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Does size matter? Animal units and animal unit months


Lamar Smith
Joe Hicks
Scott Lusk
Mike Hemmovich
Shane Green
Sarah McCord
Mike Pellant
Judith Dyess
Jim Sprinkle
Amanda Gearhart
Sherm Karl
Mike Hannemann
Ken Spaeth
Jason Karl
Dave Pyke
Jordan Spaak
Andrew Brischke
Del Despain
Matt Phillippi
Dave Weixelmann
Alan Bass
Jessie Page
Lori Metz
David Toledo
Emily Kachergis



Publication type:

Scientific Journal (JRNL)

Primary Station(s):

Rocky Mountain Research Station


Rangelands. 39(1): 17-19.


The concepts of animal units, animal unit months, and animal unit equivalents have long been used as standards for range management planning, estimating stocking rates, reporting actual use, assessing grazing fees, ranch appraisal, and other purposes. Increasing size of cattle on rangelands has led some to suggest that the definition of animal units and animal unit months requires revision. Range managers need to understand these concepts and arbitrarily changing them would lead to confusion. The Rangeland Assessment and Monitoring Committee reviewed this issue and concluded that the existing definitions are adequate to accommodate increasing size of cattle.


Smith, Lamar; Hicks, Joe; Lusk, Scott; Hemmovich, Mike; Green, Shane; McCord, Sarah; Pellant, Mike; Mitchell, John; Dyess, Judith; Sprinkle, Jim; Gearhart, Amanda; Karl, Sherm; Hannemann, Mike; Spaeth, Ken; Karl, Jason; Reeves, Matt; Pyke, Dave; Spaak, Jordan; Brischke, Andrew; Despain, Del; Phillippi, Matt; Weixelmann, Dave; Bass, Alan; Page, Jessie; Metz, Lori; Toledo, David; Kachergis, Emily. 2017. Does size matter? Animal units and animal unit months. Rangelands. 39(1): 17-19.


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