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Grazing Animals as Weed Control Agents

Published online by Cambridge University Press:  12 June 2017

Ian Popay  and
Roger Field
Ian Popay
Affiliation:
AgResearch Corporate Office, Private Bag 1135, Hamilton, New Zealand
Roger Field
Affiliation:
Plant Sci. Dep., Lincoln Univ., Lincoln, Canterbury, New Zealand
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Abstract

Literature on the effectiveness of grazing animals (especially cattle, goats, and sheep) in controlling weeds is reviewed. Availability of animals and the ability to fence them onto or off weed infestations are essential. Weeds of pastures are the most suitable subjects for control, although weeds of arable crops, forestry, and waste places are sometimes amenable to control by grazing animals. Although grazing animals themselves often cause weed problems in pasture, adjusting grazing timing or intensity or both can sometimes redress the balance. Increasing sheep or cattle stocking rates prevents animals from grazing selectively and can help control some weeds. Adjusting grazing pressure can also improve the growth of desirable pasture species so that these are more competitive and able to resist invasion of annual or biennial weeds. Introducing a different class of stock, like sheep into a cattle system or goats into a sheep system can control many weeds. Goats are capable of browsing on and controlling spiny or poisonous brush weeds, including gorse and poison ivy, without suffering adverse effects. Examples are given of the use of grazing animals for weed control in crops and forestry.

Keywords

Gorse, Ulex europaeus L. #3 ULEEUcattle, Bos tauntsgoats, Capra hircussheep, Ovis ariesNon-chemical weed controlintegrated weed managementlow input sustainable agricultureAgropyron cristatumAllium sativumAlnus rubraCarduus nutansC. pycnocephalusC. tenuiflorusCarthamus lanatusthistlesT. vermixTrifolium repensT. subterraneumZea maysCARLACENSOCIRARCIRPACIRVUCRUNUCRUPYCYPROECHPLEPHESHORLEHORMCHORMULOLRISTDTRSENJASILMATOXDITOXVX
Type
Review
Information
Weed Technology , Volume 10 , Issue 1 , March 1996 , pp. 217 - 231
Copyright
Copyright © 1996 by the Weed Science Society of America 

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