Forest Investment Account

Abstract of FII Project R04-041

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Modeling impacts of dwarf mistletoe in coastal British Columbia western hemlock forests

Author(s): Muir, John (BC Ministry of Forests)
Subject: Forestry, Pathology, Silviculture/Forest Management Systems, Technology/GIS/Modeling/Remote Sensing
Series: Forest Investment Account (FIA) - Forest Science Program


Dwarf mistletoe, a parasitic plant, is endemic in coastal western hemlock forests. The mistletoe spreads by seeds dispersed from residual to nearby young trees. Over time, infestations significantly reduce growth of older trees, but occasionally spread appears negligible. Variable retention silviculture regimes create conditions that could exacerbate spread, intensification and impacts of mistletoe, but data to evaluate effects are lacking. We propose to use established sampling protocols to measure effects of mistletoe on wood quality and quantity of infected and uninfected trees. Significant effects and a spatial model of mistletoe spread will be incorporated in the growth model TASS and other models. These will enable projections of effects on growth of trees and stands and enable quantitative evaluations of sustainability and effectiveness of management regimes and mistletoe impacts. In future work, we will sample and model effects of other important factors such as site index and ecological subzone.

For further information, please contact John Muir, BC Ministry of Forests

Updated September 08, 2005 

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