Distinct effects of N and P addition on soil enzyme activities and C distribution in aggregates in a subalpine spruce plantation

We assessed stream ecosystem-level response to a drought-induced defoliation event by gypsy moth caterpillars (Lymantria dispar) with high-frequency water quality sensors. The defoliation event was compared to the prior year of data. Based on long-term records of precipitation and drought indices, the drought of 2015–2016 in Rhode Island, USA was an extreme climatic event that preceded and likely precipitated the defoliation from insect infestation. Canopy cover in the riparian area was reduced by over 50% increasing light availability which warmed the stream and stimulated autotrophic activity. Frass and leaf detritus contributed particulate carbon and organic nutrients to the stream. Based on locally calibrated s::can spectro::lyser data, nitrate concentration and flux did not significantly increase during defoliation while orthophosphate concentration and flux did significantly increase during part of the defoliation period. Lower mean daily dissolved oxygen (DO) levels and wider diel cycles of DO indicated higher biological activity during the defoliation event. Stream metabolism metrics were also significantly higher during defoliation and pointed to heterotrophic activity dominating in the stream. The increases in stream metabolism were low compared to other studies; in streams with higher nutrient levels (e.g., in agricultural or urban watersheds) the increase in light and temperature could have a stronger influence on stream metabolism. The in-stream metabolic processes and nutrient fluxes observed in response to the drought-driven defoliation event resulted from the long-term deployment of high-frequency water sensors. The proliferation of these water sensors now enable studies that assess ecosystem responses to stochastic, unusual disturbances.     

Dynamics of twolined chestnut borer Agrilus bilineatus as influenced by defoliation and selection thinning

1 The twolined chestnut borer, Agrilus bilineatus (Coleoptera: Buprestidae), is a major mortality agent of stressed oak trees. However, patterns of abundance and population change are not well understood. 2 We studied the spatial and temporal variation in abundance of twolined chestnut borer adults during a gypsy moth, Lymantria dispar (Lepidoptera: Lymnatriidae), outbreak and examined the influence of both defoliation and thinning on twolined chestnut borer abundance. 3 In stands that were defoliated by gypsy moth, extensive defoliation occurred in one year, and major overstory tree mortality followed in the next. Most mortality occurred in the year preceding the peak year of twolined chestnut borer abundance and abundance of twolined chestnut borer was positively associated with defoliation and mortality in the previous year. 4 Twolined chestnut borers were more frequently associated with poor or fair crown condition trees than trees with good crown condition and were more abundant on members of the red oak group than the white oak group.     

Anthropogenic drivers of gypsy moth spread

The gypsy moth, Lymantria dispar (L.), is a polyphagous defoliator introduced to Medford, Massachusetts in 1869. It has spread to over 860,000 km² in North America, but this still only represents ¼ of its susceptible host range in the United States. To delay defoliation in the remaining susceptible host range, the government maintains a barrier zone and a quarantine, reflecting a presumption that anthropogenic factors are important in the spread of gypsy moth. We develop a model framework that relates these factors along with biophysical characteristics to a county’s susceptibility to gypsy moth invasion. We then compile a dataset for counties within 200 km of the infested area and use trap catch data from 1999 to 2007 to estimate the probability of gypsy moth presence. As expected, gypsy moth is more likely to be found close to the population front and to traps that recorded moths in the previous year. However, when controlling for these factors, our most robust finding is that the use of wood for home heating and energy is consistently positively correlated with the presence of gypsy moth. In contrast, the movement of wood products by industry, which is actively regulated by state and federal governments, is rarely correlated with the presence of gypsy moth. This is consistent with effective regulation of the movement of goods by industry, but not by the public. Our findings provide empirical support for the importance and challenge of firewood as a vector for non-native forest insects.     

