Spatial and Time Dynamics of Pine Web Spinning Sawfly Outbreaks

Based on the materials of the state forest pathology monitoring for 1995–2024, the long-term dynamics of the areas of the star sawfly-weaver (Acantholyda posticalis Mats.) and their occurrence in 16 regions of the Russian Federation have been analyzed. Using literary data, changes in the distribution of its mass reproduction sites over the past 60 years have been identified. The largest annual areas of outbreaks were recorded in the pine forests of the Chelyabinsk (21,067 ha), Vladimir (17,737 ha), and Tver (11,180 ha) regions. Moreover, in the last two regions, as well as in the forests of the Bryansk, Oryol, Tyumen regions, and the Republic of Mari El, outbreaks of the starshaped sawfly-weaver were not observed before 1960. The presence and periodicity of outbreaks, as well as the steady trend of increasing the areas of mass reproduction in the Orenburg region, have been established and evaluated.