Fig. 1: Overview of SBW outbreak progression among three forest composition types.
From: Defoliation-induced changes in foliage quality may trigger broad-scale insect outbreaks
Annual defoliation (a), larval density (b), annual litterfall (c), and cumulative tree mortality (d) with spruce budworm outbreak progression among three forest composition types. Annual defoliation and larval density were averaged from the sampled branches of host trees at the stand level. Litterfall represents the total litterfall (needle and leaf litter, SBW frass) in the 21 traps in each stand, while mortality represents the cumulative annual dead basal area of SBW hosts within each stand. Stand level values were then averaged by forest composition types.
