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This study analyzed the relationship between characteristics of annual tree ring time series and the intensity of attacks on forest stands by forest insects. Using tenets of the fluctuation–dissipation theorem (which is widely used in physics), time series parameters are proposed that can help to assess the susceptibility of a forest stand to insect pests. The proposed approach was applied to evaluate differences in parameters of tree ring widths among outbreaks of the pine looper, Siberian silk moth, and spongy moth. A comparison of trees characteristics between outbreak locations and undamaged forest stands (control) showed that the tested parameters statistically significantly differed between the outbreak locations and control stands and can be used to assess the risk of pest outbreaks in forest stands.

Validation of models of Land Use and Cover Change often involves comparing maps of simulated and reference change. The interpretation of differences between simulated and reference change depends on the characteristics of the process being studied. Our paper focuses on validation of models of one-way land change processes that spread in space. Our objective is to develop a method for validation of one-way land change models, such that the method provides objective information about the spatial distribution of errors. Using distance analysis on reference data, we build a baseline model for comparison with simulations. We then simultaneously compare the four maps of reference at initial time, reference at final time, simulation at final time, and baseline at final time. We also use Total Operating Characteristic curves and multiple-resolution map comparison. We illustrate the methods with a simulation of forest insect infestations. The methods give insights concerning the reference data and the spatial distribution of misses, hits, and false alarms with respect to initial points of infestations. The new methods reveal that the simulations underestimated change near initial points of spread. The spatial distribution of errors is a topic of land change models that deserves attention. For models of one-way, geographically-spreading processes, we recommend that validation should distinguish between near and far allocation errors with respect to initial points of spread.

Emerald ash borer (EAB), an invasive forest insect from Asia, has impacted vast areas in the United States and European Russia. To proactively understand the social impact of an EAB invasion in Europe and the USA, this study analyzed visitors’ preferences and preference heterogeneity for EAB-impacted forest scenarios in Vienna, Austria (n = 510) and Minneapolis, USA (n = 307). An image-based discrete choice experiment with latent-class analysis among on-site completed questionnaires in Vienna indicated four different visitor segments based on trade-offs among biophysical, social and viewscape elements. Within the forested environment, two segments placed greater importance on (bio)physical attributes and two on social aspects. Although all segments preferred a non-impacted ash forest, only one of the four identified the attribute describing EAB impacts and forest management as the most important attribute. Rather, visitor numbers and background viewscapes were more important than EAB impact and management to differentiate landscape preferences for three of the four segments. Differences in preferences were found between the Vienna and Minneapolis samples. Vienna respondents showed a higher preference for more natural conditions, disliked more the initial stage of EAB impact and placed more importance on background viewscapes and visitor numbers. Forest managers and greenspace planners need to consider the entirety of the forested condition, social and visual, for effective management and address that visitors differ in their preferences for all of these conditions.

Insect population dynamics are closely related to ‘human’ ecological and economic environments, and a central focus of research is outbreaks. However, the lack of molecular-based investigations restricts our understanding of the intrinsic mechanisms responsible for insect outbreaks. In this context, the moth Dendrolimus punctatus Walker can serve as an ideal model species for insect population dynamics research because it undergoes periodic outbreaks. Here, high-throughput whole-transcriptome sequencing was performed using D. punctatus, sampled during latent and outbreak periods, to systemically explore the molecular basis of insect outbreaks and to identify the involved non-coding RNA (ncRNA) regulators, namely microRNAs, long non-coding RNAs, and circular RNAs. Differentially expressed mRNAs of D. punctatus from different outbreak periods were involved in developmental, reproductive, immune, and chemosensory processes; results that were consistent with the physiological differences in D. punctatus during differing outbreak periods. Targets analysis of the non-coding RNAs indicated that long non-coding RNAs could be the primary ncRNA regulators of D. punctatus outbreaks, while circular RNAs mainly regulated synapses and cell junctions. The target genes of differentially expressed microRNAs mainly regulated the metabolic and reproductive pathways during the D. punctatus outbreaks. Developmental, multi-organismal, and reproductive processes, as well as biological adhesion, characterized the competing endogenous RNA network. Chemosensory and immune genes closely related to the outbreak of D. punctatus were further analyzed in detail: from their ncRNA regulators’ analysis, we deduce that both lncRNA and miRNA may play significant roles. This is the first report to examine the molecular basis of coding and non-coding RNAs’ roles in insect outbreaks. The results provide potential biomarkers for control targets in forest insect management, as well as fresh insights into underlying outbreak-related mechanisms, which could be used for improving insect control strategies in the future.

