Skip to main content
U.S. flag

An official website of the United States government

SPRUCE Ground Observations of Phenology in Experimental Plots 2021


This data set consists of one comma separated (*.csv) file containing phenological transition dates, as derived from direct observations of vegetative and reproductive phenology recorded by a human observer, from the SPRUCE experiment during 2021, the sixth full year of whole-ecosystem warming (Hanson et al. 2017). Both spring and autumn phenological events are included.


Since April 2016, human observers have been directly tracking the phenology of both woody and herbaceous species on a weekly schedule within the SPRUCE experimental chambers, these data are reported in annual ground observations data sets (see Related Data Sets). The observed date reported here is the first survey date in 2021 on which an event/phenophase was definitively observed.


This data set also contains a companion file in HTML (*.html) format containing figures showing the relationship between the day of year and temperature treatment for different phenological phases by species for 2021.

User note: Phenological transition data from 2016-2021 are available. See the Related Datasets section of the user guide for more details. 


Schädel, C., K. J. Pearson, A. D. Richardson, J.M. Warren, and P. J. Hanson. 2022. SPRUCE Ground Observations of Phenology in Experimental Plots 2021. Oak Ridge National Laboratory, TES SFA, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A.




Wednesday, August 3, 2022

SPRUCE ID: spruce.099


Direct observation of phenophases.

Click image to see full-sized version

An official website of the U.S. Department of Energy and the USDA Forest Service

Looking for U.S. government information and services?