Influence of selected factors on bark beetle outbreak dynamics in the Western Carpathians

Abstract In the period from 1992 to 2013, more than 3.8 million m3 of spruce wood from an area of 55 thousand ha of forests in the Kysuce region (Western Carpathians) was affected by bark beetles. This region has had the highest volume of salvage fellings in Slovakia. While before 1991, bark-beetle outbreak usually occurred after snow and wind disturbances, since 1992 they have occurred in the years with extremely warm and dry growing seasons and the years following them. These years were also characterised by high volumes of wood affected by honey fungus (Armillaria spp.), which only rarely took part in the calamities before 1992. Extreme deterioration of the situation occurred after 2003. In fragmented and sparse stands, the volume of wood damaged by wind increased. Artificial origin of spruce stands, their high occurrence, high age and even-agedness are likely pre-disposing factors of spruce forest decline. Bark beetles have become the most important factor of spruce decline. The most important factors driving the bark beetle attack on forest stands in the period 1973–2013 were the amount of unprocessed wood in the previous year; the amount of wood affected by honey fungus, precipitation total, and average temperature in the current growing season. Another important factor that complicated the situation was also the inferior quality of forest management.

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Efficiency of Harvester with the Debarking Head at Logging in Spruce Stands Affected by Bark Beetle Outbreak

Forests ◽

10.3390/f12101348 ◽

2021 ◽

Vol 12 (10) ◽

pp. 1348

Author(s):

Václav Mergl ◽

Tomáš Zemánek ◽

Marian Šušnjar ◽

Jan Klepárník

Keyword(s):

Moisture Content ◽

Bark Beetle ◽

Growing Season ◽

Time Study ◽

Trunk Diameter ◽

Spruce Stands

This paper deals with the use of debarking modifications of the conventional harvester head in the conditions of felling due to bark beetle calamity. For this purpose, a time study was established, in which the conventional heads were compared with the heads with debarking modifications on four research plots and two harvesters. The measurements were taken from August to September 2018. Harvester efficiency with the use of the head with the debarking configuration ranged from 41.2% to 41.8% from the efficiency of a machine with the conventional head, depending on the felling type. It was also demonstrated that the quality of debarking does not depend on the trunk moisture content in the growing season. In terms of diameter, it was found that the best debarked parts of the stem were those occurring in its middle. Specifically, in the central part of the stem with a diameter of 13 to 23 cm, 91.0% of the stem area was debarked in the main felling and 76.6% in the thinning. In contrast, the top parts of the stem (trunk diameter up to 13 cm) were the least debarked. In the main felling, it was 74.2% of the stem area and in the thinning, only 52.2%.

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An attempt to use the fungus Beauveria bassiana (Bals.) Vuill. in forest protection against the bark beetle Ips typographus (L.) in the field

Forest Research Papers ◽

10.1515/frp-2015-0001 ◽

2015 ◽

Vol 76 (1) ◽

pp. 5-17 ◽

Cited By ~ 4

Author(s):

Wojciech Grodzki ◽

Mieczysław Kosibowicz

Keyword(s):

Beauveria Bassiana ◽

Bark Beetle ◽

Bark Beetles ◽

Tree Mortality ◽

Ips Typographus ◽

Forest Environment ◽

Forest Protection ◽

Spruce Stands ◽

Insect Populations ◽

Fungus Beauveria Bassiana

Abstract In 2011-2013, trials on the use of the entomopathogenic fungus Beauveria bassiana against bark beetle (Ips typographus) populations were carried out under open field conditions in Norway spruce stands suffering from an outbreak in the Beskid Żywiecki Mts. in Poland. Modified pheromone traps were deployed to capture and thereafter release fungus-infected bark beetles to the forest environment. Infested spruce trees felled next to the traps remained unaffected by the transmission of the fungus to insect populations. Direct spraying or dusting of lying trap logs and suspended caged rearing bolts did not have any effect on spruce infestation by I. typographus, its reproduction success and development or natural enemies inside the bark. A very small effect on mortality rates of target as well as non-target insects overwintering in the dusted litter was observed. Treated stands, unlike control stands, were indirectly affected by the treatment, evidenced by the reduction of tree mortality due to bark beetle infestation. At present, no recommendations concerning the potential use of the fungus in forest protection can be given. However such an environmentally friendly approach represents a promising future prospect.