Outbreaks of insect pests periodically cause large losses of volume in Canada’s forests. Compounded with climate change, outbreaks create significant challenges for managing the sustainable delivery of ecosystem services. Current methods to monitor damage by these pests involve both field and aerial surveys. While relatively cost effective and timely, aerial survey consistency and spatial coverage may be insufficient for detailed monitoring across Canada’s vast forest-land base. Remote sensing can augment these methods and extend monitoring capabilities in time and space by incorporating knowledge of pest-host interactions and of how damage translates into a remote sensing signal for detection and mapping. This review provides a brief introduction to major forest insect pests in Canada (two bark beetles (Coleoptera: Curculionidae) and six defoliators) and the damage they cause, a synthesis of the literature involving aerial survey and remote sensing, and a discussion of how these two approaches could be integrated into future pest monitoring from a Canadian perspective. We offer some lessons learned, outline roles that remote sensing could serve in a management context, and discuss what ongoing and upcoming technological advances may offer to future forest health monitoring.

With global warming, recent winters in Switzerland have been milder than in previous decades, and this trend is predicted to continue. Survival during the cold season could increase for insect species sensitive to winter cold events. Forest pests, such as the pine processionary moth (Thaumetopoea pityocampa) and green spruce aphid (Elatobium abietinum), as well as some crop pests, such as the southern green stink bug (Nezara viridula), could overwinter more easily. These species are affected by temperatures below –12°C or below –8°C. In this study, we examined whether changes in winter minimum temperatures (Tmin) could potentially favour the winter survival of these pest species in various places in Switzerland. We analysed long-term daily Tmin data from the period 1980–2019 at 67 locations. We then used two climatic scenarios (RCP2.6 and RCP8.5) to analyse daily Tmin in 2020–2099. We determined the number of days with Tmin below –8°C or –12°C and the frequency of years with at least one day below these thresholds. Our results show that the frequency of cold days has decreased over the last 40 years, even though winter Tmin has increased less than yearly Tmin. However, the –8°C threshold was still reached in most years, except on the Southern side of the Alps. The –12°C threshold was reached almost every year above 800 m, but infrequently at lower elevations. Our results indicate that, by the end of the 21st century, temperatures below –12°C will occur only infrequently up to 1700 m in Switzerland, and years with occurrences of temperatures below –8°C will become rare at lower elevations. Future temperature conditions can thus be expected to favour some crop pests, by enabling them to overwinter more easily on the Swiss Plateau, as well as some forest pests, which will likely reach higher elevations.

Financial support was provided by the Department of Science and Technology (DST)/National Research Foundation (NRF) Centre of Excellence in Tree Health Biotechnology. This project was supported by multiple grants from the NRF, South Africa, including the grant specific unique reference number (UID) 83924.

Canada is host to a number of native and introduced forest insects that negatively affect the goods and services provided by forests. Some insects affect forests on a fairly predictable, ongoing basis, while others have impacts that are intermittent, difficult to predict, and sometimes catastrophic. Economic analysis has provided important insights that have informed our understanding of the impact of forest pests and pest management. At the same time, interactions between forests, forest insects, forest management, and economic welfare are complex, and credible assessments may be time consuming and may not always provide results with the certainty sought by policy-makers. This paper reviews the contribution of economics to forest pest management in Canada and suggests future directions for this important field of research.

Insects use semiochemicals to mediate important behaviours such as mating, oviposition, and foraging for resources. Chemical ecology research aims to identify these message-bearing chemicals and develop synthetic copies of semiochemicals for use in integrated pest management (IPM). There has been, and continues to be, an extensive research effort to understand the chemical ecology of various insects considered to be pests of forests in Canada. Canadian chemical ecology research has had an impact on IPM of forest insect pests in Canada and around the world. Canadian researchers have been involved in the identification of semiochemicals used by forest insects and the development and implementation of semiochemical-based management tactics for forest pest management. Semiochemicals have been incorporated into forest pest management for a variety of insect taxa primarily as tools to monitor and control forest insect pests in Canada. The goals of the current review are to: (1) highlight research conducted on semiochemical-based management of forest pests in Canada; (2) discuss the current and potential uses of semiochemicals in IPM of forest pests in Canada; and (3) evaluate potential areas for increased research and implementation of semiochemicals into the management of forest pests in Canada.

