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In Europe, Xyleborinus attenuatus Blandford is considered an invasive bark beetle native to East Asia. We used the results of many local surveys and data from private and museum collections to get information on the distribution and abundance of X. attenuatus Blandford in the Czech Republic. The ambrosia beetle X. attenuatus Blandford is probably widespread throughout the territory of the Czech Republic, from the lowlands to the mountains, and has one generation per year in Central Europe. The flight activity lasts from mid-March to May, F1 adults emerge in August and September and overwinter in wood or in the ground under an infested tree. X. attenuatus Blandford predominantly occupies soft deciduous trees and so far there economic damage have not been reported yet. However, X. attenuatus Blandford is a vector of ambrosia fungi Ambrosiella spp. and Raffaelea spp., and therefore this ambrosia beetle should be monitored.

Castanea sativa is a type of cultivated chestnut tree found in the Czech Republic, growing in both lowland and midland regions. These trees are usually planted individually or in pairs, with over half of the plantings located in urban areas. One-fifth of chestnut trees thrive in parks, while chestnut orchards or forest stands make up only one-tenth of the areas where chestnut trees are located. In the Czech Republic, approximately 30 ha are covered by chestnut trees. Regeneration of chestnut trees occurs in only 6% of the localities due to regular lawn mowing. However, 40% of the surveyed forests showed signs of regeneration, demonstrating the species' ability to regenerate under Central European climate conditions. [ABSTRACT FROM AUTHOR]

Polydrusus aeratus Gravenhorst, 1807 is a pest of both coniferous and deciduous trees in forests. It is widespread throughout the Czech Republic from the lowlands to the mountains. Adult beetles occur from April to September. In the western Czech Republic, a number of 1- to 2-m tall Abies alba were recently damaged by P. aeratus adults at an altitude of 750 m. P. aeratus can damage older saplings that were damaged as young saplings by the pine weevil. The damage caused by P. aeratus is so for rather small but should not be neglected by foresters. As the ongoing climate change modifies the relationship between trees and pests, also currently indifferent species may become dangerous for forests in near feature. Therefore, scientists would focus also on relatively less dangerous species of pests, especially insects. Possible methods for controlling of P. aeratus are suggested as main output of the study.

Coniferous forests in Europe have a considerable number of pests that attack trees of all ages from youngest up to oldest ones. One of them is the large pine weevil Hylobius abietis. This species is widespread in Europe and occurs from warm southern areas (Spain) up to northern countries (Sweden, Finland). Larvae of this species do not cause damage, they help in the decomposition process of stumps and roots. Adults are harmful as they consume bark of young coniferous seedlings, above all of spruce and pine. One adult can consume on average 75 mm2 of bark per day. Individuals can live up to 4 years, and during their lives they can damage and kill several tens of coniferous seedlings. Traditional chemical protection of seedlings against this pest is and will gradually be more and more restricted or forbidden. In this review, we describe this method as well as all other alternative methods including biological protection. We estimate that H. abietis causes annual damages in Europe of almost 120 million € and damages several tens of thousands of hectares of young forest stands.

The gypsy moth is one of the most serious pests in forests and fruit tree plantations over prevailing parts of the Northern Hemisphere. This work is based on a literature review, and presents history of gypsy moth Lymantria dispar L., observed in Slovak forests within the period 1945–2020. The life cycle, hosts, natural enemies, population dynamics of pests, impact of outbreaks on forests and different management methods used in the past are discussed. Since 1945, there were nine gypsy moth outbreaks in Slovakia. Between 1945 and 2020, a total of 155,034 ha of deciduous forests were touched with varying intensity, representing an average annual damage of 2,040 ha. The strongest outbreak culminated in 2004. Totally 51,479 ha were attacked in the period of 2000–2008. We have found outbreak periods that repeat with frequency of 7.8 ±2.2 years and the average outbreak phase lasts 3.1 ±1.1 years. The period between two subsequent outbreaks seems to be more or less constant and duration of the outbreak phase seems to be gradually shortened during the study period. Several factors influencing the gypsy moth population dynamics in Slovakia are discussed. The role of biological control by using entomopathogenic fungus Entomophaga maimaiga is described.