Genetic determination of tannins and herbivore resistance in <Emphasis Type="Italic">Quercus ilex</Emphasis>

Genetic variability of trees influences the chemical composition of tissues. This determines herbivore impact and, consequently, herbivore performance. We evaluated the independent effects of plant genotype and provenance on the tannin content of holm oak (Quercus ilex) and their consequences for herbivory and performance of gypsy moth (Lymantria dispar) larvae. Oak seedlings of 48 open-pollinated families from six populations were grown in a common garden in central Spain. Half the plants were subjected to defoliation by gypsy moth larvae and the other half were destructively sampled for chemical analysis. Tannin content of leaves did not differ significantly among populations but differed significantly among families. Estimates of heritability (h ²) and quantitative genetic differentiation among populations for tannin content (Q _ST) were 0.83 and 0.12, respectively. Defoliation was not related to the tannin content of plants nor to spine and trichome densities of leaves, although positive family–mean associations were observed between defoliation and both seed weight and plant height (P < 0.003). Among the oak populations, differential increase in larval weight gain with defoliation was observed. Leaf tannin content in Q. ilex is genetically controlled but does not influence defoliation or predict performance of the larvae. Different efficiencies of food utilisation depending on the oak genotypes indicate that other plant traits are influencing the feeding patterns and fitness of L. dispar and consequent population dynamics.     

Phase-dependent outbreak dynamics of geometrid moth linked to host plant phenology

Climatically driven Moran effects have often been invoked as the most likely cause of regionally synchronized outbreaks of insect herbivores without identifying the exact mechanism. However, the degree of match between host plant and larval phenology is crucial for the growth and survival of many spring-feeding pest insects, suggesting that a phenological match/mismatch-driven Moran effect may act as a synchronizing agent.We analyse the phase-dependent spatial dynamics of defoliation caused by cyclically outbreaking geometrid moths in northern boreal birch forest in Fennoscandia through the most recent massive outbreak (2000–2008). We use satellite-derived time series of the prevalence of moth defoliation and the onset of the growing season for the entire region to investigate the link between the patterns of defoliation and outbreak spread. In addition, we examine whether a phase-dependent coherence in the pattern of spatial synchrony exists between defoliation and onset of the growing season, in order to evaluate if the degree of matching phenology between the moth and their host plant could be the mechanism behind a Moran effect.The strength of regional spatial synchrony in defoliation and the pattern of defoliation spread were both highly phase-dependent. The incipient phase of the outbreak was characterized by high regional synchrony in defoliation and long spread distances, compared with the epidemic and crash phase. Defoliation spread was best described using a two-scale stratified spread model, suggesting that defoliation spread is governed by two processes operating at different spatial scale. The pattern of phase-dependent spatial synchrony was coherent in both defoliation and onset of the growing season. This suggests that the timing of spring phenology plays a role in the large-scale synchronization of birch forest moth outbreaks.     

FORECASTING GYPSY MOTH DEFOLIATION WITH A GEOGRAPHICAL INFORMATION SYSTEM

Abstract In this study, we developed a series of logistic regression models for forecasting gypsy moth defoliation. The models were parameterized by using data collected over a small scaled 100m× 100m gridarea; the independent variables included egg mass density, male moth trap, previous year defoliation, and distance to the nearest cell which was defoliated in the previous year. We simulated the decision-making by using these models; this method essentially simulated the application of current gypsy moth management decision-making. The results indicated that these models can be more reliably applied to actual management decision.     

Refoliation of deciduous canopy trees following severe insect defoliation: comparison of <Emphasis Type="Italic">Fagus crenata</Emphasis> and <Emphasis Type="Italic">Quercus crispula</Emphasis>

Deciduous trees can survive severe defoliation by herbivores and often refoliate in the same season. Refoliation following severe defoliation represents compensatory regrowth to recover foliage biomass. Although the relationship between defoliation intensity and degree of refoliation at the individual level has been quantified following artificial defoliation for saplings and small trees, no study has examined the relationship for canopy trees and interspecific differences in this relationship. In this study, defoliation by gypsy moths in an outbreak year and subsequent refoliation were visually surveyed for canopy trees of Fagus crenata (n?=?80) and Quercus crispula (n?=?113) in central Japan. Defoliation and refoliation estimates were scored in 10% classes as the ratio to foliage present before defoliation. The degree of refoliation and the proportion of refoliated trees were high in severely defoliated trees. For 60 and 100% defoliated trees, respective refoliations were 2 and 66% for F. crenata, and 37 and 88% for Q. crispula. All of the 90 and 100% defoliated trees refoliated. These results indicate that severely defoliated trees show an increased need for refoliation to maintain metabolism. Beta regression analysis showed that Q. crispula possessed higher refoliation capability than F. crenata. This is likely associated with the relatively large storage reserves and recurrent growth flush pattern of oak species, which are strong characteristics of oaks and adaptive for response to herbivory and catastrophic disturbances. Interspecific differences in refoliation capability may exert differential effects on forest ecosystem processes, such as influencing the growth of understory species.     

