GIS-based prediction of the foliage browsing insects' outbreaks in the pine stands of the SE "Kreminske FHE"

To improve the detection and prevention of foliage browsing insects' outbreaks it is very important to reveal the forest plots, which are the most favorable for these pests. The aim of this research was to predict using GIS technologies the spatial dynamics of foliage browsing insects' outbreaks in the pine stands of the State Enterprise "Kreminske FHE" (Luhansk region). Forest inventory databases of Production Association "Ukrderzhlisproekt" were analyzed for the SE "Kreminske FHE" as of 2001 and 2011. Rating of forest plots preferences for common pine sawfly (Diprion pini L.) and European pine sawfly (Neodiprion sertifer Geoffr.) considered the type of forest site conditions, age of stand, density of stocking, and the part of pine in the stand composition. If forest plot bordered with clear-cut, then 1 point was added to the general score of the threat. It was shown, that the area with high threat of European pine sawfly and common pine sawfly outbreaks for 2001–2011 increased in the forest fund of the SE "Kreminske FHE" by 702.8 and 2004.2 hectares respectively. The part of foci area made up 27.5 and 32 % from forest fund area, 42.5 % and 49.5 % from pine stands area for European pine sawfly and common pine sawfly respectively. The areas of pine sawflies foci increased mainly in result of decrease the stocking density of pine stands and increase the number of plots which border with clear-cuts. The survey for pine sawflies is recommended to carry out first of all in the plots with high threat of foci appearance.