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Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Of the more than five hundred and fifty species of North American bark beetles (Coleoptera: Curculionidae, Scolytinae), approximately twenty species occasionally cause large amounts of tree mortality in conifer forests. During 2000–2020, trends in bark beetle impacts changed dramatically across North America compared to those observed during the mid- to late 20th century. We review tools and tactics available for bark beetle suppression and prevention and provide an overview of temporal and spatial trends in bark beetle impacts in North American forests during 2000–2020. Higher impacts were observed for several bark beetle species in western North America accompanied by substantial declines in eastern North America driven by large reductions in southern pine beetle (Dendroctonus frontalis) activity in the southeastern United States. Regional differences likely result from a higher species richness of both bark beetles and their hosts in western North America, stronger direct and indirect effects of climate change (warming and drying) on bark beetles in western North America, and differences in forest composition, management history, and other abiotic stressors and disturbances. Study Implications Compared to the mid- to late 20th century, bark beetles have had increased impacts in western North America and reduced impacts in eastern North America, the latter driven by large reductions in southern pine beetle (Dendroctonus frontalis) activity in the southeastern United States. We review tools and tactics available to foresters and other natural resource managers to reduce the negative impacts of bark beetles on forests. Furthermore, we provide several potential explanations for recent trends in bark beetle impacts between eastern and western North America. [ABSTRACT FROM AUTHOR]

Cases of colonization of the narrow-leaved oleaster Elaeagnus angustifolia L., lacking external signs of being weakened, by bark beetles of the genus Scolytus and development of the beetles' offspring are described. The biological specificities of an aggressive xylophage, Scolytus jaroschewskii, and its association with the microorganisms in the foci of forest dieback are also characterized. [ABSTRACT FROM AUTHOR]

A key to and an annotated list of species of the genus Scolytus Geoffroy, 1762 from European Russia are given. [ABSTRACT FROM AUTHOR]

In temperate forests, elevated frequency of drought related disturbances will likely increase the incidence of interactions between disturbances such as bark beetle epidemics and wildfires. Our understanding of the influence of recent drought and insect‐induced tree mortality on wildfire severity has largely lacked information from forests adapted to frequent fire. A recent unprecedented tree mortality event in California's Sierra Nevada provides an opportunity to examine this disturbance interaction in historically frequent‐fire forests. Using field data collected within areas of recent tree mortality that subsequently burned in wildfire, we examined whether and under what conditions wildfire severity relates to severity of prefire tree mortality in Sierra Nevada mixed‐conifer forests. We collected data on 180 plots within the 2015 Rough Fire and 2016 Cedar Fire footprints (California, USA). Our analyses identified prefire tree mortality as influential on all measures of wildfire severity (basal area killed by fire, RdNBR, and canopy torch) on the Cedar Fire, although it was less influential than fire weather (relative humidity). Prefire tree mortality was influential on two of three fire‐severity measures on the Rough Fire, and was the most important predictor of basal area killed by fire; topographic position was influential on two metrics. On the Cedar Fire, the influence of prefire mortality on basal area killed by fire was greater under milder weather conditions. All measures of fire severity increased as prefire mortality increased up to prefire mortality levels of approximately 30–40%; further increases did not result in greater fire severity. The interacting disturbances shifted a pine‐dominated system (Rough Fire) to a cedar–pine–fir system, while the pre‐disturbance fir–cedar system (Cedar Fire) saw its dominant species unchanged. Managers of historically frequent‐fire forests will benefit from utilizing this information when prioritizing fuels reduction treatments in areas of recent tree mortality, as it is the first empirical study to document a relationship between prefire mortality and subsequent wildfire severity in these systems. This study contributes to a growing body of evidence that the influence of prefire tree mortality on wildfire severity in temperate coniferous forests may depend on other conditions capable of driving extreme wildfire behavior, such as weather. [ABSTRACT FROM AUTHOR]

The population dynamics of the maple bark beetle Scolytus koenigi Schevyrew, 1890 in oak groves of the forest-steppe zone of European Russia is described based on the data obtained in forest plots of the Tellerman forest field station, damaged by creeping fires and xylotrophic fungi. [ABSTRACT FROM AUTHOR]

Highlights • Host and its environment are important for monitoring Scolytus intricatus. • Branch diameter affects the number of S. intricatus entrance and emergence holes. • Host tree diameter affects the number of entrance holes. • Canopy openness in spring affects the abundance and body size of S. intricatus. • Big oak trees with thick branches overgrown by conifers are at highest risk of S. intricatus infestation. Abstract Urban forests are important for the health of cities. These forests face high anthropogenic pressure, including demands on their multi-functional role. Therefore, the impact of pests-induced disturbances may be greater for urban forests than forests outside of cities. Monitoring of pests in their native environment is an important tool for the management of urban forests. To better understand how pest population density is affected by the forest environment, we used the Oak bark beetle, Scolytus intricatus , as a model organism. The study was carried out in 2014–2015 in the urban forests of Pardubice City, Czech Republic. Pest population density was studied at three levels: branch, tree and patch. The increasing branch diameter was identified as an important variable with a threshold of 70 mm for entrance holes and 45 mm for emergence holes. Increasing host tree diameter at breast height with a threshold of 46.8 cm was statistically significant at the tree level in terms of the number of entrance holes. Increasing spring canopy openness was identified as an important variable at the patch level with a threshold of 50.78% and had a decreasing trend for the number of reared adults and their total body size. Big oak trees with thick branches under closed spring canopy are the most susceptible to attack by S. intricatus. Based on our findings, we propose that the maintenance of mature oaks under open canopies is important for urban forest management. Avoiding mixed plantings of oaks and conifers should promote these open canopies and lead to multiple advantages regarding oak silviculture. [ABSTRACT FROM AUTHOR]

