4,295 articles
Hymenaea
Hymenaea (jatobá) is a genus of resin-producing legume trees of tropical America and East Africa; H. courbaril yields hard timber, edible pulp, and copal resin, and Hymenaea resin produced Mexican, Dominican, and Ethiopian Miocene ambers.
Hymenaea courbaril
Hymenaea courbaril (jatobá, West Indian locust) is a 30-50 m Neotropical legume tree from Mexico to southeastern Brazil, yielding copal resin, dense timber, and starchy edible pod pulp; formerly six varieties, split into three species in 2014.
Hymenophyllaceae
Hymenophyllaceae, the filmy ferns, are a fern family of roughly 430 to more than 600 species, mostly tropical, whose fronds are only a single cell thick between the veins.
Hymenophyllales
Hymenophyllales, the filmy ferns, is an order of leptosporangiate ferns with the single family Hymenophyllaceae; fronds one or few cells thick, no stomata, over 600 species, mostly tropical rainforest epiphytes.
Hymenophyllum
Hymenophyllum, the filmy fern genus of Hymenophyllaceae, has 316 accepted species with one-cell-thick, stomata-free fronds, bivalved sori, cosmopolitan humid-forest range, and poikilohydric desiccation tolerance.
Hymenophyllum australe
Hymenophyllum australe (Austral filmy fern), formerly H. atrovirens in New Zealand, is a Hymenophyllaceae fern native to SE Australia, New Zealand, and Vanuatu, growing on rocks near streams or as an epiphyte in wet montane forests; fronds 6–20 cm, n=36.
Hymenophyllum tunbrigense
Hymenophyllum tunbrigense, Tunbridge filmy fern, a filmy fern of Hymenophyllaceae with toothed-indusium spore cases, bluish-green 2-10 cm fronds, disjunct Europe-Africa-Tristan da Cunha range, and sharp southeastern England decline.
Hyoscyamus
Hyoscyamus (henbane) is a Solanaceae genus of about 23 herb species native from Macaronesia and Africa to temperate Eurasia, source of tropane alkaloids hyoscyamine, scopolamine, and tropine; sister genus Anisodus, type species H. niger.
Hyoscyamus niger
Hyoscyamus niger (black henbane, stinking nightshade, tian xian zi) is a poisonous Solanaceae herb native from the Mediterranean to Iran, containing the tropane alkaloids hyoscyamine and scopolamine, used since antiquity as a sedative and analgesic.
Hyparrhenia
Hyparrhenia (thatching grass) is an African-centered genus of about 58 accepted C4 grasses in tribe Andropogoneae, family Poaceae, valued for thatch and young forage, with H. rufa, H. hirta, and H. filipendula the best-known species.
Hypericaceae
Hypericaceae, the St. John's wort family (Hypericaceae Juss., 1789), is a Malpighiales family of herbs and shrubs with gland-dotted leaves; its dominant genus Hypericum holds 521 species, and sister family is Podostemaceae.
Hypericum
Hypericum (St. John's worts), genus of Hypericaceae with about 500 yellow-flowered species of herbs and shrubs, cosmopolitan mainly in temperate regions; includes medicinal H. perforatum and invasive weeds.
Hypericum perforatum
Hypericum perforatum (St. John's wort, Klamath weed) is a perennial Hypericaceae herb native from Europe to China and NW Africa, used for mild to moderate depression; extracts show efficacy near standard antidepressants but induce CYP3A4 and P-glycoprotein, causing major drug interactions.
Hyphaene
Hyphaene (doum palms), genus of dioecious coryphoid palms native from tropical and southern Africa to Sri Lanka, unique for dichotomously branching trunks; about 8 species, edible fruits, Eocene origin, difficult taxonomy with many synonyms.
Hyphaene thebaica
Hyphaene thebaica, the doum or gingerbread palm (دوم), is a branching dioecious African palm from West Africa to Arabia, with hard edible fruits rich in fiber, potassium, and phenolics, sacred in ancient Egypt.