The ability of insect pathogens (in particular viruses) to cause long-term stable limit cycles in their hosts was first demonstrated theoretically by Anderson and May (1980, 1981). Since then, there has been extensive discussion and controversy about whether the cycles seen in temperate forest insects (Varley 1949; Baltensweiler 1964; Baltensweiler et al. 1977) are caused by pathogens (Myers 1988) and whether the addition of greater biological detail to the simple Anderson and May model increases or decreases the likelihood of cycles. The Anderson and May model is a set of coupled ordinary differential equations, related to the Lotka-Volterra predator-prey model, in which neither the host nor the pathogen shows any density-dependent self-regulation. Since the type of forest insect that shows long-term cycles frequently severely depletes its food supply, it is natural to ask whether the addition of host selfregulation makes cycles more likely. This was first done by Bowers et al. (1993), who concluded that density dependence was unlikely to increase the probability of population cycles, although the opposite conclusion was reached the following year by Dwyer (1994). The apparent contradiction was reconciled by White et al. (1996), who showed that the two studies had incorporated host self

The article studies the species varieties of forest insects in the centers of attack with determination of the tree stocking degree. The major insect species are represented by such samilies as bark beetlesipidae capricon betles – Cerambycidae. The artice considers the effect of insect on common pipe decaying in the location of pine fungus. It has been substantiated that the formalion of forest insect attack centers depend on the age of trees. Concentration of larger and lasser pine – shoot beetles dominates in the forest of 40 years of age. They intensify the effect of pine fungus with further weakening the trees. Following the results of investigation it has been determined that such insects as larger pine-shoot beetle lesser pine-shoot beetle, black pine Capricorn beetle, blue pine char cool beetle, Curkulio glandium are the synergist of Heterobasidion annosum finvader. Обгрунтовано значення ентомологічного фактора у розповсюдженні кореневої губки сосни звичайної , а також видового складу стовбурових шкідників в осередках Heterobasidion annosum з визначенням ступеня заселеності дерев . Основні види стовбурових шкідників представлені родинами : короїди – Ірі d ае , вусачі – Се rambycid ае , златки – В uprestid ае , довгоносики – С ulculionida). Предметом роботи є збудник кореневої губки сосни звичайної в умовах Корабельного лісництва державного підприємства «Житомирське лісове господарство». Метою роботи є вивчення впливу стовбурових шкідників на всихання сосни звичайної в осередках кореневої губки. Встановлено, що ф ормування осередків стовбурових шкідників залежить від віку насаджень – осередки великого і малого соснового лубоїдів переважають в насадженнях до 40 років, що призводить до підсилення шкідливої дії кореневої губки. Основними методами проведення робіт є фітопатологічна експертиза соснових насаджень, а також проведення обстежень соснових деревостанів з визначенням характеру всихання в залежності від ступеня ураження як збудником кореневої губки сосни звичайної, так і розповсюдження збудника ентомологічним шляхом в соснових деревостанах. За результатами роботи встановлено, що формування осередків стовбурових шкідників залежить від віку насаджень – осередки великого і малого соснового лубоїдів переважають в насадженнях до 40 років, призводячи до підсилення шкідливої дії кореневої губки і значного ослаблення насадження в подальшому. В результаті проведених досліджень було виявлено, що великий сосновий лубоїд, малий сосновий лубоїд, чорний сосновий вусач, синя соснова златка, соснова жерднякова смолівка є синергітами збудника Heterobasidion annosum. Сферою застосування результатів є лісогосподарські підприємства різних форм власності з метою збереження та захисту лісових насаджень від збудника кореневої губки в умовах зони Полісся України. Висновки досліджень полягають в тому, що для повноцінного відновлення лісів, з лісогосподарської точки зору найбільш ефективнішим вирішенням проблеми є проведення рубок догляду, тоді, коли приріст починає сповільнюватися, отже вдається зберегти максимальний приріст дерев що залишаються, а від реалізації заготовленої при рубках догляду деревини отримати прибуток не чекаючи, поки вони будуть знищені шкідниками. В перспективі є сенс в подальших дослідженнях штучно створених насаджень які ще довгий час не зможуть функціонувати без систематичного і регулярного лісогосподарського та лісосанітарного догляду, причому слід чітко розуміти, що цьому повинен передувати досить тривалий період трансформації штучних лісових фітоценозів до природного стану. Тому важливим завданням лісівників в ДП „Житомирське ЛГ” у цьому напрямку є підтримання стабільного фітосанітарного стану насаджень і всебічна стимуляція природних саморегуляційних процесів в лісових екоценозах.

