The nun moth (Lymantria monacha) is widespread throughout Eurasia and frequently experiences outbreaks. Significant increases in L. monacha numbers were repeatedly recorded in the Leningrad Oblast and adjacent regions until the mid-20th century. No outbreaks of this pest have occurred in subsequent years. In contrast, increasing population density has been observed in Scandinavian countries and Estonia. To assess the spread of L. monacha, moths were collected in 2023 and 2024 in St. Petersburg, the Leningrad Oblast, and the northern parts of the Pskov and Novgorod oblasts. Unitrap and pheromones produced in Russia (VNIIKR) and USA were used. Species identification was determined using genitalia. The highest capture rates were observed in 2023, as two pheromones were used simultaneously—those of the nun moth and the spongy moth. In 2024, only one pheromone was used one targeting the spongy moth. The number of L. monacha collected was approximately half that. A total of approximately 1500 specimens, exclusively males, were collected. The most intense flight of moths occurred in the third ten-day period of July. Traps located in or near pine forests was caught the largest number of individuals: 150 or more per trap in the northern part of the Leningrad Region (Karelian Isthmus); 85 in the Pskov Region. Overall, population density is relatively low; low-density pine forests support a stable population of nun moths.
The quality of forest reproductive material is crucial for successful reforestation and afforestation. While physical seed properties like mass are known indicators of quality, the potential of non-destructive, rapid color analysis for predicting germination in coniferous species requires further exploration. This study investigates the relationship between the seed coat color of individual Pinus sylvestris seeds, quantified in RGB (Red, Green, Blue) space using a flatbed scanner, and their subsequent germination in container nurseries. The resulting images were processed using ImageJ software to measure the mean pixel intensity (0–255) for the Red (R), Green (G), and Blue (B) channels from the segmented seed area, following the «seed–culture» passport methodology [Forestry Engineering Journal 14 | 55 (2024), 37–60]. From a population of individually tracked seeds, we compared the RGB values of germinated (N = 942) and non-germinated (N = 258) seeds after 30 days. Results from the Kolmogorov-Smirnov test showed that non-germinated seeds had significantly lower individual mass (p = 0.0045) and significantly higher pixel brightness values in the R-, G-, and B-channels (p < 0.0001) compared to germinated seeds. Normalized RGB indices also showed significant differences between groups. Our findings demonstrate that seeds with a lighter, more reflective epidermis – indicative of higher RGB brightness – are statistically associated with a lower probability of successful germination under container nursery conditions. This non-destructive, low-cost method shows significant promise for the rapid pre-sorting of Scots pine seeds. It offers a practical tool to improve the efficiency and predictability of seedling production in forest nurseries by increasing the proportion of viable seeds in sowing batches.
The previously unknown compounds—3-(dichloromethyl)-2-nitro-6,7-dihydro-1-benzofuran-4(5H)-ones—have been synthesized and structurally characterized via single-crystal X-ray diffraction, 1H, 13C–{1H}, 1H–13C HMQC and 1H–13C HMBC NMR spectroscopy, IR, and UV spectroscopy.
In view of global climate change and biodiversity decline, long-term research in primeval forests escaped from timber harvesting is especially important. We aimed at analysing the dynamics of number and volume of standing dead trees (snags), as well as the patterns of tree mortality and the longevity of snags in primeval middle-boreal spruce stands. The study is based on the database of tree stand inventories performed on the eleven permanent sample plots (SPs) for 25–46 years. The volume of snags during the period from 1971 to 2019 varied from 0.4 to 164 m3 ha–1, with an average annual turnover rate (the period from the tree death to snag fall) from 0.07 to 32.7 m3 ha–1 year–1. In several biogeocoenoses, the peaks in tree mortality through decline after windthrows were observed, resulting in the stock of coarse woody debris being comparable to the stock of a forest stand. The rate and the mode of tree mortality, and the species distribution of snags, depend on the soil moisture regime, tree species composition and age structure of the forest stand. Before death, some trees were weakened for a period up to 46 years. The time of tree weakening before death (the period from the moment when mechanical damage, traces of insect activity, diseases, etc. were noted in the tree, until the moment when a tree died) did not have a significant effect on the duration of snag longevity. The duration of snag longevity varies from 2 to 30 or more years, depending on interrelated factors such as tree species and size, moisture conditions, tree species composition of forest stand, and the successional status of the biogeocoenosis.
Reactions of β-CCl 3 -β-hydroxy ketones or β-CCl 3 -enones with various nucleophiles (nitriles, arenes, and hydride ions) in triflic acid CF 3 SO 3 H (TfOH) afford various CCl 3 -substituted compounds, including amides, ketones, and indenes.
