The Effect of Large Fire on Aspen Recruitment

Trent WildeUtah State University Extension

2014 Utah Section Society for Range ManagementFall Meeting

November 6, 2014Logan, Utah

Monroe Mountain Working Group

Operating Hypothesis:

“Large disturbances in seral aspen, repeated over multiple years, can overwhelm herbivory and allow stems to successfully recruit”

• How large is large enough?

Oldroyd Fire

• Monroe Mountain in South Central Utah• Burned in the summer of 2000• 1329 GIS Acres• Clone extinction

Aspen are Important

Oldroyd Fire AreaMonroe MountainPre-Fire mid 1990’s

Aspen are Important

Oldroyd Fire AreaMonroe Mountain

2011

1996 Pole Creek Fire

Pole Creek Fire

• Burned in the summer of 1996• South Central Utah• 20 miles west of Oldroyd Fire• 7113 GIS Acres

Methodology

• Working at the landscape scale• Documenting on the “patch” or “stand”

level• Correlates with work from Rocky Mountain

Research Station and Colorado Forest Restoration Institute.

• http://www.fs.fed.us/rm/pubs/rmrs_gtr310.html

GPS Aspen Patches

Aspen are ImportantLegend

NonAspenConiferVegetationPreFire1993

NotBurned

AspenRecruitment

NoAspenRecruitment

Aspen are ImportantLegend

NonAspenConiferVegetationPreFire1993

NotBurned

AspenRecruitment

NoAspenRecruitment

NonAspenConiferVegetationPreFire1993

• Pre-Fire vegetation types other than aspen and conifer as identified through aerial photos from 1993 (black and white)

• Total acreage = 2,708 acres

Aspen are ImportantLegend

NonAspenConiferVegetationPreFire1993

NotBurned

AspenRecruitment

NoAspenRecruitment

Definitions:

NotBurned

• Areas within USFS 1996 Pole Creek Fire Boundary which were not burned during fire as identified through aerial photos post-fire

• Total acreage = 1,354 acres

Aspen are ImportantLegend

NonAspenConiferVegetationPreFire1993

NotBurned

AspenRecruitment

NoAspenRecruitment

Definitions:

AspenRecruitment

• Stands of recruited aspen identified on the ground and plotted using handheld GPS (Trimble GeoXT 6000 with Floodlight tech.)

• Total acreage = 2,164 acres

Aspen are ImportantLegend

NonAspenConiferVegetationPreFire1993

NotBurned

AspenRecruitment

NoAspenRecruitment

Definitions:

NoAspenRecruitment

• Areas identified as aspen or conifer pre-fire, but where there is no aspen recruitment in 2013

• Total acreage = 887 acres

Aspen are ImportantLegend

NonAspenConiferVegetationPreFire1993

NotBurned

AspenRecruitment

NoAspenRecruitment

NoAspenRecruitment 887AspenRecruitment 2,164Potential Recruitment 3,051 acres

Aspen Recruitment 2,164 = 0.709 or 71%Potential Recruitment 3,051 Recruitment

Aspen are Important

Aspen are Important

Aspen are Important

Aspen are Important

Conclusions

1996 Pole Creek Fire (7113 GIS acres)

• 71% of potential aspen recruitment acres have aspen recruitment in 2013

• A significant correlation between fire size and percentage of aspen recruitment

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