Surveying multiple invasive pest species at the same time can help reduce the cost of detecting new pest invasions. In this paper, we describe a new method for mapping the relative likelihood of pest invasion via plant propagation material in a geographic setting. The method simulates the invasion of a range of pest species, including arrival in an uninvaded area, spread, and survival in a novel landscape, using information on the spatial and temporal distribution of the suitable host crop species and tentative knowledge of the spread and survival capacities of the target pests. The methodology is applied to a gridded map in which each map cell represents a site in a landscape. The method uses stochastic simulations to depict plausible realizations of the invasion outcomes and estimate the distribution of pest invasion likelihood for each cell in the area of concern. The method then prioritizes the cells based on the stochastic invasion outcomes using a pairwise stochastic dominance rule and a hypervolume indicator. We demonstrate the approach by assessing the relative likelihood of pest invasion for strawberry production in Finland. Our method helps to differentiate sites in a landscape using both the estimates of pest invasion risk and their uncertainty. It can be applied to prioritize sites for plant health surveys and allocate survey resources among large geographic regions. The approach is generalizable and can be used in situations where knowledge of the harmful pest species is poor or nonexistent.

Carbaryl is regarded among the most effective, economically viable, and ecologically-compatible insecticides available for protecting conifers from bark beetle attack in the western United States. Treatments are typically applied in spring prior to initiation of bark beetle flight for that year. We evaluated the efficacy of spring and fall applications for protecting individual lodgepole pine, Pinus contorta Dougl. ex Loud, from mortality attributed to mountain pine beetle, Dendroctonus ponderosae Hopkins, the most notable forest insect pest in western North America. Both spring and fall treatments of 2.0% a.i. carbaryl (Sevin ® SL) were efficacious for two field seasons, while results from a third field season were inconclusive due to insufficient beetle pressure. We discuss the implications of these and other results to the management of D . ponderosae .

Eastern (Tsuga canadensis) and Carolina hemlocks (T. caroliniana) of eastern North America have been attacked by the non-native hemlock woolly adelgid (Adelges tsugae Annand) (HWA) since the first half of the 20th century. Unlike most insects, HWA develops through one generation from fall to late winter, exposing this insect to the lethal effects of winter temperatures. The mortality inflicted by winter temperatures on HWA determines the surviving population density as well as its ability to spread to uninfested areas. With the ongoing changes in climate, knowledge of this species’ ability to survive and spread in the future can help land managers prepare for its management. This study began during the winter of 2014 and ended in the spring of 2017. During this period, winter mortality of HWA was recorded at 100 sites from Maine to Georgia (n = 209). Changes in population density from the sistens to the succeeding progrediens generation were recorded at 24 sites (n = 35). Models were developed to predict HWA mortality using the lowest minimum temperature prior to the mortality assessment date, the number of days with mean temperature T. canadensis’ distribution as minimum temperatures are predicted to increase at a greater rate. This will result in an increase in density throughout its current distribution and expansion northward causing an increase in its impact on eastern Tsuga spp. Published version

Emerald ash borer (EAB) (Agrilus planipennis Fairmaire), the most destructive forest insect to have invaded North America, has killed hundreds of millions of forest and landscape ash (Fraxinus spp.) trees. Several artificial trap designs to attract and capture EAB beetles have been developed to detect, delineate, and monitor infestations. Double-decker (DD) traps consist of two corrugated plastic prisms, one green and one purple, attached to a 3 m tall polyvinyl chloride (PVC) pipe supported by a t-post. The green prism at the top of the PVC pipe is baited with cis-3-hexenol, a compound produced by ash foliage. Surfaces of both prisms are coated with sticky insect glue to capture adult EAB beetles. Double-decker traps should be placed near ash trees but in open areas, exposed to sun. Double-decker trap construction and placement are presented here, along with a summary of field experiments demonstrating the efficacy of DD traps in capturing EAB beetles. In a recent study in sites with relatively low EAB densities, double-decker traps captured significantly more EAB than green or purple prism traps or green funnel traps, all of which are designed to be suspended from a branch in the canopy of ash trees. A greater percentage of double decker traps were positive, i.e., captured at least one EAB, than the prism traps or funnel traps that were hung in ash tree canopies.

Forest insects are major disturbances that induce tree mortality in eastern coniferous (or fir-spruce) forests in eastern North America. The spruce budworm (SBW) (Choristoneura fumiferana [Clemens]) is the most devastating insect causing tree mortality. However, the relative importance of insect-caused mortality versus tree mortality caused by other agents and how this relationship will change with climate change is not known. Based on permanent sample plots across eastern Canada, we combined a logistic model with a negative model to estimate tree mortality. The results showed that tree mortality increased mainly due to forest insects. The mean difference in annual tree mortality between plots disturbed by insects and those without insect disturbance was 0.0680 per year (P0.0001, T-test), and the carbon sink loss was about 2.87t C ha(-1) year(-1) larger than in natural forests. We also found that annual tree mortality increased significantly with the annual climate moisture index (CMI) and decreased significantly with annual minimum temperature (T min), annual mean temperature (T mean) and the number of degree days below 0°C (DD0), which was inconsistent with previous studies (Adams et al. 2009; van Mantgem et al. 2009; Allen et al. 2010). Furthermore, the results for the trends in the magnitude of forest insect outbreaks were consistent with those of climate factors for annual tree mortality. Our results demonstrate that forest insects are the dominant cause of the tree mortality in eastern Canada but that tree mortality induced by insect outbreaks will decrease in eastern Canada under warming climate.

