README File





1. Dataset Title: Pando Aspen 2021 Remeasure




2. Name and contact information of PI: Paul C. Rogers


a. Name (same)


b. Institution Western Aspen Alliance, Utah State University


c. Address 5215 Old Main Hill


d. Email p.rogers@usu.edu


e. ORCiD ID: 0000-0001-5978-8910





6. Funding source: This study was funding by EJF Philanthropies, Western Aspen Alliance, and a US DOI Bureau of Land Management grant (L21AC10369).  




7. Project summary, description or abstract: Upland aspen (Populus spp.) forests contribute significantly to biodiversity in their circumboreal role as keystone species.  The 43-hectare Pando aspen (Populus tremuloides Michx.) clone in Utah, USA, is thought to be the largest living organism on earth, but is faltering due to chronic herbivory.  Long-term resilience in aspen communities, including Pando, rests on successful recruitment of vegetative suckers. This is the first trend assessment of this threatened iconic forest using a vital indicators approach.  I examined 64 plots using 19 indicators to determine current conditions.  Findings show that a genetically uniform Pando is 'breaking up' because of herbivory fencing.  Initial successes are tempered by nearly half of Pando that remains unprotected from chronic wild and domestic ungulates herbivory.  I propose a strategy of process-based stewardship informed by adaptive monitoring to restore the famed 'one-tree forest.'  Lessons from Pando include linkages to embattled biodiverse aspen systems facing similar challenges globally.




8. Brief description of collection and processing of data: The data consists of location, mensuration, regeneration/recruitment, and animal browse/scat data from the Pando aspen clone near Fish Lake, Utah.  This is a full remeasurement of this famous grove.  Previous full or partial measures of Pando were conducted in 2014-2016, 2017.




9. Description of files (names, or if too numerous, number of files, file type(s):


One file: PandoAspenPlotData_2021remeasure

Type: spreadsheet, in XSLX and CSV formats





10. Definition of acronyms, codes, and abbreviations:



A. Plot#: unique number for each plot; 64 plots total (dropped plot #215 due to relocation problem)


B. UTM_E: Universal Transverse Mercator easting


C. UTM_N: Universal Transverse Mercator northing


D. Elev: Elevation above sea level in meters


E. #layers: Visual estimate of distinct vertical layers of aspen over 1 ha


F. Stand cond: Qualitative (visual) overall rating of stand condition using three criterial: #layers,


disease/mortality, and browse level (detailed: Rogers, P. C., and C. M. Mittanck. 2014. Herbivory strains resilience in drought-prone aspen landscapes of the western United States. Journal of Vegetation Science 25:457-469.)


G. Treatment: 1-10 based on different land management and experimental treatments groups:


1. Outside fence


2. Inside fence, no treatment


3. Treatment (fire) control


4. Treatment (juniper removal) control


5. Treatment (selective cut) control


6. Treatment fire


7. Treatment juniper removal


8. Treatment selective cut


9. Inside 2014 fence (uphill of highway), no treatment 


10. Inside 2014 AND 1992 fence, old clear cut, dense saplings


H. Protection: none = 1; 2013 fence = 2; 2014 fence = 3


I. Common Juniper Cover: percent cover of common juniper (transect method)


J. Aspen Cover: percent cover of aspen (visual overhead method)


K. Regen count: Regeneration count; raw count of regeneration (< 2 m ht.) within two 30 x 2 m transects


L. Regen/ha: Regeneration per ha; multiply Regen count by expansion factor (83.33)


M. Regen Browse%: Percent of Regen count browsed by ungulates


N. Recruit count: Recruitment count; raw count of recruitment (> 2 m ht., < 8 cm dbh) within two 30 x 2 m transects


O. Recruit/ha: Recruitment per ha; multiply Recruit count by expansion factor (83.33) 


P. Recruit/% tph: Recruitment as a percent of trees per ha; ratio of recruitment count to Tree count


Q. Tree count: number of live and dead mature trees per ha


R. tph – tree per hectare; multiple Tree count by expansion factor (83.33)


S. Live tree count: Tree count minus standing dead trees


T. live tph: live trees per ha; multiple Live tree count by expansion factor (83.33)


U. live BA: live basal area; compute basal area based on mean range of tree diameter classes (class 8-15 cm = 11.5 cm; class >15-25 = 20 cm; class >25 = 30 cm)


V. dead BA - dead basal area; compute basal area based on mean range of tree diameter classes (class 8-15 cm = 11.5 cm; class >15-25 = 20 cm; class >25 = 30 cm)


W. dead BA as % of Total BA: dead basal area as a percent of total basal area


X. total BA: total basal area; add live and dead basal area


Y. Cattle scat/ha: count of cattle scat within transects multiplied by expansion factor (83.33)


Z. Deer scat/ha: count of deer scat (pellet groups) within transects multiplied by expansion factor (83.33)


11.  Description or definition any other unique information that would help others use your data:


12. Descriptions of parameters/variables


a. Temporal (beginning and end dates of data collection: June 1-30, 2021


b. Instruments used and units of measurements: all units metric


c. Column headings of data files (for tabular data): (see above)


d. Location/GIS Coverage (if applicable to data): UTM 434701 E, 4264266 N


e. Symbol used for missing data: blank cell


13. Special software required to use data: NA


14. Publications that cite or use this data: 


15. Was data derived from another data source?  If so, what source? NA





OPTIONAL Fields








1. Information about other files (names, locations) and documents (such as field notes, publications,etc.) that would be helpful to a person using your data:

Rogers, P. C., and C. M. Mittanck. 2014. Herbivory strains resilience in drought-prone aspen landscapes of the western United States. Journal of Vegetation Science 25:457-469