Polish larch trees are among the most valuable among forest species both in natural growing conditions and in the conditions of introduction. However, its taxonomic status is not fully resolved due to the similarity in morphological features with European and Siberian larch. We conducted a comparative analysis of these species of larch on the morphological features of cones and needles. The studies were carried out in the conditions of introduction in the center of the European part of Russia. We present the average value of the trait (XSR ± Sx) and the degree of its variation (V %). The reliability of the difference between the samples according to these characteristics was determined based on the calculation of the student's criterion t. As a result, we found that the Polish larch has smaller cones and significantly differs from the European and Siberian larch in all studied features (length of cones, width of cones, number of scales in cones, length of needles). These results indicate the isolation of the Polish larch, but this pattern can be expressed not only when referring to the Polish larch in the rank of an independent species – Larix polonica Racib., but also as a subspecies of European larch (Larix decidua var. polonica (Racib. ex Wóycicki) Ostenf. & Syrach).

No abstract

The article presents the results of the first stage of investigation, aimed at improving the efficiency of the system for forest protection from fire by improving the organization and works to extinguish forest fires due to the optimal use of the dark conditions, increasing the safety of workers of forest fire groups in difficult conditions. The possibility of increasing the impact degree on the border of an existing forest fire with available forces and tools on the first day is equivalent to gaining an increase in the amount of labor hours spent within one operational period. It is comparable to the positive effect of using additional forces for a short period of time. The article presents the results of the first stage of the study. The analysis results of the state in the practice of extinguishing forest fires t dark conditions are presented. In analysis, the attention is focused on the peculiarities of the extinguishing forest fires in difficult conditions, taking into account the influence of the main regulatory factors such as limited visibility, terrain, types of plantings and ground cover, weather conditions, tools and fire extinguishing equipment used, tactical techniques and fire extinguishing methods, equipment firefighting units by individual and group protection tools, application of standard procedures for controlling forces and equipment in a fire, presence of hazardous working conditions, compliance the regulations of the existing law. In the course of the analysis, domestic and foreign experience of extinguishing forest fires at dark conditions was considered. A field research program for the next phase has been organized.

No abstract