Forest pests are one of the most important factors disturbing forest ecosystems, by impacting forestry economy, ecosystem services, biodiversity, and sustainable ecosystem management. Monitoring the occurrence of forest pests offers clues to understand their impacts on the forest ecosystem and develop a sustainable ecosystem management strategy. This special issue is designed to create a better understanding of the changes and impacts of forest pests according to forest changes, caused by natural or anthropogenic causes. There are 13 papers published in this special issue, covering several issues concerning forest pests. Two of the papers reviewed the changes in forest pests in Korea or Poland. The remaining twelve papers covered issues concerning the monitoring, assessment, and management of forest pests. Through this special issue, we expect to contribute towards the improvement of our knowledge of the structures and processes in forest ecosystems relating to forest pests and fundamental information for the effective management of forest pests.

Detection of newly established populations of Agrilus planipennis Fairmaire, the most destructive forest insect to invade the United States, remains challenging. Regulatory agencies currently rely on artificial traps, consisting of baited three-sided panels suspended in the canopy of ash (Fraxinus spp.) trees. Detection trees represent another survey option. Ash trees are girdled in spring to attract ovipositing A. planipennis females then debarked in fall to assess larval presence and density. From 2008-2010, systematic grids of detection trees and artificial traps were established across a 390-km(2) area for the SLow Ash Mortality pilot project. We compared probabilities of detection associated with detection trees and artificial traps along varying A. planipennis density proxies estimated as distance-weighted averages of larval counts (detection trees) or adult captures (traps) within 800 m of each detection tree or trap. Detection trees were consistently more likely to be positive, that is, detect A. planipennis, than traps in all three years, even when traps were placed in canopies of detection trees. Probability of detection with a single detection tree was >50% when density proxies for the area were

Forest dependent people, Incessant poverty in India, Forest insect sector, Institutional linkages, Conservation of insect biodiversity In India, forest based insect enterprises has never been linked up with any forest management activity, either as a forest conservation strategy or to reduce the poverty in forested area. This investigation indicated that when forest dependent people are associated with forest insect industry (FII) like forest sericulture, lac culture or apiculture; this income generating activity links livelihood with forest conservation, and generates a viable model of collaborative forest management (CFM). In this model different stakeholders work together as a coherent entity for unified goal of managing the forest for well-being of the poor people in fringe areas. Article summaries and evaluates the prospect of India specific forest insect industry, and discusses how and to what extent integration of FII could be a viable livelihood component in CFM to conserve the forest and insect biodiversity. We analysed a case study on forestbased rearing of tropical tasar silkworm rearing in Central India from CFM perspective. Arguments in this communication are intended to provide forest managers and policy-makers with necessary input to consider location specific FII in CFM mode to provide a continuous source of small income to forest dependent people to ensure long lasting success of their forest management endeavours.

The paper is concerned with the investigation of the model of dynamics of population of caterpillar budworm (Choristoneura fumiferana). The system solutions behavior depending on the parameters values has been investigated, conditions of origination of canard curves have been found.

Model testing procedures represent a major challenge in the development of agent-based models (ABMs). However, they are required stages for a model to be accepted and to serve as a forecasting, management or decision-making tool. This study presents a comprehensive approach for testing ForestSimMPB, an agent-based model (ABM) designed to simulate mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins, outbreaks at the scale of individual trees. ForestSimMPB is a complex system model that is using swarming intelligence, capable to represent individuals’ behaviours and spatial interactions that influence their surrounding environment. Swarm Intelligence (SI) methods are integrated into the ABM in order to reproduce the collective reasoning and indirect communication of autonomous agents representing MPB behaviour within the forest environment. Model testing approach consist of verification, calibration, sensitivity analysis, validation and qualification stages. Model testing is accomplished by simulating MPB infestations using both the ForestSimMPB model and a Random–ABM model that serves as a null model. Outcomes comparison and assessment are performed using raster-based techniques as well as spatial metrics. Aerial photographs of the British Columbia, Canada study sites are used in this model testing approach. Results indicate that ForestSimMPB model representations of MPB outbreaks are more similar than Random model representations to the spatial distribution of MPB-dead trees.