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Bioecological peculiarities and economic significance of large fruit bark beetle (Scolytus mali Bechstein, 1805) and fig bark beetle (Hypoborus ficus Erichson, 1836) in the southern slopes of the Great Caucasus (Azerbaijan)

Studia Biologica ◽

10.30970/sbi.1501.641 ◽

2021 ◽

Vol 15 (1) ◽

pp. 61-66

Author(s):

K. B. Isayeva ◽

Keyword(s):

Bark Beetle ◽

Bark Beetles ◽

Fruit Trees ◽

Study Region ◽

Vegetative Organs ◽

Greater Caucasus ◽

Economic Significance ◽

Host Trees ◽

Large Numbers

Background. Bark beetles (Coleoptera, Curculionidae, Scolytinae) are major pests of wood-fruit trees, and infestations often accelerate tree death. Bark beetles are insects that are closely related to their host trees. According to the type of feeding they belong to xylophages [7]. They prefer weakened, sick or damaged trees. Thus, bark beeteles can more easily penetrate into trees affected by various natural phenomena (wind, storm, rain) or primary pests. They are hardly ever found in rotting trees. The research was carried out on the southern slopes of the Great Caucasus during the period 2013–2016. The great difference in the altitude in the study area results in a variety of natural conditions. This, in turn, leads to the richess of fauna and flora of the area. Thus, valuable fruit trees grow both in the forests and fruit farms of the study region. However, large numbers of fruit trees are attacked by bark beetles every year, which negatively affects the numbers and the quality of trees. Untimely processing of the trees leads to their drying and destruction. According to modern systematics, bark beetles belong to the Scolytinae (Latreille, 1804) subfamily of the Curculionidae (Latreille, 1802) family. There are about 6,000 species of bark beetles from 28 triba and 230 genera in the world [8]. These insects also cause serious damage in countries neighboring of Azerbaijan [1, 2, 9, 11 ]. Despite the fact that bark beetles are of great agricultural importance, they are not sufficiently studied in Azerbaijan. Materials and Methods.The material for research was collected and treated according to common entomological methods. The vegetative organs of various trees were cut and dissected to detect adult beetles, eggs and larvae of bark beetles. Identification of bark beetles was carried out according to keys. MBS-9 microscope was used to determine the morphological features of beetles. Results. As a results of the research, we analyzed 241 samples (237 adults and 4 pupae) of bark beetles collected in 7 districts of the southern slopes of the Greater Caucasus, of which 54 specimens belonged to Scolytus mali and 187 to Hypoborus ficus. Conclusion. Out of 30 species of bark beetles detected on the southern slopes of the Greater Caucasus, 7 ones (Scolytus mali Bechst., S. amygdali Guer., S. fasciatus Rtt., S. rugulosus Ratz., Hypoborus ficus Er., Xyleborus dispar F., X. saxeseni Ratz.) were determined as fruit trees pests. Two of them (Scolytus mali and Hypoborus ficus) are widely distributed in the area and cause serious damage to fruit trees.

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Effect of mature spruce forest on canopy interception in subalpine conditions during three growing seasons

Journal of Hydrology and Hydromechanics ◽

10.2478/johh-2021-0025 ◽

2021 ◽

Vol 69 (4) ◽

pp. 436-446

Author(s):

Martin Jančo ◽

Pavel Mezei ◽

Andrej Kvas ◽

Michal Danko ◽

Patrik Sleziak ◽

...

Keyword(s):

Growing Season ◽

Canopy Gap ◽

Synoptic Situation ◽

Spruce Forest ◽

Canopy Interception ◽

Growing Seasons ◽

The North ◽

Precipitation Total ◽

Normal Period ◽

Spruce Stands

Abstract The interception process in subalpine Norway spruce stands plays an important role in the distribution of throughfall. The natural mountain spruce forest where our measurements of throughfall and gross precipitation were carried out, is located on the tree line at an elevation of 1,420 m a.s.l. in the Western Tatra Mountains (Slovakia, Central Europe). This paper presents an evaluation of the interception process in a natural mature spruce stand during the growing season from May to October in 2018–2020. We also analyzed the daily precipitation events within each growing season and assigned to them individual synoptic types. The amount and distribution of precipitation during the growing season plays an important role in the precipitation-interception process, which confirming the evaluation of individual synoptic situations. During the monitored growing seasons, precipitation was normal (2018), sub-normal (2019) and above-normal (2020) in comparison with long-term precipitation (1988–2017). We recorded the highest precipitation in the normal and above-normal precipitation years during the north-eastern cyclonic synoptic situation (NEc). During these two periods, interception showed the lowest values in the dripping zone at the crown periphery, while in the precipitation sub-normal period (2019), the lowest interception was reached by the canopy gap. In the central crown zone near the stem, interception reached the highest value in each growing season. In the evaluated vegetation periods, interception reached values in the range of 19.6–24.1% of gross precipitation total in the canopy gap, 8.3–22.2% in the dripping zone at the crown periphery and 45.7–51.6% in the central crown zone near the stem. These regimes are expected to change in the Western Tatra Mts., as they have been affected by windstorms and insect outbreaks in recent decades. Under disturbance regimes, changes in interception as well as vegetation, at least for some period of time, are unavoidable.