Three parasitaphelenchid species, Parasitaphelenchus frontalis n. sp., P. costati n. sp. and Bursaphelenchus hirsutae n. sp., are described. Parasitaphelenchus frontalis n. sp. was isolated from the body cavity of Scolytus frontalis emerging from dead logs of Zelkova serrata collected from Kanagawa, Japan, and characterised by its four-lined lateral field in the adults and dome-shaped lip region of the parasitic juveniles. Whereas the two first-mentioned species were isolated from Alniphagus costatus , B. hirsutae n. sp. emerged from dead logs of Alnus hirsuta collected from Nagano, Japan. Parasitaphelenchus costati n. sp. and B. hirsutae n. sp. were recovered from the body cavity and the underside of the elytra of their host/carrier beetle, respectively. Parasitaphelenchus costati n. sp. is characterised by its three-lined lateral field in adults and the presence of a ventrally-directed hook on the lip region of the parasitic juvenile. Bursaphelenchus hirsutae n. sp. belongs to the eggersi group of the genus and is characterised by its three-lined lateral field, dorsally truncate condylus and pointed rostrum of males, and long, smoothly tapering and strongly ventrally recurved, female tail. Molecular characterisation is provided for all three new species and their phylogenys discussed. [ABSTRACT FROM AUTHOR]

New morphological, molecular and bionomic data are added to update the description of Bursaphelenchus eucarpus. The nematode was isolated from larval galleries and adults of the apple bark beetle, Scolytus mali , and the shothole borer, S. rugulosus , present under the bark of the bird cherry, Prunus padus , and the common European plum, P. domestica , in Poland. Detailed male, female and dispersal juvenile morphology and morphometrics are documented and compared with the original description. From partial 18S, ITS1/2 and partial 28S D2-D3 sequences and morphological features (three lateral lines, position of caudal papillae, shape of the delicate spicules with dorsally bent condylus, lack of vulval flap, a long post-uterine branch and a hyaline region at the female tail tip) it can be concluded that B. eucarpus belongs to the eremus group of Bursaphelenchus. The differentiation from related species of the eremus group is discussed. [ABSTRACT FROM AUTHOR]

Dutch elm disease ( DED), caused by the fungi Ophiostoma ulmi and O. novo-ulmi, has reduced elm populations severely in Europe and North America. Breeding programmes are in action to find less susceptible elm varieties suitable for re-establishing elm stands. Bark beetles, mainly Scolytus spp., are the only known natural vectors of DED. During twig feeding, beetles transfer Ophiostoma spores to healthy elms. Thus, less palatable elms should run a lower risk of DED infections. In feeding preference bioassays, we offered twigs from elms exhibiting different degree of susceptibility to O. novo-ulmi, together with non-host trees to Scolytus beetles. Scolytus multistriatus preferred wych elm, Ulmus glabra, to 100% in two-choice tests, whereas S. laevis did not discriminate between a tolerant and a susceptible variety of field elm, U. minor. We suggest that the feeding assay is useful as a low-tech method in breeding programmes for evaluating the suitability of promising elm genotypes to vector insects. [ABSTRACT FROM AUTHOR]

During 2014 and 2015, four species of bark beetles (Coleoptera: Curculionidae: Scolytinae), belonging to a single genus Scolytus Geoffroy, 1762, were collected from elm trees in East Azarbaijan province, northwestern Iran. They were Scolytus pygmaeus (Fabricius, 1787), Scolytus ensifer Eichhoff, 1881, Scolytus ecksteini Butovitsch, 1929, and Scolytus kirschii fasciatus Reitter, 1890. All of them represent new records for East Azarbaijan province. [ABSTRACT FROM AUTHOR]

The forests of the northern Rocky Mountains are hosts of nine species of Nearctic conifer-infesting bark beetles of the genus Scolytus Geoffroy. One of these, Scolytus piceae Swaine (Coleoptera: Curculionidae), infests spruces across the continent including Picea engelmannii Parry (Pinaceae) in Idaho. Mature larvae overwintered before transforming to adults, which infested new hosts in early June. Scolytus piceae most commonly infested shaded out lower branches of mature live spruce. In sporadic wind-felled spruce, the beetle infested the terminal portion of branches throughout the crown, whereas another Scolytinae, Polygraphus rufipennis (Kirby), infested the thicker bark basal portion of the same branches. This niche separation resulted from difference in time of their dispersal flight and ability of S. piceae to colonize thin bark by engraving the underlying sapwood. Population recruitment of S. piceae was low in shaded out lower branches, in balance with this limited host resource. Features of the head of S. piceae larvae differed from that reported in literature, including the mandible dentition, antennal field, and pattern of setae on the postlabium. [ABSTRACT FROM AUTHOR]

