Abies, Genus
Abutilon, Genus
Acer, Genus
Aceraceae, Family
– synoniem van Sapindaceae, Family
Achillea, Genus
Aconitum, Genus
Acoraceae, Family
Acorales, Order
Acorus, Genus
Actaea, Genus
Actinidia, Genus
Actinidiaceae, Family
Adiantum, Genus
Adonis, Genus
Adoxa, Genus
Adoxaceae, Family
Aegopodium, Genus
Aesculus, Genus
Aethusa, Genus
Agastache, Genus
Agrimonia, Genus
Agrostemma, Genus
Agrostis, Genus
Ailanthus, Genus
Aira, Genus
Ajuga, Genus
Alcea, Genus
Alchemilla, Genus
Alisma, Genus
Alismataceae, Family
Alismatales, Order
Alliaceae, Family
Alliaria, Genus
Allium, Genus
Alnus, Genus
Alopecurus, Genus
Althaea, Genus
Alyssum, Genus
Amaranthaceae, Family
Amaranthus, Genus
Amaryllidaceae, Family
Ambrosia, Genus
Amelanchier, Genus
Ammi, Genus
Ammophila, Genus
Amsinckia, Genus
Anacamptis, Genus
Anacardiaceae, Family
Anagallis, Genus
Anaphalis, Genus
Anchusa, Genus
Andromeda, Genus
Anemone, Genus
Anethum, Genus
Angelica, Genus
Anisantha, Genus
ANITA-groep, Order
Anoda, Genus
Antennaria, Genus
Anthemis, Genus
Anthericum, Genus
Anthoxanthum, Genus
Anthriscus, Genus
Anthyllis, Genus
Antirrhinum, Genus
Apera, Genus
Aphanes, Genus
Apiaceae, Family
Apiales, Order
Apium, Genus
Apocynaceae, Family
Aquifoliaceae, Family
Aquifoliales, Order
Aquilegia, Genus
Arabidopsis, Genus
Arabis, Genus
Aracae, Family
Araceae, Family
Aralia, Genus
Araliaceae, Family
Arctium, Genus
Arctostaphylos, Genus
Arenaria, Genus
Aristolochia, Genus
Aristolochiaceae, Family
Armeria, Genus
Armoracia, Genus
Arnica, Genus
Arnoseris, Genus
Aronia, Genus
Arrhenatherum, Genus
Artemisia, Genus
Arum, Genus
Aruncus, Genus
Asclepiadaceae, Family
– synoniem van Apocynaceae, Family
Asclepias, Genus
Asparagaceae, Family
Asparagales, Order
Asparagus, Genus
Asperugo, Genus
Asperula, Genus
Aspidiaceae, Family
– synoniem van Dryopteridaceae, Family
Aspleniaceae, Family
Asplenium, Genus
Aster, Genus
Asteraceae, Family
Asterales, Order
Astragalus, Genus
Athyriaceae, Family
Athyrium, Genus
Atriplex, Genus
Atropa, Genus
Aubrieta, Genus
Avena, Genus
Axyris, Genus
Azolla, Genus
Azollaceae, Family
– synoniem van Salviniaceae, Family