plant | |
| Agave havardiana | Havard's century plant Havard agave | |
| scientific name | common name(s) | image gallery |