An analysis of forest tent caterpillar Malacosoma disstria defoliation records from Ontario and Quebec over the period 1938–2002 indicates that outbreaks recur periodically and somewhat synchronously among regions of the two provinces. Cluster analysis revealed that the most strongly periodic, large-scale, synchronized fluctuations occurred within three regions: northwestern Ontario, eastern Ontario/western Quebec and southeastern Quebec. Defoliation in the vast surrounding hinterlands tended to be infrequent and sporadic, loosely tracking defoliation in the core outbreak regions. One small cluster in northeastern Ontario stood out as anomalous, as a result of an increasing trend in the duration of periodic defoliation episodes, marked by an unprecedented double-wave of defoliation that persisted from 1992 to 1999. This is the precise area where, in the early 2000s, trembling aspen Populus tremuloides stems were mapped as being in a state of decline of unprecedented severity and extent. Our results suggest forest tent caterpillar has the potential to cause significant impacts on forest health and, hence, carbon budgets in east-central Canada and that the forest tent caterpillar deserves more attention as a model system of forest insect disturbance ecology.

Landscape composition and physiognomy affect community structure and species distribution across space and time. The pine processionary moth (PPM) (Thaumetopoea pityocampa Den. & Schiff., Lepidoptera, Notodontidae) is a common pine defoliator throughout southern Europe and Mediterranean countries. We surveyed the spatiotemporal distribution of the PPM in a pine plantation forest in southwestern France and used the density of the winter nests as a proxy for population density. The study spanned 4 years (2005–2008) and showed a high temporal variability in nest density. We found a strong edge effect with nest densities at stand edges more than twice as large as within-stand densities. At the landscape scale, the spatial distribution of the moth exhibited a significant spatial autocorrelation in 3 out of 4 years of our study. The spatial scales of the autocorrelation ranged from ca. 2 km to more than 22 km. We found a positive correlation between spatial distributions corresponding to certain sampling years, but the relationship was not systematic. Landscape configuration appeared to be an important driver of the PPM spatial pattern. Bivariate Moran’s I correlograms showed that patch richness density as well as the percentage of local landscape covered by various land uses were correlated with population density. The study showed that accounting for landscape characteristics may be important in order to understand forest insect pest distribution, even in cases where the host species is abundant and homogeneously distributed throughout the study area, e.g., pure plantation forests.

Between 1936 and 1996, the Forest Insect and Disease Survey (FIDS) of the Canadian Forest Service of Natural Resources Canada surveyed eastern white pine (Pinus strobus L.) throughout Atlantic Canada. During those years, FIDS reported its insect and disease findings in a wide variety of regional and national reports and in the scientific literature. The National Forest Health Database contains these electronic records and indicates the distribution and relative importance of forest diseases and fungi for many tree species in Atlantic Canada. This paper is a frequency analysis of the fungal diseases recorded from the Atlantic provinces in the National Forest Health Database and reported in the various Maritime, Newfoundland and national FIDS reports. The significant eastern white pine diseases (e.g., white pine blister rust – Cronartium ribicola J.C. Fisch.) that are established in Atlantic Canada as well as other diseases that are found elsewhere in Canada, but not yet in the Atlantic provinces are discussed. Occurrence data for 40 of the less frequently collected fungal species are presented in a summary table. Key words: white pine blister rust, Cronartium ribicola, eastern white pine, Pinus strobus, Scleroderris canker, Gremmeniella abietina, Annosus root rot, Heterobasidion annosum, white pine root decline, Leptographium procerum, needle cast, Lophodermium pinastri, brown felt fungus, Septobasidium pinicola, Atlantic Canada, forest disease

Discrete mathematical model is selected for description of green oak leaf roller (Tortrix viridana L.) population dynamics. Experimental data set from Rubtsov [Rubtsov, V.V., 1992. Models of Oscillation Processes in Forest Ecosystems, Forest Institute, Moscow, Russian Federation, p. 39 (in Russian)] is analyzed from the standpoint of phenomenological theory of forest insect population dynamics [Isaev, A.S., Khlebopros, R.G., Nedorezov, L.V., Kiselev, V.V., Kondakov, Yu. P., 1984. Dynamics of Forest Insects Populations, USSR, Nauka, Novosibirsk, p. 224 (in Russian); Isaev, A.S., Khlebopros, R.G., Nedorezov, L.V., Kiselev, V.V., Kondakov, Yu.P., Soukhovol'sky, V.G., 2001. Population Dynamics of Forest Insects, Russian Federation, Nauka, Moscow, p. 347 (in Russian)]. For checking hypotheses confidence for fitting of experimental time series, Moran–Ricker model, Maynard Smith–Slatkin model, and some others are used. Selection of statistical criteria for estimating parameter's values is discussed. In addition, probabilities of realizations of several dynamical regimes are estimated.