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Contrasting development of declining and living larch-spruce stands after a disturbance event: A case study from the High Tatra Mts.

Forestry Journal ◽

10.1515/forj-2015-0024 ◽

2015 ◽

Vol 61 (3) ◽

pp. 157-166 ◽

Cited By ~ 3

Author(s):

Vladimír Šebeň ◽

Bohdan Konôpka ◽

Michal Bošeľa ◽

Jozef Pajtík

Keyword(s):

Carbon Sequestration ◽

Bark Beetle ◽

Tree Species ◽

Bark Beetles ◽

Spruce Forests ◽

Pioneer Tree Species ◽

Pioneer Tree ◽

Spruce Stands ◽

The High Tatras

AbstractThe decline of spruce stands caused by bark beetle outbreaks is a serious economic and ecological problem of forestry in Slovakia. In the preceding period, the decline affected mainly secondary spruce forests. Over the last decade, due to large bark-beetle outbreaks this problem has been observed also in natural spruce forests, even at high elevations. We dealt with this issue in a case study of short-term development of larch-spruce stands in the High Tatras (at a site called Štart). We compared the situation in the stand infested by bark beetles several years after the wind-throw in 2004 with the stand unaffected by bark beetles. We separately analysed the development of the mature (parent) stands and the regeneration. The results indicated that forest decline caused by bark beetles significantly depended on the stand structure (mainly tree species composition), which affected the period of stand disintegration. Mortality of spruce trees slowed down biomass accumulation (and thus carbon sequestration) in the forest ecosystem. In the new stand, pioneer tree species dominated (in the conditions of the High Tatras it is primarily rowan), although their share in the parent stand was negligible. The results showed different trends in the accumulation of below-ground and above-ground biomass in the declined and living stands. In the first years after the stand decline, rowan accumulated significantly more biomass than the main tree species, i.e. spruce. The reverse situation was under the surviving stand, where spruce trees accumulated more biomass than rowan. The different share of spruce and pioneer tree species, mainly rowan, affected the ratio between fixed (in woody parts of trees) and rotating (in foliage) carbon in the undergrowth. Forest die-back is a big source of carbon emissions from dead individuals, and the compensation of these losses in the form of carbon sequestration by future stands is a matter of several decades.

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Economic Analysis of a Transport Company in the Aspect of Car Vehicle Operation

Sustainability ◽

10.3390/su13010427 ◽

2021 ◽

Vol 13 (1) ◽

pp. 427

Author(s):

Magdalena Rykała ◽

Łukasz Rykała

Keyword(s):

Weather Conditions ◽

Neural Model ◽

Motor Vehicles ◽

Bulk Materials ◽

The Sustainable Development ◽

Average Temperature ◽

Transport Services ◽

Vehicle Operation ◽

The Impact

The article describes the issues of transport of bulk materials. The knowledge of this process has a key impact on the rational planning of transport tasks. It is necessary to have knowledge about the transport services market and the competition that exists in it. In order to achieve a competitive advantage on the market, enterprises should analyze data on the implementation of transport tasks on an ongoing basis. It is also important that the costs incurred from the conducted activity are minimized, while increasing the quality of services and taking into account the sustainable development of the enterprise. The study analyzes data from a few selected motor vehicles in the period of 3 years of operation, coming from an enterprise specializing in the transport of bulk materials. Moreover, a global sensitivity analysis was performed based on a neural model describing the impact of the analyzed factors on the company’s profit. The results show that the most important factors influencing the company’s profit are the fuel consumption of individual vehicles, the driver (driving style) and the month (average temperature, weather conditions).

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Drivers of Spruce Bark Beetle (Ips typographus) Infestations on Downed Trees after Severe Windthrow

Forests ◽

10.3390/f11121290 ◽

2020 ◽

Vol 11 (12) ◽

pp. 1290

Author(s):

Branislav Hroššo ◽

Pavel Mezei ◽

Mária Potterf ◽

Andrej Majdák ◽

Miroslav Blaženec ◽

...

