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Hemp oil
Hemp oil (hemp seed oil) is the culinary oil pressed from Cannabis sativa seeds, naturally free of THC and CBD, GRAS-recognized by FDA in 2018, and distinct from hemp-derived CBD oil extracted from flowers and leaves.
Heracleum (plant)
Heracleum, commonly known as hogweed or cow parsnip, is a genus of about 90 herbs in the carrot family native to the temperate Northern Hemisphere, some reaching 18 ft.
Heracleum mantegazzianum
Heracleum mantegazzianum, giant hogweed, is a 5 m tall monocarpic Apiaceae herb native to the Western Greater Caucasus, invasive in Europe and North America, whose furanocoumarin sap causes phototoxic dermatitis.
Heracleum sphondylium
Heracleum sphondylium, common hogweed or cow parsnip, is a native European Apiaceae herb, 0.3-1.5 m tall with blunt leaves and small umbels, only weakly phototoxic, unlike giant hogweed.
Herb
Herb: botanically, a non-woody plant whose stem dies back yearly; in common use, plants used for flavoring, medicine, and perfume. Key facts: fresh-to-dried ratio 3:1, 0 C storage, USD 5.9 billion fresh herb market.
Herniaria
Herniaria (ruptureworts) is a genus of prostrate Caryophyllaceae herbs published by Linnaeus in 1753, type species H. glabra, with about 52 accepted species from Europe to Central Asia and Africa, traditionally used for hernias and kidney stones.
Hesperis matronalis
Hesperis matronalis, dame's rocket or dame's violet, is a Eurasian biennial mustard with fragrant four-petaled purple or white flowers, widely naturalized and invasive in North America, attacked by the weevil Ceutorhynchus inaffectatus, and often confused with five-petaled garden phlox.
Hevea
Hevea is a genus of ten Euphorbiaceae tree species native to South Tropical America; Hevea brasiliensis, the rubber tree, supplies all commercial natural rubber, used mainly in tires, with guayule and dandelion as alternatives.
Hibiscus
Hibiscus is a genus of about 200–438 species in Malvaceae, tribe Hibisceae, native to tropics and subtropics, known for showy flowers, ornamental and fiber uses, and roselle (H. sabdariffa) tea; molecular studies show the genus is polyphyletic.
Hibiscus syriacus
Hibiscus syriacus, rose of Sharon or shrub althea, is a deciduous Malvaceae shrub native to southern China and Taiwan, the national flower of South Korea, hardy to USDA zone 5, with white-to-purple summer flowers and many cultivars.
Hickory
Hickory (Carya, Juglandaceae): about 16 hardwood species native to Asia, Central America, and North America, prized for shock-resistant tool-handle wood and oil-rich nuts; European species went extinct in the Ice Age.
Hieracium
Hieracium (hawkweeds) is a large Asteraceae genus of perennial herbs with yellow flowerheads, 4,614 accepted species, apomictic polyploids, and a split-off relative genus Pilosella; Mendel's later experimental plant.
Hippocrepis
Hippocrepis (horseshoe vetches) is a genus of 34 Fabaceae species in tribe Loteae, native Europe to Pakistan and Macaronesia to Arabia, with curved lomentaceous pods; type-era name from Linnaeus 1753.
Hippophae
Hippophae (sea buckthorn, 沙棘属), spiny dioecious Elaeagnaceae shrubs with seven species from Europe to the Himalaya; H. rhamnoides fixes nitrogen via Frankia and yields vitamin-rich, omega-7 oil berries bred into over 150 cultivars.
Hippophae rhamnoides
Hippophae rhamnoides, sea buckthorn (Elaeagnaceae), a hardy nitrogen-fixing Eurasian shrub with seven subspecies, orange vitamin-rich berries used in food and traditional medicine, and limited clinical evidence of benefit.
History of cannabis
History of cannabis (Cannabis sativa): Eurasian domestication for fiber, food, and medicine; earliest psychoactive use at Jirzankal Cemetery; O'Shaughnessy's 19th-century medical promotion; 1925 Geneva control, 1937 US Marijuana Tax Act, and modern legalization.
History of the potato
History of the potato (Solanum tuberosum): Andean domestication ~10,000 years ago, sixteenth-century Spanish introduction to Europe, Chilean subspecies adoption, the Great Irish Famine, demographic effects, and modern genome-based breeding.
Holly
Holly (Ilex, Aquifoliaceae): the sole genus of its family, over 664 dioecious tree and shrub species. Originated in subtropical Asia in the early Eocene; famous species include Ilex aquifolium, the Christmas holly.
Holodiscus discolor
Holodiscus discolor, oceanspray or creambush (Rosaceae), a deciduous arching shrub native from British Columbia to Mexico, with creamy white flower sprays, four varieties, fire-adapted, valuable to native bees.
Honey locust
Honey locust (Gleditsia triacanthos), also called sweet-locust or thorny-locust, is a thorned North American legume tree with sweet pods, thornless urban cultivars, and invasive populations in Argentina, Europe, and Australia.
Honeysuckle
Honeysuckle, genus Lonicera (Caprifoliaceae), about 160 Northern Hemisphere species of fragrant vines and shrubs; Japanese honeysuckle (Lonicera japonica) is a major invasive vine in North America, while Lonicera sempervirens is a native alternative.
Hopea
Hopea is a genus of about 100 dipterocarp timber trees from Sri Lanka to New Guinea, known as merawan timber, distinguished from Shorea by two long fruit calyx wings and nested phylogenetically within Shorea.
Hops
Hops, the female cones of Humulus lupulus (Cannabaceae), are the brewing crop that bitters, flavors, and preserves beer via alpha acids and essential oils; cultivated since the 8th-century Hallertau, with over 260 varieties and medicinal uses.
Hornbeam
Hornbeam (Carpinus), a birch-family hardwood genus of about 19-40 Northern hemisphere species; European hornbeam (C. betulus) is a 25 m coppice and hedging tree of heavy lowland soils, with very hard wood used for cogs and mallets.
Horseradish
Horseradish (Armoracia rusticana), a Brassicaceae perennial from southeastern Europe and western Asia, grown over 3,000 years for its pungent taproot; allyl isothiocyanate from sinigrin gives the heat, and it substitutes for wasabi.
Houstonia caerulea
Houstonia caerulea, the azure bluet or Quaker ladies, is a small wildflower of the madder family native to eastern North America, with pale blue, four-lobed spring flowers.
Houttuynia cordata
Houttuynia cordata (chameleon plant, fish mint, yu xing cao) is an Asian Saururaceae herb eaten as a vegetable, used in traditional Chinese medicine, studied for anti-inflammatory and antiviral effects, and invasive outside its native range.
Humulus
Humulus (hops genus) is a Cannabaceae genus of dioecious twining herbs native to the temperate Northern Hemisphere, with 7 accepted species; H. lupulus cones supply beer bitterness, aroma, and preservation.
Humulus lupulus
Humulus lupulus, common hop, is a dioecious perennial Cannabaceae vine whose female cones (strobili) supply beer's bitterness and aroma; ~97% of production goes to brewing, with humulone, xanthohumol, and 8-prenylnaringenin as key compounds.
Hura crepitans
Hura crepitans, the sandbox tree or jabillo, is a spiny Euphorbiaceae tree native to tropical America with toxic sap and explosive fruit capsules that launch seeds at about 43 m/s up to 45 m.