Seed plants

Acorus calamus

Acorus calamus (sweet flag, calamus, flagroot) is an aromatic Acoraceae wetland plant native to Central Asia; sterile triploid cytotypes spread via rhizomes, and β-asarone in Asian forms led to food bans in North America.

Acrocomia

Acrocomia is a genus of spiny, oil-bearing palms native from Mexico to tropical and subtropical America, best known for the macaw palm, an emerging oil crop.

Acrocomia aculeata

Acrocomia aculeata (corojo, coyol, macaúba, macaw palm) is a Neotropical oil palm from southern Mexico to Brazil and the Caribbean, IUCN Least Concern, valued for oleic-rich pulp oil and lauric-rich kernel oil and studied as a bioenergy crop.

Actaea (plant)

Actaea (baneberry, bugbane, cohosh) is a Ranunculaceae genus of 32 accepted species native to the temperate Northern Hemisphere; it absorbed Cimicifuga and Souliea in the 1998 Compton reclassification and includes black cohosh, used in herbal medicine.

Actaea racemosa

Actaea racemosa (black cohosh, Cimicifuga racemosa), a North American buttercup-family perennial whose rhizome is a popular menopause supplement; evidence for hot flashes is mixed, with rare liver injury reports and wild-harvesting concerns.

Actinidia

Actinidia (kiwifruit genus) is a genus of Asian climbing plants in Actinidiaceae, established by Lindley in 1836, with about 56 accepted species native from the Himalaya to the Russian Far East and Malesia, including the kiwifruit species A. chinensis and A. deliciosa.

Actinidia deliciosa

Actinidia deliciosa, also called Actinidia chinensis var. deliciosa or Chinese gooseberry, is the green-fleshed fuzzy kiwifruit vine native to China, commercialized in New Zealand from 1904 seeds and renamed kiwifruit in 1959.

Actinidiaceae

Actinidiaceae, the Chinese gooseberry family, is an Ericales family of three genera, Actinidia, Saurauia, and Clematoclethra, with about 350-400 species of Asian and American trees, shrubs, and lianas, including the kiwifruit.

Adansonia

Adansonia (baobab) is a genus of eight massive Malvaceae trees: A. digitata in Africa, A. gregorii in Australia, six endemic to Madagascar; genomic studies trace the origin to Madagascar about 41 million years ago.

Adansonia digitata

Adansonia digitata, the African baobab or upside-down tree, is a massive long-lived Malvaceae tree of dry Africa and Arabia; fruit pulp rich in vitamin C, over 300 traditional uses, IUCN Least Concern, Madagascar-origin genus.

Adelgidae

Adelgidae (pine aphids, spruce aphids; synonym Chermidae) is a small Aphidoidea family of about 65-70 conifer-feeding, gall-forming, cyclically parthenogenetic Hemiptera, including the hemlock and balsam woolly adelgid forest pests.

Adenium obesum

Adenium obesum, the desert rose (basionym Nerium obesum), is a semisucculent Apocynaceae shrub from West Tropical Africa to the Arabian Peninsula and Tanzania, with a swollen caudex, poisonous sap, IUCN Least Concern status, and widespread ornamental cultivation.

Adenophora

Adenophora Fisch. (ladybells) is a Campanulaceae genus of perennial herbs native from temperate Eurasia to Indo-China, defined by a nectar disk between stamens and pistils; about 68 species, revised phylogenomically in 2025. Distinct from Ageratina adenophora.

Adina

Adina Salisb. (水團花屬) is a genus of 12 accepted species of shrubs and small trees in Rubiaceae, tribe Naucleeae, native to tropical and subtropical Asia, with dense spherical flower heads; includes haldu (A. cordifolia) and Chinese buttonbush (A. pilulifera).

Adonis vernalis

Adonis vernalis (spring pheasant's eye, false hellebore) is a poisonous Eurasian Ranunculaceae perennial containing cardenolide cardiac glycosides, used as a cardiotonic since 1879 and now CITES-listed and endangered in parts of Europe.

Aechmea

Aechmea (livingvase) is a large, polyphyletic bromeliad genus (Bromeliaceae, Bromelioideae) of tank-forming rosette plants native from Mexico to tropical America, with about 255 species including the popular urn plant Aechmea fasciata.

Aechmea fasciata

Aechmea fasciata, the urn plant or silver vase, is an evergreen bromeliad from Brazil grown worldwide as a houseplant for its banded leaves and pink flower head.

Aegilops

Aegilops (goatgrass) is a genus of about 22-23 annual grasses in Poaceae, tribe Triticeae, native from Macaronesia and the Mediterranean to western Himalaya and central China, and the wild relative that donated wheat's B, G, and D genomes.

Aegilops tauschii

Aegilops tauschii (goat grass, Tausch's goatgrass) is an annual Eurasian grass, diploid DD, that hybridized with tetraploid wheat about 8,000-11,000 years ago to create bread wheat's D genome and now serves as a breeding resource.

Aegle

Aegle is a monotypic genus of Rutaceae (Sapindales) whose single species, Aegle marmelos (bael, Bengal quince), is a spiny South Asian tree with hard-shelled aromatic fruit, sacred in Hinduism and used in Ayurveda.

Aegle marmelos

Aegle marmelos (bael, bilva, Bengal quince) is a spiny Rutaceae tree native to the Indian Subcontinent, sacred in Hinduism and used in Ayurveda; fruit 5–15 cm, bioactives include marmelosin and aegeline.

Aegopodium

Aegopodium (羊角芹属), goutweed or ground elder genus, Apiaceae herbs native to temperate Eurasia and the Himalaya; 12 accepted species; A. podagraria is an invasive rhizomatous garden weed in North America.

Aegopodium podagraria

Aegopodium podagraria, goutweed or ground elder (bishop's weed), is a rhizomatous Apiaceae perennial native to temperate Eurasia, a medieval potherb and gout remedy, now an invasive ornamental spreading by rhizomes up to 70 cm yearly.

Aeschynomene

Aeschynomene L. (joint vetch) is a pantropical legume genus of about 150-190 species, many aquatic, famous for stem nodulation by photosynthetic Bradyrhizobium lacking nodABC genes; A. evenia is its Nod-independent model legume.

Aesculus

Aesculus (horse-chestnuts, buckeyes) is a genus of about 12 tree and shrub species in Sapindaceae, native from SE Europe to Japan and North America, containing the toxin aesculin and including the widely planted European horse-chestnut.

Aesculus glabra

Aesculus glabra, Ohio buckeye (fetid or stinking buckeye), a Sapindaceae tree of the east-central US with five-leaflet palmate leaves, spiny capsules, toxic aesculin/aescin seeds, soft light wood, and status as Ohio's state tree.

Aesculus hippocastanum

Aesculus hippocastanum, horse chestnut or conker tree, is a large Balkan-native deciduous tree, IUCN Vulnerable with 5,000-9,000 mature trees, threatened by the leaf miner Cameraria ohridella and used medicinally via escin seed extract.

Aframomum

Aframomum K.Schum., a genus of about 63 accepted species of rhizomatous Zingiberaceae herbs native to tropical Africa and Madagascar; includes A. melegueta, grains of paradise or alligator pepper, a West African spice and medicinal plant.

Afrocarpus

Afrocarpus is a small genus of African yellowwood conifers, evergreen dioecious trees of Afromontane forests from Ethiopia south to the Cape, with 5 to 7 species.