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?