The authors report on the presence of species of the family Tarsonemidae in association with three bark beetle species (Orthotomicus erosus (Wollaston, 1857), Scolytus scolytus (Fabricius, 1775), and S. multistriatus (Marsham, 1802)) in two provinces in Central and Northern Iran. The following mite species are new for the fauna of Iran: Heterotarsonemus hajekae Smiley and Moser, 1985, H. magowskii Khaustov, 2001, and Tarsonemus crassus (Schaarschmidt, 1959). The genus Heterotarsonemus is newly recorded in Asia. The new record of H. hajekae is the second ever known in the world and H. magowskii is now established as new phoront of the bark beetle host O. erosus. Tarsonemus crassus is recorded outside the Europe for the first time. The taxonomy, identification, relationships with beetle hosts, and biogeography of the newly recorded mite species are briefly discussed. [ABSTRACT FROM AUTHOR]

Three yeast strains designated as S44, XF1 and XF2, respectively, were isolated from Scolytus scheryrewi Semenov of apricot tree in Shule County, Xinjiang, China, and were demonstrated to be a new member of the genus Candida by sequence comparisons of 26S rRNA gene D1/D2 domain and internal transcribed spacer (ITS) region. BLASTn alignments on NCBI showed that the similarity of 26S rRNA gene sequences of S44 (type strain) to all sequences of other Candida yeasts was very low (≦93 %). The phylogenetic tree based on the 26S rRNA gene D1/D2 domain and ITS region sequences revealed that the strain S44 is closely related to C. blattae, C. dosseyi, C. pruni, C. asparagi, C. fructus and C. musae. However, the strain S44 is distinguished from these Candida species by the physiological characteristics. Moreover, the strain S44 formed typical pseudohyphae when grown on cornmeal agar at 25 °C for 7 days, but did not form ascospores in sporulation medium for 3-4 weeks. Therefore, the name Candida xinjiangensis is proposed for the novel species, with S44 (=KCTC27747) as the type strain. [ABSTRACT FROM AUTHOR]

Molecular identification is going to be more widespread in taxonomic studies of insects when traditional tools are problematic and time consuming. Identification of bark beetles, as one of the most important pests of forests, based on morphological characteristics is difficult because of their small size and morphological similarities. In the current study, species-specific primers were designed to identify two most abundant and morphologically similar bark beetle species Scolytus ensifer Eichhoff 1881 and S. ecksteini Butovitsch 1929, both found on Ulmus minor Miller in north of Iran. These species-specific primers successfully produced a fragment size with 318 bp and 465 bp of mitochondrial cytochrome oxidase 1 (CO1) gene in S. ensifer and S. ecksteini respectively. The results revealed tha t the multiplex polymerase chain reaction using the species-specific primers could amplify a unique band to distinguish these two species so confirmed this method as a convenient and quick tool to identify those two bark beetle species. [ABSTRACT FROM AUTHOR]

Scolytus amygdali is a polyphagous insect pest that feeds on fruit trees and forest trees. Our study assessed the host preference and reproductive potential of S. amygdali on four tree species: almond (Prunus dulcis), apricot (Prunus armeniaca), peach (Prunus persica), and plum (Prunus domestica). Females of S. amygdali produced maternal galleries that were longer on peach than the other three trees, and female fecundity was highest on peach. Females with longer maternal galleries produced more eggs, indicating a positive correlation between maternal gallery length and female fertility. The under-bark development time of S. amygdali is significantly shorter on plum (45 days) and almond (56 days) than on apricot (65 days) and peach (64 days). Despite this longer development time on peach, our results still suggest that, of the four types of tree tested, peach is the most preferred host for S. amygdali. [ABSTRACT FROM AUTHOR]

Two new multi-proxy records of environmental change are provided from Horton Kirby Paper Mill and Old Seager Distillery in the Lower Thames Valley. Each site has evidence for a decline in elm woodland, which at Horton Kirby Paper Mill is recorded earlier than any other published record from the British Isles: sometime between 7320 and 7240 cal BP. Scolytus scolytus/S. multistriatus (the vectors for Dutch elm disease) are recorded after the decline in both sequences, adding to the number of sites with such evidence in the British Isles. Evidence of paludification and human activity are also recorded at the time of the elm decline reinforcing the multi-causal hypothesis. Integration of these results with 21 palaeoenvironmental records has produced a large number of well-dated, multiproxy records of the elm decline in this part of the UK. On the basis of this dataset, a classification system for categorising the relationships between the causal factors of the elm decline is proposed and recommended for future studies. [ABSTRACT FROM AUTHOR]

The Nearctic bark beetle genus Scolytus Geoffroy was revised based in part on a molecular and morphological phylogeny. Monophyly of the native species was tested using mitochondrial (COI) and nuclear (28S, CAD, ArgK) genes and 43 morphological characters in parsimony and Bayesian phylogenetic analyses. Parsimony analyses of molecular and combined datasets provided mixed results while Bayesian analysis recovered most nodes with posterior probabilities >90%. Native hardwood- and conifer-feeding Scolytus species were recovered as paraphyletic. Native Nearctic species were recovered as paraphyletic with hardwoodfeeding species sister to Palearctic hardwood-feeding species rather than to native conifer-feeding species. The Nearctic conifer-feeding species were monophyletic. Twenty-five species were recognized. Four new synonyms were discovered: S. praeceps LeConte, 1868 (= S. abietis Blackman, 1934; = S. opacus Blackman, 1934), S. reflexus Blackman, 1934 (= S. virgatus Bright, 1972; = S. wickhami Blackman, 1934). Two species were reinstated: S. fiskei Blackman, 1934 and S. silvaticus Bright, 1972. A diagnosis, description, distribution, host records and images were provided for each species and a key is presented to all species. [ABSTRACT FROM AUTHOR]