Wood borers are important forest insect pests and difficult to be controlled owing to their concealed behavior. However, parasitic wasps can effectively ascertain and parasitize wood borers as well as other concealed pests by using special searching, finding and attacking mechanisms, which have been developed during the course of long-term coevolution with their hosts. The present paper summarizes the behavioral mechanisms of parasitic wasps involved in searching and locating their concealed hosts. Parasitic wasps can accurately find the location of their hidden hosts and then parasitize them, usually by using olfactory semiochemicals from hosts (lavare and adults), host frass and symbiotic microorganisms in host galleries; visual signals from color contrast of plant surface; contact stimuli from characters of host physical defense; substrate vibrations produced by host feeding and movement; infrared radiation from host activities and metabolizability. Some parasitic wasps may integrate the information of several stimuli from different sources to enhance the reliability and accuracy of host locations. In addition, the potentials for utilizing the host location signals of parasitoids in biological control are discussed.

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала. Features of external environmental factors (such as electromagnetic radiation in certain spectral bands) influencing pheromone molecules, which are carriers of information for forest insects in the search of the opposite sex, were examined. Stability of pheromone molecules for external influences has been studied for siberian moth Dendrolimus superans sibiricusTschetv., pine moth Dendrilimus piniL., gypsy moth Lymantria disparL., for xylophages Ips typographus L., Monochamus urussovi Fish. and Monochamus galloprovincialis Oliv. Properties of pheromone molecules were evaluated by calculations using quantum-chemical method B3LYP. Existing methods of quantum-chemical calculations are useful for analyzing the properties of quite small and uncomplicated molecules of forest insect pheromones. The calculations showed that the molecules of insect pheromones are able to absorb light in the ultraviolet range and move into an excited state. The values of dipole moments, the wavelengths of the absorption, atomic and molecular electronic properties of pheromones in the ground and excited states were calculated. The calculations showed that for the reaction of pheromones with oxygen an energy barrier is somewhat higher than for reactions of pheromones with water vapor. The worst reaction of pheromones with water molecules likely to pheromones such molecules whose dipole moment is comparable to the dipole moment of water. Quantum-chemical characteristics of the pheromone molecules can be linked to specific behavior of the insects.

To better understand the role of habitat quality and boundaries on population dynamics at the landscape scale, we develop a model combining a spatially implicit approach, a spatial population Leslie-type model and an implicit model of habitat fragmentation. An original approach of elasticity permits to identify which types of element and boundary influence the most population viability according to the wood fragmentation degree. The studied species is a corridor forest insect sensitive to fragmentation ( Abax parallelepipedus, Coleoptera, Carabidae). We show that a single large patch of wood is better than several small patches for the population viability. To cite this article: J.-B. Pichancourt et al., C. R. Biologies 329 (2006).

The goal of this project was to determine the ability to detect forest insect disturbances occurring over a 6 year period using a remote sensing change detection approach. The study area in central British Columbia, Canada, has been experiencing an epidemic outbreak of bark beetles. The actual location and number of trees attacked by mountain pine beetle (Dentroctonus ponderosae Hopkins) were determined by annual surveys using a helicopter and a global positioning system (GPS). In this study, mountain pine beetle red-attack trees, infested between 1995 and 2001, were detected with an enhanced wetness difference index (EWDI), which was created using a 1995 and 2001 Landsat image pair. Red-attack damage was detected with an accuracy (true positive rate) of 74% using all years of the helicopter GPS survey data as validation. Assessments of the classification were subsequently undertaken that compared the EWDI-derived red-attack locations to each year of available validation data. The results of this analysis...

