Grazing

Grazing

Grazing generally describes a type of predation in which an herbivore feeds on plants (such as grasses), or more broadly on a multicellular autotrophs (such as kelp). Grazing differs from true predation because the organism being eaten is not killed, and it differs from parasitism as the two organisms do not live together, nor is the grazer necessarily so limited in what it can eat (see generalist and specialist species).

The word "graze" derives from the Old English (OE) "grasian", "graze", itself related to OE "graes", "grass". For terrestrial animals grazing is normally distinguished from "browsing" in that grazing is eating grass or other low vegetation, and browsing is eating woody twigs and leaves from trees and shrubs ["Concise Oxford Dictionary", 1976 (6th ed) ISBN 0-19-861122-6. "Graze, verb: 2. Eat growing grass." "Browse, verb: 1. Feed on, crop, (leaves, twigs, scanty vegetation)."] . However, "grazing" is sometimes used to refer to both grazing and browsingfact|date=November 2007.

Grazing may be associated with mammals feeding on grasslands, or more specifically livestock on a farm. However, ecologists sometimes use the word in a much broader sense, including any organism that feeds on any other without living in close association with it or ending its life by the act of feeding on it, as described above.Begon, M., Townsend, C., Harper, J. (1996) "Ecology" (Third edition) Blackwell Science, London] An example of a grazer that might seem counterintuitive to the everyday use of the word is a mosquito, which is not a parasite in that it does not form any lasting association with its prey, and is not a true predator in that it does not kill them by this act (although they can act as a vector for fatal diseases such as malaria). In this sense it is the antithesis of parasitoidism, in which an organism (typically the larval stage of a wasp) feeds on another by eating it from within. In that case, the prey is inevitably killed by successful predation, and has an intimate association with its predator, such that its premature death would also see the parasitoid die as well. Use of the term varies however, for example a marine biologist may describe herbivorous sea urchins that feed on kelp as grazers even when they consistently kill the organism by cutting the plant down at the base.

Many smaller, selective herbivores follow grazers because they skim off the highest, tough growth of plants exposing tender shoots.Fact|date=July 2007

ee also

* Commons
* Grazing rights
* Managed intensive grazing
* Overgrazing
* Pasture
* Society for Range Management

References

[http://naturalengland.communisis.com/NaturalEnglandShop/product.aspx?ProductID=d7615a57-c014-40da-b5f8-a1c328aada56 3. Lowland Grassland Management Handbook, chapter 5]


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Look at other dictionaries:

  • Grazing — Graz ing, n. 1. The act of one who, or that which, grazes. [1913 Webster] 2. A pasture; growing grass. [1913 Webster] …   The Collaborative International Dictionary of English

  • grazing — ► NOUN ▪ grassland suitable for use as pasture …   English terms dictionary

  • grazing — [grā′ziŋ] n. 1. land to graze on; pasture 2. Informal the eating of snacks all day long or the eating of small portions of different foods …   English World dictionary

  • grazing — pp. Eating a number of small meals throughout the day; eating a selection of appetizers as your main meal. graze v. grazer n. Example Citations: Grazing was the way our body was designed to eat, says nutritionist Antony Haynes. Large meals burden …   New words

  • grazing — [[t]gre͟ɪzɪŋ[/t]] N UNCOUNT Grazing or grazing land is land on which animals graze. He had nearly a thousand acres of grazing and arable land …   English dictionary

  • Grazing — Graze Graze (gr[=a]z), v. t. [imp. & p. p. {Grazed} (gr[=a]zd); p. pr. & vb. n. {Grazing}.] [OE. grasen, AS. grasian, fr. gr[ae]s grass. See {Grass}.] 1. To feed or supply (cattle, sheep, etc.) with grass; to furnish pasture for. [1913 Webster] A …   The Collaborative International Dictionary of English

  • grazing — n. pastureland, pasture, field or plot of ground where livestock are grazed greɪz n. instance of rubbing lightly against something; scrape; scratch; act of grazing, act of eating grass v. rub lightly against something; scrape the skin from; feed …   English contemporary dictionary

  • grazing — noun Date: 1517 herbage or land for grazing …   New Collegiate Dictionary

  • grazing — noun Grazing is used before these nouns: ↑land, ↑marsh, ↑right …   Collocations dictionary

  • Grazing In The Grass — «Grazing In The Grass» Sencillo de Hugh Masekela del álbum The Promise of a Future Publicación Mayo de 1968 Formato Vinyl, 7 , 45 RPM, LP[1] …   Wikipedia Español

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