Forest Investment Account (FIA) - Forest Science Program
FII Project R04-008

    Impacts of Armillaria root disease on stand productivity in the Southern Interior: final technical report for Forest Innovation and Investment BC
Imprint: [Victoria, B.C.] : Natural Resources Canada, Canadian Forest Service, 2004
Subject: Armillaria Root Rot, British Columbia
Series: Forest Investment Account (FIA) - Forest Science Program
The belowground incidence of trees infected with Armillaria root disease (DRA) ranged from 23-60% in Douglas-fir plantations, and 80% in one mid-rotation stand. The increase in incidence of newly infected trees peaked about age 16-20, consistent with root closure in the stand. The fungus continues to infect both within and between roots as the trees age, but symptoms are also mostly not apparent because of building host resistance as the trees age. Juvenile trees with all root lesions contained (callused) ranged from 18% to 38%. In mid-rotation trees, 52% of the trees had all lesions contained. There are still many trees with spreading lesions that probably represent new infections as the fungus repeatedly infects new areas (primarily with rhizomorphs) in the root system. Mortality is expected to stabilize somewhat between the ages of 30 and 60, but then is expected to increase after this time.
Stephen Stearns-Smith, Gordon Neinaber, Michael Cruichshank, Albert Nussbaum.


Final Project Abstract (22Kb)

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Updated August 16, 2010 

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