Gypsy moth-induced growth decline of Larix sibirica in a forest-steppe ecotone

Effects of a gypsy moth attack on the productivity of Larix sibirica on tree-ring width were analyzed in a case study of a mountain site in the western Khentey in the northern Mongolian forest-steppe ecotone. A major aim of the study was to assess whether reduced productivity by gypsy moth herbivory could contribute to fluctuations of the forest edge to the steppe in larch-dominated woodlands. In the year of the infestation, larch trees at the forest edge lost 90% of their needles and latewood formation was strongly reduced. However, earlywood formation was widely completed before the gypsy moth attack and, therefore, total tree-ring width was not below the average of the five years prior to infestation. In the two years following the gypsy moth invasion, annual stem increment was strongly reduced. Trees growing 30–100 m inside the forest showed a much weaker response of tree-ring widths to the gypsy moth infestation consistent with significantly higher defoliation at forest edge than in the forest interior. Old trees exhibited a stronger growth decline than middle-aged trees, indicating higher infestation of dominant, exposed trees, which are thought to be better accessible to the wind-dispersed gypsy moth larvae hatching in the early growing season on the steppe. Under the current climate, occasional growth reductions are thought to be of little effect on the performance of L. sibirica, as fast-growing competitors of other tree species, which are not or hardly affected by gypsy moth, are absent.     

Spatial analysis of gypsy moth populations in Sardinia using geostatistical and climate models

• 1 Spatial fluctuations of the Sardinian population of the gypsy moth Lymantria dispar (L.) (Lepidoptera: Lymantriidae) were characterized using geostatistical and climate models. Data on gypsy moth egg mass abundance recorded at 282 permanent monitoring sites from 1980 to 2004 were incorporated in a geographic information system with the vegetational, geomorphological and pedological features of the sites.
• 2 Statistical analyses revealed that the relative outbreak frequency was related to the predominant host tree, slope and elevation of the monitoring sites, whereas there was no correlation between outbreak frequency and exposure and soil type.
• 3 By using bioclimatic modelling, probability maps of gypsy moth outbreaks were generated. The model identified a probability surface with climatic conditions favourable to gypsy moth outbreaks and thus potentially subject to defoliation. The maps included 92 sites where outbreaks never occurred, suggesting that the Sardinian climate may not be a determinant factor for gypsy moth outbreaks.
• 4 The geostatistical method cokriging with outbreak frequency as a covariate was found to be the most suitable technique to estimate gypsy moth egg mass abundance. Semivariograms showed spatial correlation of egg mass abundance within the range 18.5–53 km. The results obtained were used to create regional gypsy moth distribution maps by cokriging, which demonstrated the outbreak foci and different infestation levels at each monitoring area. These results can help to delimit the treatment areas and develop rational gypsy moth management programmes.

     

Pheromone‐trapping the nun moth,Lymantria monacha (Lepidoptera: Lymantriidae) in Inner Mongolia,China

The nun moth, Lymantria monacha L., is one of the most important defoliators of Eurasian coniferous forests. Outbreaks during 2011–2015 in the natural/planted larch, and larch‐birch mixed forests of the Greater Khingan Range in Inner Mongolia, China, caused tremendous timber losses from severe defoliation and tree mortality. A series of trapping experiments were conducted in these outbreak areas to evaluate the efficacy of a synthetic species‐specific pheromone lure based on the female pheromone blend of European nun moth populations. Our results clearly show that the nun moth in Inner Mongolia is highly and specifically attracted to this synthetic pheromone, with few gypsy moths (Lymantria dispar) captured. Flight activity monitoring of L. monacha male moths using pheromone‐baited Unitraps at 2 locations during the summer of 2015 indicated that the flight period started in mid‐July, peaking in early August at both locations. Based on male moth captures, there was a strong diurnal rhythm of flight activity throughout the entire scotophase, peaking between 22:00 and 24:00. Unitraps and wing traps had significantly and surprisingly higher catches than the gypsy moth traps. Unitraps fastened to tree trunks 2 m above ground caught significantly more male moths than those at the ground level or at 5 m height. Male L. monacha moths can be attracted to pheromone‐baited traps in open areas 150–200 m distant from the infested forest edge. Our data should allow improvement on the performance of pheromone‐baited traps for monitoring or mass‐trapping to combat outbreaks of this pest in northeastern China.     

