Bulkley Valley Research Centre - Science in the Public Interest

Year 2 - Development of a Spatially-Explicit Crown Allometry Model: Crown Shyness

Project Reference Number: 2008-10

Project Status: Complete

Led by: Dave Coates, PhD, Research Silviculturist, Ministry of Forests, Lands and Natural Resources, Smithers

Aaron Trowbridge, Bulkley Valley Research Centre, Smithers; Hilary Thorpe, PhD, Queen Charlotte Islands

Funder: Forest Investment Account - Forest Science Program

Project Proposal

The primary objective of this project is to develop and parameterize a distance-dependent crown allometry function for the growth model SORTIE-ND. Previous model evaluation projects have pinpointed crown allometry as an important topic for model development. In SORTIE-ND, accurate crown allometry is necessary for unbiased prediction of understory light availability which in turn is critical for understory tree growth and mortality in complex stands. Our current forest management paradigm calls for increased focus on complex stand management. To evaluate complex stand management strategies, forest managers require models that can predict growth and stand dynamics for complex stands. SORTIE-ND was designed to predict growth and stand dynamics in complex stands and we expect that a better crown model will improve the models predictive ability.

Current Year Objectives:

  • To measure crown allometry and crown shyness in existing stem-mapped stands.
  • To develop spatial and non-spatial models of crown allometry and crown shyness.

Related Reports

Publication Date Report Title Authors
January 2010 Competition and tree crowns: A neighborhood analysis of three boreal tree species Hilary Thorpe, Rasmus Astrup, Aaron Trowbridge, Dave Coates
March 2009 Development of a spatially explicit crown model Hilary Thorpe, Dave Coates, Rasmus Astrup