Outbreak patterns of the spruce budworm and their impacts in Canada

Abstract

Historical records of spruce budworm defoliation in Canada were analyzed to estimate variability in the spatial and temporal patterns of defoliation, and to determine 27 representative patterns that adequately describe the spatial and temporal variability in defoliation. Spatially referenced estimates of growth loss and mortality resulting from an outbreak of spruce budworm were obtained by subjecting a national forest inventory to the spatially defined representative patterns of defoliation. The use of these estimates in determining the status of Canada's forests as a carbon source or sink is discussed.

Cross‐scale effects of spruce budworm outbreaks on boreal warblers in eastern Canada

“…At a broader scale, the stratum‐level budworm variable was calculated for each year‐ t , as the average, across the previous 4 years, of the proportion of the forested area of each stratum‐ i that was affected by moderate or severe defoliation ($b_{2_{i,t}}=\sum _{y=1}^4{b}_{2_{i,t-x}}/4$). A 4‐year lag was chosen because local responses to budworm by warblers can continue over 4–5 years (Venier et al., 2009), and the effect of prolonged defoliation on forest health relates to the defoliation over the last 4–5 years (Erdle & MacLean, 1999; Gray & MacKinnon, 2006; MacLean, 2016). …”

The economics of carbon sequestration through pest management: application to forested landbases in New Brunswick and Saskatchewan, Canada

“…Bt application) activities implemented. 3 We considered both moderate and severe SBW outbreaks for each landbase, based on past outbreak cycles in New Brunswick (Royama, 1984;Steinman and MacLean, 1994), Nova Scotia (MacLean and Ostaff, 1989;Ostaff and MacLean, 1995), and Saskatchewan (Gray and MacKinnon, 2006). 4 The carbon emissions that resulted from these unprotected SBW outbreaks would thus constitute the baselines to which carbon removals from pest management activities would be compared.…”

Dynamique spatio-temporelle des épidémies de la tordeuse des bourgeons de l'épinette dans la pessière à mousses au cours XXième siècle /

“…Il semble au contraire que la dynamique d'émergence soit propre à la pessière à mousses. On sait par ailleurs que la partie au nord de la pessière à mousses est caractérisée par des volumes de sapins et d'épinettes supérieurs à 80 m3/ha et que la partie à l'est concentre les plus grosses proportions de sapins (de 20 à 40%) (Gray et MacKinnon, 2006). De plus, ces peuplements forment de vastes ensembles de résineux matures (Direction de l'aménagement des forêts, 1982).…”