Mechanical thinning and the application of prescribed fire are commonly used to restore fire-adapted forest ecosystems in the Western United States. During a 10-year period, we monitored the effects of fuel-reduction and forest-restoration treatments on levels of tree mortality in an interior ponderosa pine, Pinus ponderosa Dougl. ex Laws., forest in California. Twelve experimental plots, ranging in size from 77-144 ha, were established to create two distinct forest structural types: mid-seral stage (low structural diversity; LoD) and late-seral stage (high structural diversity; HiD). Following harvesting, half of each plot was treated with prescribed fire (B). A total of 16,473 trees (8.7% of all trees) died during the 10-year period. Mortality was primarily attributed to bark beetles (Coleoptera: Curculionidae, Scolytinae) (10,655 trees), specifically fir engraver, Scolytus ventralis LeConte, mountain pine beetle, Dendroctonus ponderosae Hopkins, western pine beetle, D. brevicomis LeConte, pine engraver, Ips pini (Say), and, to a much lesser extent, Jeffrey pine beetle, D. jeffreyi Hopkins. Trees of all ages and size classes were killed, but mortality was concentrated in the smaller-diameter classes (19-29.2 and 29.3-39.3 cm at 1.37 m in height). Most mortality occurred three to five years following prescribed burns. Higher levels of bark beetle-caused tree mortality were observed on LoD + B (8.7%) than LoD (4.2%). The application of these and other results to the management of interior P. ponderosa forests are discussed, with an emphasis on the maintenance of large trees. [ABSTRACT FROM AUTHOR]

The following species of Curculionoidea are recorded from Canada for the first time, in ten cases also representing new records at the generic level: Ischnopterapion (Ischnopterapion) loti (Kirby, 1808); Stenopterapion meliloti (Kirby, 1808) (both Brentidae); Atrichonotus taeniatulus (Berg, 1881); Barinus cribricollis (LeConte, 1876); Caulophilus dubius (Horn, 1873); Cionus scrophulariae (Linnaeus, 1758); Cryptorhynchus tristis LeConte, 1876; Cylindrocopturus furnissi Buchanan, 1940; Cylindrocopturus quercus (Say, 1832); Desmoglyptus crenatus (LeConte, 1876); Pnigodes setosus LeConte, 1876; Pseudopentarthrum parvicollis (Casey, 1892); Sibariops confinis (LeConte, 1876); Sibariops confusus (Boheman, 1836); Smicronyx griseus LeConte, 1876; Smicronyx lineolatus Casey, 1892; Euwallacea validus (Eichhoff, 1875); Hylocurus rudis (LeConte, 1876); Lymantor alaskanus Wood, 1978; Phloeotribus scabricollis (Hopkins, 1916); Scolytus oregoni Blackman, 1934; Xyleborus celsus Eichhoff, 1868; Xyleborus ferrugineus (Fabricius, 1801); Xylosandrus crassiusculus (Motschulsky, 1866) (all Curculionidae). In addition the following species were recorded for the first time from these provinces and territories: Yukon - Dendroctonus simplex LeConte, 1868; Phloetribus piceae Swaine, 1911 (both Curculionidae); Northwest Territories - Loborhynchapion cyanitinctum (Fall, 1927) (Brentidae); Nunavut - Dendroctonus simplex LeConte, 1868 (Curculionidae); Alberta - Anthonomus tectus LeConte, 1876; Promecotarsus densus Casey, 1892; Dendroctonus ponderosae Hopkins, 1902; Hylastes macer LeConte, 1868; Rhyncolus knowltoni (Thatcher, 1940); Scolytus schevyrewi Semenov Tjan-Shansky, 1902 (all Curculionidae); Saskatchewan - Phloeotribus liminaris (Harris, 1852); Rhyncolus knowltoni (Thatcher, 1940); Scolytus schevyrewi Semenov Tjan-Shansky, 1902 (all Curculionidae); Manitoba - Cosmobaris scolopacea Germar, 1819; Listronotus maculicollis (Kirby, 1837); Listronotus punctiger LeConte, 1876; Scolytus schevyrewi Semenov Tjan-Shansky, 1902; Tyloderma foveolatum (Say, 1832); (all Curculionidae); Ontario - Trichapion nigrum (Herbst, 1797); Nanophyes marmoratus marmoratus (Goeze, 1777) (both Brentidae); Asperosoma echinatum (Fall, 1917); Micracis suturalis LeConte, 1868; Orchestes alni (Linnaeus, 1758); Phloeosinus pini Swaine, 1915; Scolytus schevyrewi Semenov Tjan-Shansky, 1902; Xyleborinus attenuatus (Blandford, 1894) (all Curculionidae); Quebec - Trigonorhinus alternatus (Say, 1826); Trigonorhinus tomentosus tomentosus (Say, 1826) (both Anthribidae); Trichapion nigrum (Herbst, 1797); Trichapion porcatum (Boheman, 1839); Nanophyes marmoratus marmoratus (Goeze, 1777) (all Brentidae); Lissorhoptrus oryzophilus Kuschel, 1952 (Brachyceridae); Acalles carinatus LeConte, 1876; Ampeloglypter ampelopsis (Riley, 1869); Anthonomus rufipes LeConte, 1876; Anthonomus suturalis LeConte, 1824; Ceutorhynchus hamiltoni Dietz, 1896; Curculio pardalis (Chittenden, 1908); Cyrtepistomus castaneus (Roelofs, 1873); Larinus planus (Fabricius, 1792); Mecinus janthinus (Germar, 1821); Microhyus setiger LeConte, 1876; Microplontus campestris (Gyllenhal, 1837); Orchestes alni (Linnaeus, 1758); Otiorhynchus ligustici (Linnaeus, 1758); Rhinusa neta (Germar, 1821); Trichobaris trinotata (Say, 1832); Tychius liljebladi Blatchley, 1916; Xyleborinus attenuatus (Blandford, 1894); Xyleborus affinis Eichhoff, 1868 (all Curculionidae); Sphenophorus incongruus Chittenden, 1905 (Dryophthoridae); New Brunswick - Euparius paganus Gyllenhal, 1833; Allandrus populi Pierce, 1930; Gonotropis dorsalis (Thunberg, 1796); Euxenus punctatus LeConte, 1876 (all Anthribidae); Loborhynchapion cyanitinctum (Fall, 1927) (Brentidae); Pseudanthonomus seriesetosus Dietz, 1891; Curculio sulcatulus (Casey, 1897); Lignyodes bischoffi (Blatchley, 1916); Lignyodes horridulus (Casey, 1892); Dietzella zimmermanni (Gyllenhal, 1837); Parenthis vestitus Dietz, 1896; Pelenomus squamosus Le- Conte, 1876; Psomus armatus Dietz, 1891; Rhyncolus macrops Buchanan, 1946; Magdalis inconspicua Horn, 1873; Magdalis salicis Horn, 1873 (all Curculionidae); Nova Scotia - Dryocoetes autographus (Ratzeburg, 1837); Ips perroti Swaine, 1915; Xyleborinus attenuatus (Blandford, 1894) (all Curculionidae); Prince Edward Island - Dryocoetes caryi Hopkins, 1915 (Curculionidae); Newfoundland - Scolytus piceae (Swaine, 1910) (Curculionidae). Published records of Dendroctonus simplex LeConte, 1868 from Northwest Territories should be reassigned to Nunavut, leaving no documented record for NWT. Collection data are provided for eight provincial and national records published without further information previously. [ABSTRACT FROM AUTHOR]

