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Grazing for Cheatgrass Management Willow Hibbs Habitat Extension Biologist Natural Resources Conservation Service Wyoming Game & Fish Dept.


Ecosystem Controls Time

Climate Ecosystem Processes

Potential Biota

Topography Parent Material


Ecosystem Processes  Defoliation  Life Strategy  Resource Acquisition

Managers can use strategies and tools to influence ecosystem processes

Grazing management


Grazing Cheatgrass?

U.S. Department of the Interior, U.S. Geological Survey This page is http://gec.cr.usgs.gov/info/sw/interact/invasives_measuring.html


Natives Cheatgrass

0-50cm 50+ cm

Uneven soil moisture profile

Even soil moisture profile


Grazing Cheatgrass?

U.S. Department of the Interior, U.S. Geological Survey This page is http://gec.cr.usgs.gov/info/sw/interact/invasives_measuring.html


Grazing Management


Grass Growth •Initiated from growth points •Apical •Secondary •Axillary •3 main phases •Vegetative •Transition •Reproductive


Grass Growth: Vegetative Phase You need leaves to grow leaves!

http://www.fsl.orst.edu/forages/projects/regrowth/print-section.cfm?title=Developmental%20Phases


http://www.fsl.orst.edu/forages/projects/regrowth/print-section.cfm?title=Developmental%20Phases


Grass Growth: Transition Phase

http://www.fsl.orst.edu/forages/projects/regrowth/print-section.cfm?title=Developmental%20Phases


http://www.noble.org/ag/forage/grassmechanics101/index.htm


Grass Growth: Reproductive Phase

http://www.fsl.orst.edu/forages/projects/regrowth/print-section.cfm?title=Developmental%20Phases


http://www.caf.wvu.edu/~forage/growth.htm


% available carbohydrates in roots and crown

Carbohydrate Reserves

http://www.ext.colostate.edu/pubs/natres/06108.html


http://www.agron.iastate.edu/moore/434/grass.html


Ecological Sites


Key Points  Questionable benefits to targeted cheatgrass

grazing  Increases pressure on natives  Uneven soil moisture profile already exists  Proper grazing management is key to a

resistant, resilient system


Key Points  Grass stages  Vegetative : resilient, but leave adequate

leaf area

 Transition to boot stage: sensitive  After Reproductive: can graze, allow time

for carbohydrate reserves to replenish after


Key Points  Growth has priority over carbohydrate

storage  Carbohydrate storage increases when: - Leaf area is large - Growth rate is slow  Carbohydrate storage decreases when: - Leaf area is small - Growth rate is fast


Key Points  Leave residual cover  Cool versus warm season grasses  Ecological sites


Questions?


Grazing for Cheatgrass Management