Keyword(s):

Solar Radiation ◽

Bark Beetle ◽

Bark Beetles ◽

Ips Typographus ◽

Wind Damage ◽

Stem Length ◽

Local Conditions ◽

Spruce Bark Beetle ◽

Management Actions ◽

Spruce Bark

Research Highlights: Bark beetles are important agents of disturbance regimes in temperate forests, and specifically in a connected wind-bark beetle disturbance system. Large-scale windthrows trigger population growth of the European spruce bark beetle (Ips typographus L.) from endemic to epidemic levels, thereby allowing the killing of Norway spruce trees over several consecutive years. Background and Objectives: There is a lack of evidence to differentiate how outbreaks are promoted by the effects of environmental variables versus beetle preferences of trees from endemic to outbreak. However, little is known about how individual downed-tree characteristics and local conditions such as tree orientation and solar radiation affect beetle colonization of downed trees. Materials and Methods: To answer this question, we investigated the infestation rates and determined tree death categories (uprooted, broken, and stump) in wind-damaged areas in Western Tatra Mts. in Carpathians (Slovakia) from 2014–2016, following a windthrow in May 2014. In total, we investigated 225 trees over eight transects. For every tree, we measured its morphological (tree height, crown characteristics), environmental (solar radiation, terrain conditions, trunk zenith), temporal (time since wind damage), and beetle infestation (presence, location of attack, bark desiccation) parameters. We applied Generalized Additive Mixed Models (GAMM) to unravel the main drivers of I. typographus infestations. Results: Over the first year, beetles preferred to attack broken trees and sun-exposed trunk sides over uprooted trees; the infestation on shaded sides started in the second year along with the infestation of uprooted trees with lower desiccation rates. We found that time since wind damage, stem length, and incident solar radiation increased the probability of beetle infestation, although both solar radiation and trunk zenith exhibited nonlinear variability. Our novel variable trunk zenith appeared to be an important predictor of bark beetle infestation probability. We conclude that trunk zenith as a simple measure defining the position of downed trees over the terrain can anticipate beetle infestation. Conclusions: Our findings contribute to understanding of the bark beetle’s preferences to colonize windthrown trees in the initial years after the primary wind damage. Further, our findings can help to identify trees that are most susceptible to beetle infestation and to prioritize management actions to control beetle population while maintaining biodiversity.

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INFESTATION OF CERATOCYSTIS WAGENERI-INFECTED PONDEROSA PINES BY BARK BEETLES (COLEOPTERA: SCOLYTIDAE) IN THE CENTRAL SIERRA NEVADA

The Canadian Entomologist ◽

10.4039/ent112725-7 ◽

1980 ◽

Vol 112 (7) ◽

pp. 725-730 ◽

Cited By ~ 14

Author(s):

D. J. Goheen ◽

F. W. Cobb

Keyword(s):

Sierra Nevada ◽

Bark Beetle ◽

Ponderosa Pine ◽

Bark Beetles ◽

Dendroctonus Brevicomis ◽

Disease Category ◽

The Relationship ◽

Periodic Examination ◽

Apparently Healthy

AbstractThe relationship between bark beetle infestation of ponderosa pine and severity of infection by Ceratocystis wageneri was investigated by closely monitoring 256 trees (136 apparently healthy, 60 moderately diseased, and 60 severely diseased at initiation of study) for beetle infestation from summer 1972 to fall 1975. Disease ratings were updated by periodic examination, and some trees changed disease category during the study. Ninety trees were infested by Dendroctonus brevicomis, D. ponderosae, or both, five by buprestids alone, and one tree died from effects of the pathogen alone. Sixty-two of the beetle-infested trees were severely diseased at time of infestation, 25 were moderately diseased, and only three were apparently healthy. Thus, the results showed that bark beetles were much more likely to infest infected than healthy trees. Among diseased trees, those with advanced infections were most likely to be infested. There was evidence that buprestids (especially Melanophila spp.) and possibly Ips spp. attacked diseased trees prior to Dendroctonus spp. infestation.

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ATTRACTION OF HYLOBIUS PALES (HERBST) (COLEOPTERA: CURCULIONIDAE) TO PHEROMONES OF BARK BEETLES (COLEOPTERA: SCOLYTIDAE)

The Canadian Entomologist ◽

10.4039/ent122423-5 ◽

1990 ◽

Vol 122 (3) ◽

pp. 423-427 ◽

Cited By ~ 5

Author(s):

Thomas W. Phillips

Keyword(s):

Field Experiment ◽

Bark Beetle ◽

Bark Beetles ◽

Suitable Host ◽

Male And Female ◽

Pine Weevil ◽

Ips Calligraphus ◽

Hylobius Pales ◽

Host Resource

AbstractResults of a field experiment indicate that adults of the pine weevil Hylobius pales (Herbst) respond to pheromones of bark beetles. Each sex of H. pales was more attracted to traps baited with the combination of a pine bolt infested with male Ips calligraphus Germar plus the synthetic Dendroctonus Erichson pheromones frontalin and exo-brevicomin, than to traps baited with pine bolts alone. The combined numbers of male and female H. pales caught in traps baited only with Ips calligraphus-infested bolts were significantly greater than numbers caught in traps baited with uninfested control bolts. The attraction of H. pales to bark beetle pheromones may represent a kairomonal response in which weevils exploit semiochemicals from other species that signify a suitable host resource.

