© 2014 Board of Regents, South Dakota State University iGrow.org
Mob Grazing: What is it all about?
Alexander “Sandy” Smart
© 2014 Board of Regents, South Dakota State University iGrow.org iGrow.org
Definition
Shared CharacteristicsHigh stocking density (25,000 to over 1
million pounds of live weight per acre)Frequent movement of livestock (Once per
day to several times per day)High trampling and/or consumption of forageHigh labor and management
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Common Objectives
Improve the land (landscaping)Vegetation and soil health
Increase harvest efficiencyCarrying capacity
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Mob Grazing Project Sites
• New Underwood• Quinn• Kadoka• Selby• Eureka• Reliance• Chamberlain• Hayti• Volga• Gary
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Stocking density
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HarvestEfficiency 33% 43% 63% 34%
Quinn Selby Chamberlain Hayti0
500
1000
1500
2000
2500
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3500
4000
4500
2014 Biomass Before and After Mob Grazing
Pre VegPost VegPre LitterPost LitterTrampled
Location
Pou
nd
s/acr
e
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Different stocking densities - Volga
50 100 200 400 8000
0.1
0.2
0.3
0.4
0.5
0.6
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1
20122013
Stocking Density (1,000 lbs/ac)
Uti
lizati
on (
%)
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2012 % Grass Cover
Mob grazing reduced grass cover by 59% whereas rotation reduced grass by 43% for sites sampled before and after both grazing systems.
Mob Rotation Mob RotationEureka Reliance
0
5
10
15
20
25
30
35
40%
Gra
ss
Mob Rotation0
5
10
15
20
25
30
35
40
45
BeforeAfter
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Before vs. After Mob GrazingJuly 11, 2012 (57,000 lbs/acre for 24 hours)
Before After
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After Mob vs. After RotationJuly 17, 2012
Mob (1,000,000 lbs/acre)for 1.3 hours
Rotation (55,000 lbs/acre)for 12 hours
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% New litter cover
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Dung density
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2012 Tour
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2013 Tour
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Videos
Pat Guptill https://www.youtube.com/watch?v=fWC9qkYdDNA
Charlie Totton https://www.youtube.com/watch?v=MJ4tlSkVxAk
Rick Smith https://www.youtube.com/watch?v=NA9D5eiLHlw
© 2014 Board of Regents, South Dakota State University iGrow.org iGrow.org
Summary
Producers are getting a higher harvest efficiency
Haven’t documented a change in productivity or soil health yet
© 2014 Board of Regents, South Dakota State University iGrow.org iGrow.org
Questions