Forest Investment Account (FIA) - Forest Science Program
FIA Project Y051223

    Impacts of Armillaria root disease on stand productivity in the southern interior: final Technical Report for the BC FIA Forest Sciences Program
Imprint: Victoria, B.C. : Ministry of Forests. Forest Science Program, 2005
Subject: Forest Investment Account (FIA), British Columbia
Series: Forest Investment Account (FIA) - Forest Science Program
Armillaria ostoyae (Romagn.) Herink causes Armillaria root disease (DRA) of conifers and has a circumpolar distribution in the northern hemisphere (Watling et al. 1991), including the southern one-third of British Columbia (BC) (Morrison et al. 1985). In the southern interior, the disease is found in the IDF, MS, SBS, ICH and ESSF (lower elevations) biogeoclimatic (BEC) zones (Morrison et al. 1992). The fungus is a normal component of the flora on (nearly all) sites in those BEC zones, with incidence of diseased trees in mature stands ranging from 10% in the IDF to 80% in the ICH (Morrison et al. 2001). After harvest, stumps of infected trees are colonized by the fungus and become inoculum. Infection of plantation trees begins about age 6 in the ICH, with incidence of diseased trees increasing gradually until it is 30-35% at age 20 (Morrison et al. 2000). The fungus has a very broad host range, including all species of trees and many shrubs. Damage occurs throughout the rotation and is caused as growth loss in trees with non-lethal disease and mortality at a rate up to 2% per annum. Pre-commercial and commercial thinning and selective cutting increase the incidence of trees with DRA by increasing the amount of fungal inoculum (Cruickshank et al. 1997, Morrison et al. 2001). Use of these practices, especially selective cutting, is increasing in the southern interior, and their use increases the incidence of mortality and living, DRA-diseased trees. The primary objective of this ongoing project is to quantify the growth loss attributable to sub-lethal Armillaria infection in Douglas-fir plantations in the southern interior.
Related projects:  FSP_Y062223


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Updated August 16, 2010 

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