Dutch Elm Disease ( DED) is a vascular wilt disease of Ulmus species (elms) incited in North America primarily by the exotic fungus Ophiostoma novo-ulmi. The pathogen is transmitted via root grafts and elm bark beetle vectors, including the native North American elm bark beetle, Hylurgopinus rufipes and the exotic smaller European elm bark beetle, Scolytus multistriatus. The banded elm bark beetle, Scolytus schevyrewi, is an exotic Asian bark beetle that is now apparently the dominant elm bark beetle in the Rocky Mountain region of the USA. It is not known if S. schevyrewi will have an equivalent vector competence or if management recommendations need to be updated. Thus the study objectives were to: (i) determine the type and size of wounds made by adult S. schevyrewi on branches of Ulmus americana and (ii) determine if adult S. schevyrewi can transfer the pathogen to American elms during maturation feeding. To determine the DED vectoring capability of S. schevyrewi, newly emerged adults were infested with spores of Ophiostoma novo-ulmi and then placed with either in-vivo or in-vitro branches of American elm trees. The inoculation of trees via feeding wounds was successful 30% of the time for in-vivo trials and 33% for in-vitro trials. Although the infection rate of DED has declined in Colorado over the past 10 years, the disease is still present in urban elms. While it appears that S. schevyrewi is another vector of the DED pathogens, it appears that S. schevyrewi is no more efficient than S. multistriatus. Thus, management programs that remove elm bark beetle breeding sites, rapidly remove DED-infected elms and include the planting of DED-resistant elms should continue to be effective management tactics. [ABSTRACT FROM AUTHOR]

Copyright of Silva Lusitana is the property of Unidade de Investigacao de Silvicultura e Productos Florestais and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We studied the biology of Scolytus subscaber LeConte (Coleoptera: Curculionidae: Scolytinae) in grand fir, Abies grandis (Douglas) Lindley, in northern Idaho. Presented are new Idaho distribution records, description of the mature larva and adult, biological features, characteristics of infestation and galleries, and natural control factors. The beetle has one generation per year, taking flight in July to infest live branches in the crowns of mature trees. The uniquely shaped egg gallery deeply scores the wood; its two arms curve inward like the Greek letter e. Eggs are laid along the outer edge of the gallery; hatched larvae mine hidden in the phloem for a short distance after which they mine next to the sapwood where they overwinter. A cerambycid, Tetropium abietis Fall, occurred often in the larger diameter portion of branches infested with S. subscaber. A scolytid, Scolytus abietis Blackman, also infested branches but not those containing S. subscaber. Mortality factors included a braconid parasitoid, Ecphylus arcuatus Muesebeck, on larvae and the flooding of egg galleries with resin evidently caused by defensive response of the host tree to a staining fungus, Spicaria anomala (Corda) Harz., carried by the beetle. In addition, we point out errors and lack of documentation concerning the identity, biology, and behavior of S. subscaber in secondary published sources. [ABSTRACT FROM AUTHOR]

