2,112 articles
Ardisia
Ardisia (marlberry) is a genus of about 740 accepted species in Primulaceae, pantropical trees and shrubs with gland-dotted leaves and one-seeded drupes, widely used in traditional medicine and including invasive species such as A. crenata.
Arenaria (plant)
Arenaria (Caryophyllaceae), sandworts, a genus of small mat-forming herbs with 5-merous white or pink flowers and toothed capsules; about 180 species in temperate and alpine Northern Hemisphere habitats, taxonomy reshaped by molecular phylogenetics.
Argan oil
Argan oil, a plant oil from kernels of the endemic argan tree (Argania spinosa) of southwest Morocco; UNESCO-listed traditional extraction, oleic/linoleic-rich composition, γ-tocopherol, schottenol and spinasterol sterols, and the world's most expensive vegetable oil.
Argemone
Argemone, prickly poppy (Mexican poppy, Argemone mexicana), a Papaveraceae genus of 33 spiny yellow-sapped herbs native to the Americas and Hawaii; A. mexicana seed oil causes epidemic dropsy.
Argemone mexicana
Argemone mexicana (Mexican prickly poppy, cardo santo), a prickly annual Papaveraceae herb native to Central America, pantropical weed and medicinal plant whose sanguinarine-rich seed oil causes epidemic dropsy when it adulterates mustard oil.
Argentina anserina
Argentina anserina (silverweed, silverweed cinquefoil; formerly Potentilla anserina) is an allotetraploid stoloniferous Rosaceae perennial of temperate wetlands across the Northern Hemisphere, invasive in Patagonia, IUCN least concern.
Argyreia nervosa
Argyreia nervosa, Hawaiian baby woodrose or elephant creeper, is a Convolvulaceae liana native to the Indian subcontinent to Myanmar whose seeds contain 0.5–0.9% ergoline alkaloids including LSA, giving LSD-like but sedating effects.
Aria torminalis
Aria torminalis, the wild service tree (syn. Sorbus torminalis, Torminalis glaberrima), is a suckering Rosaceae tree of Europe to Iran and NW Africa, with chequer fruits, prized timber, and IUCN Least Concern status.
Ariocarpus retusus
Ariocarpus retusus (star rock, living rock, false peyote) is the type species of the living rock cacti, a spineless grey cactus from northeastern Mexico, 10–25 cm across, white autumn flowers, IUCN Least Concern but CITES Appendix I.
Ariocarpus scaphirostris
Ariocarpus scaphirostris (also spelled scaphirostrus), the Nuevo León living-rock cactus, is an endangered CITES Appendix I cactus endemic to Nuevo León, Mexico, with boat-shaped tubercles and a population down over 80% in 20 years.
Aristolochia
Aristolochia (birthwort, Dutchman's pipe) is a cosmopolitan genus of about 350–569 species in Aristolochiaceae with trap flowers pollinated by flies, containing carcinogenic aristolochic acids.
Aristolochiaceae
Aristolochiaceae, the birthwort family (Aristolochiaceae Juss., 1789), is a Piperales family of climbers and herbs including Aristolochia and Asarum, known for trap-pollinated flowers and nephrotoxic, carcinogenic aristolochic acids.
Armeria
Armeria (thrift, sea pink) is a genus of about 100–260 perennial Plumbaginaceae herbs with basal rosettes and globose flower heads, centered in the Mediterranean; Italy is its second biodiversity hotspot with 10 endemic species per a 2026 revision.
Arnica
Arnica, a Northern Hemisphere genus of about 31 Asteraceae species, is the source of Arnica montana, used externally for bruises and sprains; internal use is toxic and homeopathic efficacy is unproven.
Arnica montana
Arnica montana (mountain arnica, Echte Arnika) is a European Asteraceae perennial whose yellow flower heads yield helenalin sesquiterpene lactones used topically for bruises and sprains; endangered in Germany, CITES-listed, EU traditional-use herbal monograph.
Aronia
Aronia, known as chokeberry or chokeberries, is a genus of deciduous shrubs in the rose family native to eastern North America, grown for its dark, polyphenol-rich fruit used in juice and wine.
Aronia melanocarpa
Aronia melanocarpa (black chokeberry) is a North American Rosaceae shrub grown for astringent, polyphenol- and anthocyanin-rich berries used in juices and functional foods; human RCT meta-analyses show no significant cardiometabolic effects.
Arracacia xanthorrhiza
Arracacia xanthorrhiza (arracacha, Peruvian parsnip) is an Andean Apiaceae herb domesticated about 3000 years ago for its starchy storage root, grown at 600–3600 m in Brazil, Colombia, and other Andean countries, propagated by cormels.
Artemisia
Artemisia, known as wormwood, mugwort, and sagebrush, is a genus of about 540 aromatic herbs and shrubs in the daisy family, source of the antimalarial drug artemisinin.
Artemisia absinthium
Artemisia absinthium (wormwood, absinthium), Asteraceae perennial of Europe to Siberia, W. Himalaya, N. Africa; source of absinthe's thujone, EMA traditional use for appetite loss and dyspepsia, invasive in North America.
Artemisia annua
Artemisia annua (qinghao), annual Asteraceae herb native from North Africa to Eurasia; sole natural source of the antimalarial sesquiterpene artemisinin, made in glandular trichomes and the basis of ACT drugs.
Artemisia tridentata
Artemisia tridentata, big sagebrush, is an aromatic evergreen Asteraceae shrub dominating 62 million hectares of western North America, with basin, mountain, and Wyoming subspecies on distinct soils and elevations, killed by fire and regenerating only from seed.
Artemisia vulgaris
Artemisia vulgaris, common mugwort (ai-yeh, moxa), a perennial Asteraceae herb native to temperate Eurasia and North Africa, naturalized in North America; medicinal and culinary herb with thujone limits, allergy risk, and invasive status in the northeastern US.
Artocarpus
Artocarpus (breadfruit genus) is a Moraceae tree genus of about 70 species from tropical Asia to the western Pacific, with Borneo as its ancestral range; it yields jackfruit, breadfruit, cempedak, and marang, with compound syncarp fruits up to 45 kg.
Artocarpus integer
Artocarpus integer, cempedak (champada, chempedak), a Moraceae fruit tree native from Peninsula Thailand to Malesia, related to jackfruit and breadfruit; aromatic 0.6–3.5 kg fruits, teak-strength timber, IUCN Least Concern.
Aruncus
Aruncus (goat's beard) is a genus of five accepted dioecious perennial species in Rosaceae, native to the temperate Northern Hemisphere; A. dioicus grows 3-6 ft with creamy plumes, A. aethusifolius is a 12-inch Korean dwarf.
Asarum
Asarum (wild ginger) is a genus of about 138 accepted species of aromatic rhizomatous herbs in Aristolochiaceae, native to the temperate Northern Hemisphere, most diverse in East Asia, used as the Chinese medicine Xixin but containing nephrotoxic aristolochic acid analogs.
Asarum europaeum
Asarum europaeum (asarabacca, European wild ginger), Aristolochiaceae perennial native from Europe to Central Siberia; evergreen ground cover with hidden flowers; contains toxic, carcinogenic aristolochic acid.
Asclepias
Asclepias, commonly known as milkweeds, is a genus of about 130 plants in the dogbane family. These herbaceous perennials are a major host plant for monarch butterflies.
Asclepias curassavica
Asclepias curassica, or tropical weed, is a flowering plant native to Mexico. It is grown as an ornamental and serves as a host for the monarch butterfly.