Lepidoptera‐specific insecticide used to suppress gypsy moth outbreaks may benefit non‐target forest Lepidoptera

相似文献   

Incidence and ecological relationships of pupal parasitism byBrachymeria intermedia in new Jersey populations of the gypsy moth

Pupal parasitism of the gypsy moth,Lymantria dispar (L.), was monitored in 15 study plots in New Jersey from 1978 to 1988. The predominant parasitoid was a chalcidid wasp,Brachymeria intermedia (Nees), which was found in only six plots. Parasitism was generally observed in the year of or preceding the peak numbers of gypsy moth egg masses. Parasitism exceeded 4% in only one plot. Percentage parasitism was correlated significantly with numbers of egg masses per hectare in the current season and with numbers of pupae per plot in the previous season, suggesting delayed density dependence. A multiple regression analysis found percentage parasitism to be correlated significantly with percentage infection by nuclear polyhedrosis virus, density of male host pupae, and mean minimum temperature in August and March. A canonical discriminant analysis carried out to distinguish study plots with and without the parasitoid was significant. Plots withB. intermedia had relatively higher host populations and defoliation.     

Migration of the Northern Boundary of the Siberian Silk Moth

Climate changes have induced the northward migration of outbreaks of the Siberian silk moth (Dendrolimus sibiricus Tschetv.), one of the most dangerous pests in the taiga. The initial outbreak of the Siberian silk moth began in 2014 in Siberian pine.fir stands within the Yenisei Plain on the southwestern flat slopes at elevations up to 200 m above sea level. Further, the outbreak extended to the parts of the forest with higher humidity, the northern slopes, and Yenisei Ridge at low and middle elevations. The northern limit of the outbreak zone shifted to 50 km (to 60°26′ N) northward from the historical boundary of formerly observed outbreaks. The outbreak was incited by an increase in aridity, the sum of positive temperatures (t > +10°C), and a decrease in soil moisture. It extended to an area of 800000 ha. Stand mortality was accompanied by the activation of secondary pests, including aggressive bark beetle species Polygraphus proximus. The outbreak under study is part of the panzonal outbreak that occurred in 2014–2017 on the territory of Siberia in Krasnoyarsk krai and Tomsk, Kemerovo, and Irkutsk oblasts. The increase in warming, aridity, and vegetative period provides opportunities for the Siberian silk moth to migrate to the northern dark-conifer taiga.     

Induced plant defenses breached? Phytochemical induction protects an herbivore from disease

Although wound-induced responses in plants are widespread, neither the ecological nor the evolutionary significance of phytochemical induction is clear. Several studies have shown, for example, that induced responses can act against both plant pathogens and herbivores simultaneously. We present the first evidence that phytochemical induction can inhibit a pathogen of the herbivore responsible for the defoliation. In 1990, we generated leaf damage by enclosing gypsy moth larvae on branches of red oak trees. We then inoculated a second cohort of larvae with a nuclear polyhedrosis virus (LdNPV) on foliage from the damaged branches. Larvae were less susceptible to virus consumed on foliage from branches with increasing levels of defoliation, and with higher concentrations of gallotannin. Defoliation itself was not related to any of our chemistry measures. Field sampling supported the results of our experiments: death from virus among feral larvae collected from unmanipulated trees was also negatively correlated with defoliation. In 1991, defoliation and gallotannin were again found to inhibit the virus. In addition, gallotannin concentrations were found to be positively correlated with defoliation the previous year. Compared with previous results that demonstrated a delecterious effect of induction on gypsy moth pupal weight and fecundity, the inhibition of the virus should confer an advantage to the gypsy moth. Since leaf damage levels increase as gypsy moth density increases, and since leaf damage inhibits the gypsy moth virus, there is the potential for positive feedback in the system. If phytochemical induction in red oak can inhibit an animal pathogen such as LdNPV, it suggests to us that induction in red oak is a generalized response to tissue damage rather than an adaptive defense against herbivores.     