Introduction: As a result of climate change and bark beetle outbreaks in forests, extensive salvage, and sanitary cutting have been undertaken in Europe, resulting in many clear-cuts with coarse stumps. The populations of pine weevils (Hylobius abietis and Hylobius pinastri) are steadily increasing. A high abundance of pine weevils feeding on seedlings typically results in significant economic losses and prolongs the forest establishment period. However, information on these species spatial distribution and habitat selection patterns, necessary for assessing their harmfulness and subsequently accurately estimating their threat to reforested areas, is lacking. To determine which factors influence spatial selection patterns and seedling type preference, this study investigated which clear-cut factors increase pine weevil abundance and which seedling types (species and age) are the most preferred. Methods: The experiment was carried out on 20 clear-cuts in the central Czech Republic. We evaluated soil moisture level, average stump distance and diameter, proportion of other conifers, and whether the stumps were mulched. We detected the abundance of pine weevils using pitfall traps. We determined the feeding scar intensity on the first 10 cm of seedling stems on commonly used seedlings for reforestation in central Europe: 1-year-old Scots pine (Pinus sylvestris), European larch (Larix decidua), and 3-year-old Norway spruce (Picea abies), with 1,200 seedlings in total. The individual seedling types alternated in rows. The results were evaluated using generalized linear mixed-effect models (GLMMs). As dependent variables we used total numbers of H. abietis and H. pinastri. The soil moisture level, mulching, proportion of other conifers, average stump diameter, and distance were considered independent variables. Results: We found that Norway spruce was the least attractive to pine weevils. We found a higher abundance of H. abietis females in moist clear-cuts, confirming that dry clear-cuts are less suitable for oviposition. Conclusion: According to our findings, if foresters want to plant coniferous seedlings, it seems that planting older spruce is a better option than planting larch and pine. These findings provide valuable insights for forest management and reforestation strategies, equipping foresters with the knowledge to mitigate the threat of pine weevils and ensure successful forest establishment. [ABSTRACT FROM AUTHOR]

Phloeosinus aubei is invasive in Central Europe, spreading northward from the Mediterranean region because of climate change. P. aubei has the potential to become a pest of mature, naturally occurring juniper trees (Juniperus communis) in protected areas, as well as junipers, thujas and cypresses in nurseries and urban environments. In 2020 and 2021, we conducted two experiments to compare various lures for trapping P. aubei. In the first experiment, we compared four lures: α‐pinene; turpentine; a mixture of cade oil, juniper berry oil and ethanol; and a juniper branch (8–10 cm long, 3–5 cm wide) deployed with ethanol. In the second experiment, we compared Hostowit® with a juniper branch (8–10 cm long, 3–5 cm wide) deployed with ethanol. In both experiments, juniper branches deployed with ethanol attracted a greater number of P. aubei beetles compared to the other lures. In total, we captured 1056 individuals belonging to 36 species of Scolytinae. Among the most abundant species, Xyleborinus saxesenii, Xyleborus monographus and Anisandrus dispar were lured by ethanol in combination with other substances or deployed with juniper branches. Xyleborus dryographus showed a positive association with turpentine. Ips typographus was positively associated with α‐pinene, while Orthotomicus laricis, Hylastes attenuatus and Gnathotrichus materiarius were positively associated with Hostowit® lure. [ABSTRACT FROM AUTHOR]

Panolis flammea is an important pest whose populations intermittently outbreak in Europe. The species overwinters as pharate moths in the pupal stage in soil.Details on the metabolic activity and cold hardiness of P. flammea during the overwintering period have not been published. Therefore, we assessed O2 consumption and the supercooling point (SCP) of P. flammea in late November, mid‐February, and mid‐March and the influence of soil humidity under fluctuating temperatures and with brief exposures to two increased temperature regimes (10 and 20°C).The respiration pattern indicated diapause termination in mid‐February. A threshold of 0.169 μl O2 h−1 mg−1 fresh weight indicated potentially activated pre‐emerging moths. Drought increased respiration rates.The SCP was lowest in mid‐February (−22.2°C) and was negatively correlated with pupal mass. The frost tolerance tended to increase with low substrate humidity, especially at the end of the overwintering period.Our results indicate that P. flammea requires more energy during dry and mild winters than in wet and cold winters. Winter diapause termination and post‐diapause development may therefore be accelerated as environmental warming and drought increase. [ABSTRACT FROM AUTHOR]