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An experimental approach for crown to whole-canopy defoliation in forests

Informally Refereed
Authors: Robert Fahey, Danielle Tanzer, Brandon Alveshere, Jeff Atkins, Christopher Gough, Brady Harfiman
Year: 2022
Type: Scientific Journal
Station: Southern Research Station


canopy defoliation is an important source of disturbance in forest ecosystems that has rarely beenrepresented in large-scale manipulation experiments. Scalable crown to canopy level experimentaldefoliation is needed to disentangle effects of variable intensity, timing, and frequency on forest structure,function, and mortality. We present a novel pressure washing-based defoliation method that can be implemented at the canopy-scale, throughout the canopy volume, targeted to individual leaves/trees, andcompleted within a timeframe of hours/days. Pressure washing proved successful at producing consistentleaf-level and whole-canopy defoliation with 10-20% reduction in leaf area index and consistent leafsurface area removal across branches and species. This method allows for stand-scale experimentation ondefoliation disturbance in forested ecosystems and has the potential for broad application. Studiesutilizing this standardized method could promote mechanistic understanding of defoliation effects o ecosystem structure and function and development of synthetic understanding across forest types,ecoregions, and defoliation sources.


defoliation, experiment, herbivory, canopy, disturbance


Fahey, Robert; Tanzer, Danielle; Alveshere, Brandon;Atkins, Jeff;Gough, Christopher;Hardiman, Brady;An experimental approach for crown to wholecanopy defoliation in forests,. 2022. 24p.