A new species of bark-beetle from Kashmir, Scolytus stepheni sp. n., dedicated to the late Professor Emeritus Stephen Lane Wood, is described and figured. Key to Indian Scolytus Geoffroy, 1762 species is provided. [ABSTRACT FROM AUTHOR]

Five new species of Scolytus Geoffroy, 1762 (Coleoptera: Curculionidae: Scolytinae) are described from Peru, namely S. woodi, S. carveli, S. vagabundus, S. lindemani, S. mozolevskae. Th e following new synonym is established: Scolytus angustatus Browne, 1970 (= Scolytus facialis Schedl, 1973, syn. n.) New records of the Scolytus species in Loreto, Junin ,Cusco and Madre de Dios Provinces are given and the biology of the genus representatives is discussed. [ABSTRACT FROM AUTHOR]

The identification of Scolytus fagi Walsh has been difficult because of the lack of diagnostic literature, the occurrence of several morphologically similar sympatric Scolytus species and the loss of the syntypes. In an effort to reduce taxonomic confusion, we designate a neotype for S. fagi, redescribe the male and female, add new distributional records and create a key for the identification of eastern Scolytus species. [ABSTRACT FROM AUTHOR]

Anatomical features of male and female Scolytus opacus Blackman, infesting Abies lasiocarpa (Hook.), and Scolytus abietis Blackman (Coleoptera: Curculionidae: Scolytinae), infesting Abies grandis (Douglas) and Abies concolor (Gord. & Glend.), were compared by light and scanning electron microscopy. Diagnostic features involve body size; striations on the underside of the head, which have a stridulatory function; shape of the submentum; and several characters on abdominal sternites 1 and 2. Because of differences in these features of the two taxa, and because the two populations infest different tree species and are sympatric in Idaho, we reinstate S. abietis as a valid species. [ABSTRACT FROM AUTHOR]

Abstract: Several elm-infesting bark beetles belonging to the genus Scolytus (Coleoptera: Scolytinae) are vectors of Ophiostoma spp., most notably the Dutch elm disease fungi. A related bark beetle species, Scolytus ratzeburgi, is known to infest birch in various parts of Europe, but it is unknown whether fungi are associated with this beetle. The aim of this study was to identify several fungal species isolated from S. ratzeburgi. Beetles and their galleries were collected from Betula pendula at three different sites in the boreal forests of the Karelia region, on both the Finnish and Russian sides of the border. Three ophiostomatoid fungi were isolated from the beetles and their galleries. One Penicillium and one Bionectria species were isolated only from the Finnish material and, based on DNA sequences, were identified as P. brevicompactum and a species close to the anamorph of B. zelandianovae. Two Ophiostoma species present in low numbers included O. quercus and a species closely related to O. catonianum. Only one Ophiostoma species was isolated consistently from all the galleries and beetles considered in the study. Comparison of DNA sequences and morphological characterization showed that this fungus represents an undescribed taxon, described here as O. karelicum sp. nov. [Copyright &y& Elsevier]

Abstract: Insects are major components of forest ecosystems, representing most of the biological diversity and affecting virtually all processes and uses. In the USA, bark beetles (Coleoptera: Curculionidae, Scolytinae) heavily influence the structure and function of these ecosystems by regulating certain aspects of primary production, nutrient cycling, ecological succession and the size, distribution and abundance of forest trees. The purpose of this report is to review tree and stand factors associated with bark beetle infestations and analyze the effectiveness of vegetation management practices for mitigating the negative impacts of bark beetles on forest ecosystems. We describe the current state of our knowledge and identify gaps for making informed decisions on proposed silvicultural treatments. This review draws from examination of 498 scientific publications (many of which are cited herein) on this and related topics. [Copyright &y& Elsevier]

Abstract: Over the last century, fire exclusion in the forests of the Sierra Nevada has allowed surface fuels to accumulate and has led to increased tree density. Stand composition has also been altered as shade tolerant tree species crowd out shade intolerant species. To restore forest structure and reduce the risk of large, intense fires, managers have increasingly used prescription burning. Most fires prior to EuroAmerican settlement occurred during the late summer and early fall and most prescribed burning has taken place during the latter part of this period. Poor air quality and lack of suitable burn windows during the fall, however, have resulted in a need to conduct more prescription burning earlier in the season. Previous reports have suggested that burning during the time when trees are actively growing may increase mortality rates due to fine root damage and/or bark beetle activity. This study examines the effects of fire on tree mortality and bark beetle attacks under prescription burning during early and late season. Replicated early season burn, late season burn and unburned control plots were established in an old-growth mixed conifer forest in the Sierra Nevada that had not experienced a fire in over 120 years. Although prescribed burns resulted in significant mortality of particularly the smallest tree size classes, no difference between early and late season burns was detected. Direct mortality due to fire was associated with fire intensity. Secondary mortality due to bark beetles was not significantly correlated with fire intensity. The probability of bark beetle attack on pines did not differ between early and late season burns, while the probability of bark beetle attack on firs was greater following early season burns. Overall tree mortality appeared to be primarily the result of fire intensity rather than tree phenology at the time of the burns. Early season burns are generally conducted under higher fuel moisture conditions, leading to less fuel consumption and potentially less injury to trees. This reduction in fire severity may compensate for relatively modest increases in bark beetle attack probabilities on some tree species, ultimately resulting in a forest structure that differs little between early and late season prescribed burning treatments. [Copyright &y& Elsevier]

