| English Name | Scientific Name | Spanish Name |
| Acacia Fern / Whiteball Acacia Boat-thorned Acacia Bullhorn Acacia, Cockspur Sweet A., Sponge Tree Catclaw, Wait-a-minute Bush, Texas Mimosa Gum Arabic, Gum Senegal, Egyptian Thorn |
— Acacia angustissima A. cochliacantha A. cornigera A. farnesiana A. greggii A. painteriA. pennatula A. vera, A. senegal |
— Guajito, Palo de pulque, Timbe, Timben, Timbre Conchilla, Cubata prieta, Espino, Huizache Carnizuelo, Cornezuelo, Espino blanco, Vélo de novia, V. de viuda Acacia, Aromo, Binorama, Guisache, Huizache, Inu cua, Palo Huisache, Tuñú Acacia Guaje, Tepame |
| Aconite Goats Bane Aconite, Wolf’s bane, Monkshood |
— Aconitum tragoctonum A. napellus |
— Acónito Acónito, Amapelo, Matalobos |
| Agave, Century Plant, American Aloe, Maguey | — Agave americana A. guttata A. salmiana |
— Agave, Azabara, Cabuya, Calamaco, Caraguatá, Cháguar, Champagara Azul, Chuchau, Cocuyo, Cucuisa, Henequén, Lechuguilla, Maguey, Mescál, Mezcal, Penca, Pita Amole Lechuguilla, Maguey, M. chico, M. niño, M. de la sierra, Tecolote Maguey, M. pinto Mezcal blanco, Wuatusá Mezcal verde |
| Agrimony, Cocklebur | Agrimonia eupatoria | Agrimonia, Agrimoña, Cabsitilla, Cabsitiella, Cabsotella, Cabeza, Ciento en rama, Gafetí, Hierba de San Guillermo, H. bacera, H. del podador, Mermasangre |
| Airplant | — Tillandsia andrieuxii T. erubescens T. recurvata T. usneoides |
— Sirlochi Heno Heno, Gallitos, Pachtle, Paxtle, Paisté, Paistle Heno, Paiste, Paistle |
| Ajuga, Bugleweed, Carpet Weed | — Ajuga iva A. reptans |
— Iva Búgula |
| Alder Red Alder Andean Alder Common / European / Black Alder Evergreen Alder Arizona Alder |
— Alnus rubra
A. oblongifolia |
— Aliso (rojo) Aile, Aliso Aliso, A. negro, Alno Aile, Aliso, Ilite, Palo de casa, Pamu, Quina roja, Tepamo(u) Aile-powaka |
| Alfalfa, Purple Medic, Lucerne | Medicago sativa | Alfalfa, Alfaz, Mielga |
| Algerian Tea | Paronychia argentea | Nevadilla, Sanguinaria |
| Almond | — Prunus amygdalus P. triloba |
— Almendro Almendro florido |
| Aloe | — Aloe spp A. vera A. barbadensis |
— Alcibar, Sábila, Zábila Aloe, Sábila, Sávila, Zábila Acibar, Aloe vera, Sábila, Pita zabila, Zabida, Zabila, Zabira, Zadiba |
| Alpenrose | Rhododendron ferrugineum | Redodendro |
| Amaranth, Princes Feather | — Amaranthus spp A. hypochondriacus |
— Ataco, Alegria, Chile puerco, Chichilquiltic Amaranto(a), Ficaria |
| Amargo, Bitter Wood, Bitter Ash, Cuassia, Quassia | Quassia amara, Q. [Simarouba] excelsa | Cuasia, Hombre grande, Marubá, Marupá, Negrito, Palo blanco, P. amargo, Robleceillo |
| Anamu, Garlic-scented Petiveria | Petiveria alliacea | Anamú, Apacin, Apacina, Apazote, Hierba del zorrillo, Zorrillo |
| Angels Trumpet | Burgmansia x cándida | Campana, Floripondio, Florifundio, Toloache, Trombita |
| Anise Anise Burnet Saxifrage |
— Pimpinella anisum P. saxifraga |
— Anis, A. verde, Aniz, Pimpinela Pimpinella blanca |
| Annato | Bixa orellana | Achiote |
| Anoda | Anoda cristata | Alach(e), Altea, Amapolita morada, Huinarillo, Malva, M. chica, M. morada, Malvavisco, Malvón de quesitos, Requesón, Rewé, Reweque, Violeta, V. de campo, V. del país, Violetilla |
| Apple, Wild Apple, Crabapple | Pyrus mallus, Malus communis | Camueso, Maguillomaíllo, Manzana, Pero, Pomera |
| Apricot | Prunus armeniaca | Albaricoquero |
| Arbutus Arizona Madrone Mexican Strawberry Tree Strawberry Tree Texas Madrone |
— Arbutus arizonica A. glandulosa A. unedo A. xalapensis |
— Madeoño, Ulúbusi, Urúbusi Juán Pérez, Madroño Alborocera, Albornio, Árbol de las Fresas, Borrachín, Borto, Madroño, Naranjuelo Madroño, Manzanita, Ulúbsi, Urúbisi |
| Arnica, Leopardsbane | Arnica montana | Arnica |
| Arrow Root | Maranta arundinacea | Chaak |
| Artichoke Artichoke Thistle, Cardoon Globe Artichoke |
— Cynara cardunculus C. scolymus |
— Cardo Alcachofa, Alcachofera |
| Arizona Sycamore Oriental Planetree Arizona Sycamore |
— Platanus orientalis P. wrightii |
— Platano Sá, Sá aka |
| Asafoetida, Stinking Gum, Devil’s Dung | Ferula asa-foetida | Asa fétida |
| Ash — European Ash Flowering Ash Raywood Ash |
— Fraxinus spp F. excelsior F. ornus F. oxycarpa |
— Fresno Fresno de vizcaya Orno Fresno |
| Ashwaganda | Withania somniferum | Ashwagandha |
| Asparagus | Asparagus officinalis | Espárrago, Esparraguera |
| Aster | — Aster gymnocephalus A. moranensis |
— Arnica rosa Cenicilla blanca, Hojasén |
| Astralagus, Huang Qi | Astragalus membranaceus | Astrágalo |
| Avocado | Persea spp | Aguacate, Ahuacate |
| Ayahuasca | Banisteriopsis caapi | Ayahuasca, Bejuco de oro, Capi, Natema, Yagé |
