Biennial aerial application of Bacillus thuringiensis Berliner var. kurstaki is the most cost-effective approach of protection against spruce budworm (Choristoneura fumiferana [Clemens])

The main goal of this study is to evaluate the efficacy of different protection scenarios in reducing tree mortality and growth losses over a 11-year period (2010-2020) in mixed fir-spruce stands that are dominated by mature balsam fir trees. We hypothesize that a less-intensive protection approach (Btk applications every 2 years) may provide a level of protection similar to the standard program currently used in the Province of Quebec. In 2007, we established nineteen 100-ha experimental units in Quebec’s Côte-Nord region to determine the efficacy of different Btk spraying scenarios for reducing tree mortality and volume losses in mixed stands of balsam fir (Abies balsamea [L.] Mill.), white spruce (Picea glauca [Moench] Voss) and black spruce (P. mariana [Mill.] BSP). Tree mortality was monitored annually in three circular plots of 400 m2 within each experimental unit. Growth losses were evaluated using stem analyses. This dataset contains the rawdata used in the related paper publish in Annals of Forest Science. The variables included in the dataset are tree mortality, annual volume increment (AVI), specific volume increment (SVI), and defoliation by host species and year since the first aerial application of Btk in the experimental unit.