| scientific name | common name(s) | image gallery |
| Acer leucoderme | Chalk maple | |
| Acer saccharum | Sugar maple | |
| Adiantum pedatum | Northern maidenhair Maidenhair Fern | |
| Aesculus pavia | Scarlet Buckeye Red buckeye | |
| Aesculus parviflora | Bottlebrush buckeye | |
| Ageratina altissima var. altissima | White snakeroot | |
| Amorpha fruticosa | Indigo bush False indigo bush False indigo Desert false indigo | |
| Amelanchier stolonifera | Running serviceberry | |
| Amsonia tabernaemontana | Eastern bluestar Blue dogbane Willow amsonia Woodland bluestar | |
| Aquilegia canadensis | Eastern red columbine Wild red columbine | |
| scientific name | common name(s) | image gallery |