Blood Feeding Status,Gonotrophic Cycle and Survivorship of <Emphasis Type="Italic">Aedes (Stegomyia) aegypti</Emphasis> (L.) (Diptera: Culicidae) Caught in Churches from Merida,Yucatan, Mexico

Blood-feeding status, gonotrophic cycle, and survival rates of Aedes (Stegmyia) aegypti (L.) was investigated in catholic churches from Merida, Yucatan. Female Ae. aegypti were caught using backpack aspirator during 25 consecutive days in rainy (2015) and dry season (2016). Blood-feeding status was determined by external examination of the abdomen and classified as unfed, fed, and gravid. Daily changes in the parous–nulliparous ratio were recorded, and the gonotrophic cycle length was estimated by a time series analysis. Also, was observed the vitellogenesis to monitoring egg maturity. In total, 408 females Ae. aegypti were caught, and there was a significant difference in the number of females collected per season (Z = ?6.729, P ≤ 0.05). A great number was caught in the rainy season (n = 329). In the dry season, 79 females were caught, which the fed females were twice greatest than the unfed. The length of gonotrophic cycle was estimated on the base of a high correlation coefficient value appearing every 4 days in rainy at 26.7 ± 1.22°C, and 3 days in dry season at 29.8 ± 1.47°C. The daily survival rate of the Ae. aegypti population was higher in both seasons, 0.94 and 0.93 for the rainy and dry season, respectively. The minimum time estimated for developing mature eggs after blood feeding was similar in both seasons (3.5 days in rainy versus 3.25 days in dry). The measurement of the vectorial capacity of Ae. aegypti in catholic churches could help to understand the dynamics of transmission of arboviruses in sites with high human aggregation.     

Effects of warming climate on early-season carbon allocation and height growth of defoliated mountain birches

Tree carbohydrate reserves are usually compromised following insect outbreak, which results in a delay in leaf emergence and a reduction in growth, especially in cold environments. However, in recent times, severe defoliation of subarctic mountain birches (Betula pubescens ssp. czerepanovii) by the winter moth (Operophtera brumata) has not induced such responses. This may be the result of a warming climate stimulating plant primary metabolism. We examined if increasing thermal sum (sum of daily mean temperatures above +5 °C, d.d.) and complete foliage loss affected the concentrations of carbohydrates in sap, juvenile leaves, and fine roots of mountain birches in northern Finland and Norway. The sampling was conducted at the beginning of the growing season, two years after the insect outbreak. We also investigated the morphologic properties of mature leaves and the shoot growth of the trees. Our results showed that the carbohydrate concentrations in leaves and roots (averages 67.8 and 12.5 mg g^?1 DW, respectively) decreased in defoliated trees with increasing thermal sum (>400 d.d.), whereas the response in intact trees was the opposite. The carbohydrates in the sap were unaffected by defoliation or thermal sum accumulation. The leaf area of mature leaves and the height growth of long shoots were greater in trees at warmer sites, irrespective of defoliation. However, defoliation increased the leaf weight per area (SLW: specific leaf weight). We conclude that under warmer growing conditions, low early-season leaf and fine root carbohydrate concentrations of previously defoliated trees cannot be used as indicators of aboveground growth.     

Gypsy moth parasitoids in the declining outbreak in Lithuania

A 3 year study was conducted on the parasitoids of gypsy moth larvae in two reducing outbreak areas in Lithuania. Overall parasitism of 25.0 ± 2.0% in the first post-culmination year was significantly lower than the 36.3 ± 1.4 and 35.2 ± 1.4% parasitism in the two subsequent years. When analysed in terms of the life stage at which the host was collected, the total parasitism over 3 years was constantly increasing from 3.1 ± 0.8 in the first to 72.5 ± 2.9% in the sixth instar. Parasetigena silvestris R.-D. dominated causing 48.7 ± 1.5% parasitism and 16.7 ± 0.6% larval mortality preferably in late instars. Phobocampe disparis Vier. contributed to 21.9 ± 1.2% parasitism and 7.5 ± 0.5% mortality recovering from early instar larvae. Meteorus pulchricornis Wes. parasitized 4.3 ± 0.6% gypsy moth larvae causing 1.5 ± 0.2% mortality and a few Apanteles species provided 2.8 ± 0.6% parasitism and 1.0 ± 0.2% mortality. The gypsy moth in Lithuania was reported to act as host for Rogas sp. (Hym., Braconidae) and Siphona boreata Mes. (Dipt., Tachinidae).     