IN FEBRUARY 2005, THE EXOTIC BARK BEETLE, Scolytus kirschii (Curculionidae: Scolytinae), was detected infesting English elms (Ulmus procera) in Stellenbosch, South Africa. This appears to be the first report of an infestation of Scolytus species in this country. The presence of this beetle is of concern for several reasons. Scolytus kirschii is a serious pest of elms, capable of killing healthy frees, resulting in considerable economic impact. There also exists the possibility that the beetle may undergo a host switch to indigenous frees, with potentially serious ecological consequences. Furthermore, the beetle is capable of being the vector of the pathogens responsible for Dutch elm disease (DED), Ophiostoma ulmi and Ophiostoma novo-ulmi. None of the frees that we inspected in Stellenbosch exhibited symptoms or signs of DED. Isolations from infested host material likewise failed to detect these pathogens. Nonetheless, the damage to the frees by the beetles alone was sufficient to cause free death. Future directions for research and management of the beetle in its new environment are discussed. [ABSTRACT FROM AUTHOR]

To understand the role of chemical signals involved inScolytus intricatus(Ratzeburg) (Col., Scolytidae) host colonization, the attractiveness of intact and beetle colonized host material was investigated in the field and in the laboratory. In the field, chemical signals operating at long range were investigated by means of sticky traps. In the laboratory, close-range chemical interactions were investigated with an arena olfactometer. Field experiments showed no differences in the attractiveness between infested and non-infested host material. On the contrary, laboratory experiments revealed higher attractiveness of infested host and beetle-produced frass in comparison with intact host and mechanically produced sawdust respectively. Laboratory data also disclosed the attractiveness of beetle extracts of both sexes. Our data show that: (1) host kairomones play an important role during host colonization, and that (2)S. intricatusdoes not use a sex-specific secondary attractant system. Differences between results of field and laboratory trials are discussed. [ABSTRACT FROM AUTHOR]

Abstract: As the vector of vascular fungi of the genus Ophiostoma the oak bark beetle, Scolytus intricatus, is one of the significant links in the chain of agents of oak forest decline in Serbia. It is known that the adults of this bark beetle, which develop under the bark of the trees infected by fungi of the genus Ophiostoma, transport the spores of these fungi. During the maturation feeding, the spores are transmitted to healthy tree crowns, where they germinate and cause infection. In period 1992–96 at 27 localities in Serbia, the significance of parasitoids in the reduction of this bark beetle was examined, as the intensity of spore transmission depends upon the number of oak bark beetle adults in nature. In the research of parasitoids of S. intricatus 20 species were identified in five families of Hymenoptera: Braconidae (six species), Eurytomidae (one), Pteromalidae (10), Eupelmidae (one) and Eulophidae (two). Among these parasitoids the greatest influence on the abundance of oak bark beetle was the species Ecphylus silesiacus. It was identified in 90.91% of study samples, its domination was 39.15% and the percentage of oak bark beetle parasitism was 5.66%. In addition, the species Entendon ergias, Dendrosoter protuberans and Cheiropachus quadrum were significant in reduction of S. intricatus. The average percentage of parasitism of oak bark beetle by E. ergias was 2.74%, by D. protuberans it was 2.63% and by Ch. quadrum 1.63%. The significance of other parasitoids in the reduction of oak bark beetles was low. In the study period the total parasitism of oak bark beetle varied between a minimum of 8.64% in 1992 and a maximum of 19.64% in 1996. The average for the whole study period was 14.49%. [ABSTRACT FROM AUTHOR]

Two bioactive compounds, viz. 4-methylheptan-3-ol (I) and 4-methylheptan-3-one (II) have been identified in European oak bark beetle (Scolytus intricatus) extracts by gas chromatography coupled with mass spectrometric and electroantennographic detector systems. Further examination of these compounds using gas chromatography on chiral stationary phases, as well as a comparison with optically active standards proved the absolute configuration of the identified compounds to be (3R,4S)-I and (S)-II. The discovery of (3R,4S)-I and (S)-II as insect-produced compounds in both sexes of S. intricatus constitutes the first reported occurrence in this species. [Copyright &y& Elsevier]

Studies the attraction of Scolytus unispinosus (S. unispinosus) bark beetles to ethanol in water-stressed branches of Douglas fir. Concentration of ethanol in needles and woody tissues from stressed branches of Douglas fir, sampled after being attacked by S. unispinosus; Percentage of their total monoterpenes lost by drying needles from water-stressed branches of Douglas fir; Possible reason for initiation of ethanol synthesis in stressed branches of Douglas fir.

