Ecological Characteristics of the Siberian Silk Moth (Dendrolimus sibiricus) (Insecta, Lasiocampidae) Habitat in the Altai–Sayan Mountain–Boreal Coniferous Forests Region

This article is concerned with a recent problem of an outbreak of the Siberian silk moth (Dendrolimus sibiricus Tschetverikov, 1908). This study is focused on advancement of a system of forest pathology monitoring through determination of tolerance for the harmful phytophage by forest plots. The results of this analysis are reported with respect to suitable habitats for the vital activity of the Siberian silk moth at the early phases and during the outbreak period in the conditions of mountain–southern boreal dark coniferous forest stands (phytocenoses) in Krasnoyarsk krai. This study employs data on remote sensing documents combined with the results of field survey of damaged plots together with populational characteristics of the phytophage. The habitat description is based on the forest type and silvicultural–mensuration parameters of forest stands. As a result of the analysis of ecological conditions for pest propagation, the forest stands are differentiated based on their tolerance for phytophage exposure. The first-order reservations (areas of maximum sustained numbers between outbreaks) are the Bryidae (green-moss) group of forest types; second-order, the grass group of forest types; and third-order, moist habitats in low topographic relief (riverine “near a brook” and herb–swamp forest type). The dynamics of the Siberian silk moth density is determined depending on the structural characteristics of tree stands. The results allow for territorial tracking of the dynamics and tolerance of forest plots susceptible to phytophage exposure.