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Impacts of European spruce bark beetle infestations on Norway spruce BVOC emissions

10.5194/egusphere-egu21-7624 ◽

2021 ◽

Author(s):

Erica Jaakkola ◽

Anna Maria Jönsson ◽

Per-Ola Olsson ◽

Maj-Lena Linderson ◽

Thomas Holst

Keyword(s):

Climate Change ◽

Drought Stress ◽

Norway Spruce ◽

Bark Beetle ◽

Bark Beetles ◽

Atmospheric Environment ◽

Strong Increase ◽

Healthy Tree ◽

Spruce Bark Beetle ◽

Spruce Bark

Tree killing by spruce bark beetles (Ips typographus) is one of the main disturbances to Norway spruce (Picea abies) forests in Europe and the risk of outbreaks is amplified by climate change with effects such as increased risk of storm felling, tree drought stress and an additional generation of spruce bark beetles per year[1]. The warm and dry&#160;summer of&#160;2018 triggered large outbreaks in Sweden, the increased outbreaks are still ongoing and affected&#160;about 8 million m3&#160;forest&#160;in 2020[2]. This is the so&#160;far highest record of trees killed by the spruce bark beetle in a single year in Sweden[2]. In&#160;1990-2010,&#160;the spruce bark beetle killed on&#160;average&#160;150 000 m3&#160;forest per year in southern Sweden[3]. Bark beetles normally seek and attack Norway spruces with lowered defense, i.e. trees that are wind-felled or experience prolonged drought stress[4]. However, as the number of bark beetle outbreaks increase, the risk of attacks on healthy trees also increase[5]. This causes a higher threat to forest industry, and lowers the possibilities to mitigate climate change in terms of potential decreases in carbon uptake if the forests die[4,5]. Norway spruce trees normally defend themselves by drenching the beetles in resin[6]. The resin in turn contains different biogenic volatile organic compounds (BVOCs), which can vary if the spruce is attacked by bark beetles or not [4,6]. The most abundant group of terpenoids (isoprene, monoterpenes and sesquiterpenes), is most commonly emitted from conifers, such as Norway spruce[7,8]. The aim of this study was to enable a better understanding of the direct defense mechanisms of spruce trees by&#160;quantifying BVOC emissions and its composition&#160;from individual&#160;trees under attackTo analyze the bark beetles&#8217; impact on Norway spruce trees a method was developed using tree trunk chambers and adsorbent tubes. This enables direct measurements of the production of BVOCs from individual trees. Three different sites in Sweden, with different environmental conditions were used for the study and samples were collected throughout the growing season of 2019. After sampling, the tubes were analyzed in a lab using automated thermal desorption coupled to a gas chromatograph and a mass spectrometer to identify BVOC species and their quantity.The preliminary results show a strong increase in BVOC emissions from a healthy tree that became infested during the data collection. The finalized results expect to enable better understanding of how spruce trees are affected by insect stress from bark beetles, and if bark beetle infestation will potentially result in increased carbon emission in the form of BVOCs.References[1] J&#246;nsson et al. (2012). Agricultural and Forest Meteorology 166: 188&#8211;200 [2] Skogsstyrelsen, (2020). https://via.tt.se/pressmeddelande/miljontals-granar-dodades-av-granbarkborren-2020?publisherId=415163&releaseId=3288473 [3] Marini et al. (2017). Ecography, 40(12), 1426&#8211;1435. [4] Raffa (1991). Photochemical induction by herbivores. pp. 245-276 [5] Seidl, et al. (2014). Nature Climate Change,&#160;4(9), 806-810. [6] Ghimire, et al. (2016).&#160;Atmospheric Environment,&#160;126, 145-152. [7] Niinemets, U. and Monson, R. (2013). ISBN 978-94-007-6606-8 [8] Kesselmeier, J. and Staudt, M. (1999). Journal of Atmospheric Chemistry, 33(1), pp.23-88

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