Hypnales
Hypnales, the largest order of mosses (about 4,200 species), pleurocarpous feather and fern mosses; formerly included Leucodontales and Hypnobryales; rapid early radiation, Gondwanan origin, sister order Hookeriales.
Hypnodendrales
Hypnodendrales (Bell, Newton & Quandt, 2007) is an order of pleurocarpous mosses in superorder Hypnanae, sister to Ptychomniales, Hookeriales, and Hypnales; families include Hypnodendraceae, Racopilaceae, Pterobryellaceae, with mainly tropical, Gondwanan distribution.
Hypnum
Hypnum, a genus of pleurocarpous mosses in Hypnaceae typified by Hypnum cupressiforme (cypress-leaved plaitmoss). Once defined by falcate leaves and a short double costa, molecular work showed it polyphyletic; now restricted to the H. cupressiforme complex, widely used in metal biomonitoring.
Hypolepis
Hypolepis, known as beadfern or bramble fern, is a genus of coarse terrestrial ferns in Dennstaedtiaceae, recognized by long-creeping rhizomes, prickly scrambling fronds, and round sori at the frond margin.
Hyptis
Hyptis (Jacq., 1787) is a conserved Lamiaceae genus of 169 accepted species native to tropical and subtropical America, introduced across Africa and Asia; aromatic, terpene-rich, including H. suaveolens and H. capitata, the type species.
Hyssopus officinalis
Hyssopus officinalis (hyssop), Mediterranean mint-family herb with blue-violet flowers; culinary flavoring and Chartreuse ingredient; pinocamphone-containing essential oil is convulsant; one asthma trial.
Iberis
Iberis, commonly candytuft, is a Mediterranean genus of about 30 species in Brassicaceae, tribe Iberideae, native from western Europe to Iran; I. sempervirens is the familiar evergreen white-flowered ground cover.
Icacinaceae
Icacinaceae Miers (1851), a pantropical family of woody flowering plants in Icacinales; trees, shrubs, and lianas with unilocular ovaries and two pendulous ovules, split from a polyphyletic circumscription into Icacinaceae s.s., Stemonuraceae, Cardiopteridaceae, and Pennantiaceae.
Iceberg lettuce
Iceberg lettuce, also called crisphead (Lactuca sativa var. capitata), is a tight-headed, 95%-water lettuce named for ice-cooled rail shipping. Lower in nutrients than romaine; linked to the record 2026 U.S. Cyclospora outbreak.
Iizuka Shōkansai
Iizuka Shōkansai (飯塚 小玕斎, 1919–2004), real name Iizuka Shigetoshi, was a Japanese bamboo weaving artist named a Living National Treasure in 1982, the second bamboo artist so honored.
Ilex
Ilex, the hollies, is the sole genus of the flowering plant family Aquifoliaceae, with about 730 dioecious, mostly evergreen tree and shrub species, including yerba mate.
Ilex aquifolium
Ilex aquifolium, common or English holly (欧洲冬青), an evergreen dioecious Aquifoliaceae tree native to Europe, NW Africa and W Asia; spiny leaves, red drupes, IUCN Least Concern, invasive in Pacific Northwest, New Zealand, SE Australia.
Illicium
Illicium (anisetree, star anise) is a genus of about 40 aromatic evergreen shrubs and trees in Schisandraceae, order Austrobaileyales, native from the Himalaya to Japan and the southeastern United States to Mexico and the Caribbean; only I. verum is edible, other species contain neurotoxic sesquiterpene lactones such as anisatin.
Illicium verum (八角)
Illicium verum (八角, ba jiao hui xiang), star anise or Chinese star anise, an evergreen Schisandraceae tree native to southern China and northeast Vietnam; its dried star fruit yields trans-anethole oil and shikimic acid for oseltamivir, and is adulterated by toxic I. anisatum.
Impatiens
Impatiens (balsams, touch-me-nots), genus of Balsaminaceae with 1,187 accepted species, native to the Old World and the Americas, known for explosive seed capsules, ornamental busy Lizzies, and invasive Himalayan balsam.