In the forest of Kljestevica, the elm is attacked by four species of elm bark beetles: Scolytus multistriatus (Marsh.), Scolytus scolytus (Fab.), Scolytus pygmaeus (Fab.) and Scolytus ensifer (Rich.) (Col., Scolytidae). Scolytus multistriatus and S. pygmaeus are the most numerous species. Elm bark beetle is parasitized by four species of parasites: Dendrosoter protuberans (Nees), Ecphylus silesiacus (Ratz.), Coeloides scolyticida (Wesm.) (Hym., Braconidae) and Entedon leucogramma (Ratz.) (Hym., Eulophidae). Ecphylus silesiacus and D. protuberans are the most numerous species. The nectar of mustard (Sinapis alba L., Brassicaceae) flowers, sweet basil (Stachys recta L., Lamiaceae) flowers and of wild carrot (Daucus carota L., Umbelliferae), has an important effect on the number of parasites and on the parasitism of the elm bark beetles. Wild carrot is the most attractive plant to the parasites for additional nutrition, especially for D. protuberans. Mustard and sweet basil flowers are suitable for additional nutrition of E. silesiacus imagos. On meadow flowers growing spontaneously in forest clearings, the lowest number of parasite imagos was collected by an entomological catcher, and the lowest percentage of parasitized larvae and eggs of the elm bark beetle was recorded in elm control catch trunks that were not near the cultivated melliferous plants. [ABSTRACT FROM AUTHOR]

first documented report for Scolytus schevyrewi Semenov (Curculionidae: Scolytinae), an exotic species of Mexico. [ABSTRACT FROM AUTHOR]

In laboratory experiments elm bark beetles (Scolytus scolytus and S. multistriatus) were allowed to choose between English elm and one of six other taxa (Smooth-leaved, Wheatley, Wych, Huntingdon, Commelin 274 and Cornish) for maturation feeding. Preference was sometimes shown for English elm over Huntingdon and Commelin elms and, on one occasion, Wheatley elm was fed on more than English. However, there was no consistent pattern. Sufficient feeding occurred on all taxa to enable spores of the Dutch, elm disease fungus (Ceratocystis ulmi) to be introduced to the twigs. [ABSTRACT FROM AUTHOR]

Sections of two pollarded parkelms ( Ulmus glabra) from Damsgaard, Bergen, west Norway have been studied. Changes in annual ring-width are attributed partly to management, namely pollarding, and partly to pathogenic attacks, probably by Ceratocystis ulmi. The oldest attack on the trees dates back to 1826: so far the oldest known record of Dutch elm disease in Norway. Pollarding may be an important factor in attacks by the pathogen within parkelms. A possible relationship between pollarding, the pathogen and the Neolithic elmfall is suggested. [ABSTRACT FROM AUTHOR]

The smaller European elm bark beetle, Scolytus multistriatus, has been the primary vector of the Dutch elm disease fungus, Ophiostoma novo-ulmi, in elm trees in Colorado since 1948. An exotic from Asia, the banded elm bark beetle, Scolytus schevyrewi, was found in Siberian elm, Ulmus pumila, in Colorado in April of 2003; this was the first report of S. schevyrewi in North America. S. schevyrewi is now found throughout much of Colorado and in at least 21 other states. The similarities in breeding and feeding habits between S. schevyrewi and S. multistriatus have raised concerns about the ability of S. schevyrewi to serve as a vector for O. novo-ulmi. The objective of this preliminary study was to determine if O. novo-ulmi could be isolated from adult S. schevyrewi emerging from diseased elm trees. S. schevyrewi and S. multistriatus were allowed to infest diseased stem segments of American elm, Ulmus americana. The infested stem segments were caged and isolations were made from the adult brood that emerged. O. novo-ulmi was isolated from most of the adults of both beetle species, showing that S. schevyrewi could acquire the pathogen as effectively as S. multistriatus. Future studies are needed to determine if S. schevyrewi can effectively transmit the pathogen to healthy trees. [ABSTRACT FROM AUTHOR]

The article offers information on the plant pest Scolytus morawitzi Semenow which is commonly known as Morawitz's bark beetle. Mass flight of this pest usually occurs from mid-July to the end of August. The leaves of trees attacked by S. morawitzi often show yellowing and wilting. This species prefers to attack mature trees. Natural spread of the pest is not very rapid.

Fifteen elm trees ranging in DBII from 25 to 40 cm were inoculated with ca. 8 mm diameter pellets containing propagates of Trichoderma viride IMI 206039 and IMI 206040 besides nutrients. These pellets were inserted in the trunks every 10cm around the circumference. Dead elms present upwind and downwind from the 15 treated elms remained standing during the four year duration of the experiment. No progress in the disease occurred during three growing seasons after the original treatment. During the fourth growing season (1982) 4 elms died and 11 survived, though one was severely damaged. These 11 surviving trees were retreated in September 1982. [ABSTRACT FROM AUTHOR]

In 1971 and 1972 populations of Scolytus scolytus (F.) in several counties in England were heavily parasitized by Parasitaphelenchus oldhami Rühm, but in S. multistriatus (Marsh.) P. oldhami was markedly less abundant. Infestation of S. scolytus was 54 per cent in 1971 and 61 per cent in 1972, while the mean number of parasites per infested beetle was 32 and 41 respectively. For S. multistriatus the comparable figures were 55 per cent in 1971 and 44 per cent in 1972 with means of 12 and 10 parasites per beetle. Despite the high levels of parasitism, no pathological effects on the beetles were observed. [ABSTRACT FROM AUTHOR]