Competition between the gypsy moth, Lymantria dispar, and the northern tiger swallowtail, Papilio canadensis: interactions mediated by host plant chemistry, pathogens, and parasitoids

The gypsy moth, Lymantria dispar, and the northern tiger swallowtail, Papilio canadensis, overlap geographically as well as in their host ranges. Adult female swallowtails are incapable of distinguishing between damaged and undamaged leaves, and the opportunities for competition between these two species are numerous. We designed field and laboratory experiments to look for evidence of indirect competition between P. canadensis and L. dispar larvae. Swallowtail caterpillars were reared in the laboratory on leaves from gypsy-moth-defoliated and undefoliated trees to explore host-plant effects. We tested for pathogen-mediated interactions by rearing swallowtail larvae on both sterilized and unsterilized leaves from defoliated and undefoliated sources. In addition, we measured the effects of known gypsy moth pathogens, as well as gypsy moth body fluids, on the growth and survival of swallowtail larvae. Field experiments were designed to detect the presence of parasitoid-mediated competition, as well: we recorded parasitism of swallowtail caterpillars placed in the field either where there were no gypsy moth larvae present, or where we had artificially created dense gypsy moth populations. We found evidence that swallowtails were negatively affected by gypsy moths in several ways: defoliation by gypsy moths depressed swallowtail growth rate and survival, whether leaves were sterilized or not; sterilization significantly reduced the effect of defoliation, and gypsy moth body fluids proved lethal; and swallowtail caterpillars suffered significantly increased rates of parasitism when they were placed in the field near gypsy moth infestations.     

Effect of plant secondary metabolites on susceptibility of insects to entomopathogenic microorganisms

The effect of a number of plant extracts on the susceptibility of experimental insects to enthomopathogenic microorganisms has been studied. It is shown that the weight of the wax moth Galleria mellonella larvae tends to decrease by 30–50% under the treatments of polar and nonpolar extracts from the ledum sprouts and the reindeer lichen, while the crude hemlock extract had the opposite effect, contributing to the larva weight gain by approximately 30%. The treatment with the reindeer lichen extract causes synergistic effects on mortality from both the nuclear polyhedrosis virus and the fungal infection in the gypsy moth Lymantria dispar and the wax moth, respectively. It has been determined that the main components of this extract are perlatolic acid, usnic acid, and a third component whose exact chemical identity is still unknown. The usnic acid is the most prospective additive component to entomopathogenic microorganisms. The treatment with the usnic acid caused the increase in mortality from the entomopathogenic fungi Metarhizium robertsii and Beauveria bassiana in the Colorado potato beetle Leptinotarsa decemlineata and the wax moth. However, the maximum effect occurs only after the treatment with the crude extract, which can be explained by either the combined effects of all the extract components or the change in a range of the properties of the components in the presence of the other crude extract components.     

Long-term dynamics of vegetation indices in dark coniferous forest after Siberian moth disturbance

This study considers long-term dynamics of the vegetation indices derived from Landsat imagery of the period from 1989 to 2014. The mass death and damage of forests by Siberian moth occurred in dark coniferous taiga in 1994–1996. The images have covered both altered (disturbed) and background forest conditions. The case study of the forest massive is located in the model area of the Angara Taiga Region of Eastern Siberia (Krasnoyarsk krai). The values of spectral brightness of satellite images are represented by produced index images of NDVI vegetation index and shortwave vegetation index SWVI. The study employed forest-surveying materials from 1992 and data on the degrees of forest damage during the first (in 1995) and second (in 1996) year of Siberian moth outbreak. The latter was obtained by forest-pathology research using production-scale spectrozonal aerophotography. The average background values of indices have gradually decreased with the forest age or remained constant, excluding the young growth stage and 200-year-old light coniferous forests. High seasonal variability of NDVI compared to SWVI is the key to use satellite data for the timeframe of a week in June for every year to analyze long-term dynamics. We have approved the conclusion of other researchers that both the mean and the coefficient of variation of SWVI are the most informative in the evaluation of the degree of Siberian moth damage of forests. We recommend recognizing three degrees of forest damage by Siberian moth—light, moderate, and severe (continuous). Long-term dynamics of vegetation indices in disturbed forests has been marked with demutation and inhomogeneity of stand cover. Taking into account the intensity and frequency of wildfires, it is highly probable that reforestation will not occur in dark coniferous forests. Therefore, the regular satellite monitoring of the sites of Silk moth occurrence would be useful.