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

Journal Article · · Canadian Journal of Forest Research
 [1];  [1];  [1];  [2];  [2];  [3]
  1. Department of Natural Resources and the Environment & Center for Environmental Sciences and Engineering, University of Connecticut, Storrs, CT, USA.
  2. Department of Biology, Virginia Commonwealth University, Richmond, VA, USA.
  3. Department of Forestry and Natural Resources and Environmental and Ecological Engineering, Purdue University, West Lafayette, IN, USA.

Canopy defoliation is an important source of disturbance in forest ecosystems that has rarely been represented in large-scale manipulation experiments. Scalable crown to canopy level experimental defoliation is needed to disentangle the 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 or trees, and completed within a timeframe of hours or days. Pressure washing proved successful at producing consistent leaf-level and whole-canopy defoliation, with 10%–20% reduction in leaf area index and consistent leaf surface area removal across branches and species. This method allows for stand-scale experimentation on defoliation disturbance in forested ecosystems and has the potential for broad application. Studies utilizing this standardized method could promote mechanistic understanding of defoliation effects on ecosystem structure and function and development of synthetic understanding across forest types, ecoregions, and defoliation sources.

Research Organization:
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). AmeriFlux
Sponsoring Organization:
USDOE
DOE Contract Number:
AC02-05CH11231
OSTI ID:
1982998
Journal Information:
Canadian Journal of Forest Research, Vol. 52, Issue 2; ISSN 0045-5067
Publisher:
Canadian Science Publishing
Country of Publication:
United States
Language:
English

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