Nous présentons un survol des programmes de lutte biologique envers les insectes forestiers en mettant l'accent sur des cas canadiens. Ces travaux de recherche sont examinés dans le contexte de la conservation, de l'introduction et de l'augmentation (par manipulation de l'environnement et lâchers inoculants et massifs) des ennemis naturels, et plus spécifiquement des parasitoïdes. Historiquement les études ont porté sur l'introduction de parasitoïdes exotiques pour la lutte aux insectes nuisibles introduits, un certain nombre de ces travaux ayant été fructueux. Des travaux plus récents ont consisté en des lâchers inoculants et massifs de parasitoïdes contre des insectes indigènes afin d'établir de nouvelles relations hôte-parasitoïde dans le but de réduire les populations d'insectes indésirables. Ces nouvelles techniques n'ont démontré que des résultats limités et les recherches se poursuivent dans cette voie. Les stratégies actuelles d'utilisation d'ennemis naturels sont le lâcher massif d'espèces indigènes contre des espèces nuisibles indigènes et la conservation des parasitoides indigènes par des applications sélectives d'herbicides et la gestion des forêts. Les prochaines avenues pour les programmes de lutte biologique incluront ces approches en plaçant l'accent sur les biotechnologies et la sélection génétique ou la manipulation de lignées recherchées pour les lâchers. Des études écologiques continues seront essentielles à l'obtention d'une meilleure compréhension des interactions entre ces parasitoïdes sélectionnés et les données forêt-arbre qui influenceront leur succès (interaction tritrophique). Ces données, à savoir la vigueur de l'arbre (résistance aux insectes), distribution spatiale et diversité, seront aussi visées pour la sélection afin d'améliorer l'impact des ennemis naturels des parasites dans l'environnement forestier., An overview of biological control programs against forest insect pests is presented with emphasis on Canadian case histories. The work is examined in the context of conservation, introduction, and augmentation (environmental manipulation and inoculative and inundative release) of insect natural enemies, specifically parasitoids. Historically, studies have concentrated on introductions of exotic parasitoids for control of introduced pests where a number of successes have been recorded. More recent work has entailed inoculative and inundative releases of parasitoids against native pests in an attempt to establish new host-parasitoid relationships to reduce pest populations. These have had limited success and are still being explored by Canadian researchers. Current strategies for using natural enemies are inundative release of native species against native pests and conservation of native parasitoids through selective insecticide timing and forest manipulation. Future directions in biological control programs will include these approaches with increased emphasis on biotechnology and the genetic selection or manipulation of 'desired strains' for release. Continued ecological studies will be essential to ensure a more complete understanding of the interaction between these 'selected parasitoids' and the forest/tree parameters which will influence their success (tri-trophic interactions). These parameters, such as tree vigour (pest resistance), spatial distribution and diversity, will also be targeted for selection to improve the effect of insect natural enemies in the forest environment.

International audience; Saproxylic beetles – associated with dead wood or with other insects, fungi and microorganisms that decompose it – play a major role in forest nutrient cycling. They are important ecosystem service providers and are used as key bio-indicators of old-growth forests. In France alone, where the present study took place, there are about 2500 species distributed within 71 families. This high diversity represents a major challenge for specimen sorting and identification. The PASSIFOR project aims at developing a DNA metabarcoding approach to facilitate and enhance the monitoring of saproxylic beetles as indicators in ecological studies. As a first step toward that goal we assembled a library of DNA barcodes using the standard genetic marker for animals, i.e. a portion of the COI mitochondrial gene. In the present contribution, we release a library including 656 records representing 410 species in 40 different families. Species were identified by expert taxonomists, and each record is linked to a voucher specimen to enable future morphological examination. We also highlight and briefly discuss cases of low interspecific divergences, as well as cases of high intraspecific divergences that might represent cases of overlooked or cryptic diversity.

Verbenone (4,6,6-trimethylbicyclo[3.1.1]hept-3-en-2-one) is an antiaggregant of the mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), a notable forest insect capable of causing extensive levels of tree mortality in western North America. Several formulations of verbenone are registered for tree protection, but failures in efficacy are not uncommon, particularly when applied during large infestations. A formulation of (-)-verbenone was developed (Specialized PheromoneLure Application Technology [SPLAT] Verb, ISCA Technologies Inc., Riverside, CA) and evaluated for protecting individual lodgepole pine, Pinus contorta Douglas ex Loudon, and small stands of P. contorta from mortality attributed to D. ponderosae. SPLAT Verb applied to individual P. contorta resulted in complete tree protection, while 93.3% mortality occurred in the untreated controls. Significantly fewer P. contorta were killed by D. ponderosae within 0.041-ha circular plots surrounding P. contorta treated with SPLAT Verb compared with the untreated control. In a second study, a smaller percentage of P. contorta were colonized and killed on 0.4-ha square plots treated with SPLAT Verb compared with the untreated control. No significant differences in levels of tree mortality were observed between the untreated control and another formulation of verbenone (7-g pouch) or between the 7-g pouch and SPLAT Verb. In a trapping bioassay, no significant differences were observed among captures in multiple-funnel traps at 1, 2, or 4 m from the point of release of SPLAT Verb. Significantly fewer D. ponderosae were collected at 1 and 2 m compared with 8 m. Significantly more D. ponderosae were captured at the farthest distance evaluated (16 m) than at any other distance. Our data indicate that SPLAT Verb is effective for protecting individual P. contorta and small stands of P. contorta from mortality attributed to D. ponderosae at moderate doses. The high levels of tree protection observed are attributed to the ability of applying release points (dollops) at high densities, and a larger zone of inhibition than reported for other formulations of verbenone. SPLAT Verb was registered by the U.S. Environmental Protection Agency for use on pines, Pinus spp., in 2013.