herbicide

herbicide
herbicidal, adj.
/herr"beuh suyd', err"-/, n.
a substance or preparation for killing plants, esp. weeds.
[1895-1900; HERB + -I- + -CIDE]

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Agent, usually chemical, for killing or inhibiting the growth of unwanted plants (weeds).

Modern weed killers are put in two categories, selective (affecting specific plant species) and nonselective (affecting plants generally). These in turn are classified as foliage-applied and soil herbicides. Contact herbicides (e.g., sulfuric acid, diquat, paraquat) kill only the plant organs with which they are in contact. Translocated herbicides (e.g., amitrole, picloram, 2,4-D) are effective against roots or other organs, to which they are transported from aboveground treated surfaces (soil). See also defoliant.

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      an agent, usually chemical, for killing or inhibiting the growth of unwanted plants—i.e., weeds. (See weed.) In the past, sea salt, by-products of chemical industries, and various oils were used as weed killers. Late in the 19th century the selective control of broad-leaved weeds among cereal crops came into practice. The central development in modern weed control was the introduction in 1945 of so-called organic herbicides; they were revolutionary in that their high toxicity allowed for effective weed control at very low dosages—about 1–2 percent of the dosage rates of such earlier weed killers as carbon disulfide, borax, and arsenic trioxide.

      Modern weed killers are put in two categories: selective (affecting specific plant species) and nonselective (affecting plants generally). These, in turn, are classified as foliage-applied and soil herbicides. Contact herbicides (e.g., sulfuric acid, diquat, paraquat) kill only the plant organs with which they are in contact. Translocated herbicides (e.g., amitrole; picloram; 2,4-D) are effective against roots or other organs to which they are transported from aboveground treated surfaces (i.e., soil). With respect to planting time, herbicides are also classified as preplant, preemergence, or postemergence weed killers. Preplant herbicides may be applied to the soil or to weeds before crop planting.

      Certain herbicides (e.g., sodium arsenite) are sometimes applied by the jar method, whereby the tops of weeds are bent over and immersed in jars of poisonous solution. The herbicide is drawn into the rest of the plant and into connecting plants, gradually killing the entire system. Wild morning glory, poison oak, and camel thorn are sometimes treated in this manner. Chlorinated benzene and certain aromatic solvents are used to control aquatic weeds by adding them directly to the watery medium. See also defoliant.

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Universalium. 2010.

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Look at other dictionaries:

  • herbicide — [ ɛrbisid ] adj. et n. m. • v. 1930; de herbe et cide ♦ Didact. Qui détruit les mauvaises herbes. Produit herbicide. N. m. Un herbicide. ⇒ pesticide; débroussaillant, défoliant, désherbant. ● herbicide adjectif et nom masculin Se dit d un produit …   Encyclopédie Universelle

  • herbicide — herbicide. См. гербицид. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • herbicide — 1888, originally a trademark name, from HERB (Cf. herb) + CIDE (Cf. cide) …   Etymology dictionary

  • herbicide — [n] poison DDT, defoliant, fungicide, insecticide, paraquat, pesticide, weedkiller; concepts 307,475,674,675 …   New thesaurus

  • herbicide — ► NOUN ▪ a toxic substance used to destroy unwanted vegetation …   English terms dictionary

  • herbicide — [hʉr′bə sīd΄, ʉr′bə sīd΄] n. [herbi (< L herba, HERB) + CIDE] any chemical substance used to destroy plants, esp. weeds, or to check their growth herbicidal adj …   English World dictionary

  • Herbicide — Weeds killed with herbicide Herbicides, also commonly known as weedkillers, are pesticides used to kill unwanted plants.[1] Selective herbicides kill specific targets while leaving the desired crop relatively unharmed. Some of these act by… …   Wikipedia

  • Herbicide — Dans la famille des pesticides[1], elle même incluse dans la famille des biocides[2], on appelle herbicide toute substance active ou une préparation ayant la propriété de tuer les végétaux. Le terme « désherbant » est un synonyme d… …   Wikipédia en Français

  • herbicide — UK [ˈhɜː(r)bɪsaɪd] / US [ˈɜrbɪˌsaɪd] noun [countable/uncountable] Word forms herbicide : singular herbicide plural herbicides a chemical used for killing weeds (= plants that are not wanted) …   English dictionary

  • herbicide — [[t]hɜ͟ː(r)bɪsaɪd, AM ɜ͟ː(r)b [/t]] herbicides N MASS A herbicide is a chemical that is used to destroy plants, especially weeds …   English dictionary

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