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Pest density--plant damage relationships are essential guides for decision-making in integrated pest management. In this article, we established pest density--leaf damage relationships for the beech leaf-mining weevil, Orchestes fagi L. (formerly Rhynchaenus fagi, Coleoptera: Curculionidae), in its invasive range of Nova Scotia, Canada. Outbreaks of O. fagi cause tree-wide leaf necrosis in American beech (Fagus grandifolia Ehrh.), which can eventually result in tree mortality. In 2014 and 2016, we collected weekly samples in stands with American beech and assessed leaves for densities during different life stages (eggs, larvae, and pupae), population proxy measures (adult feeding damage, egg slits, and larval galleries), and percent necrosis. In general, feeding damage and leaf necrosis plateaued soon after the end of budburst, but before the larval mine expanded. This strongly suggested that leaf necrosis may be linked to damage caused by adults or by mine initiation rather than that caused by larval mine expansion and gallery development. The density of O. fagi per leaf for life stages and population proxies all significantly explained ~42%-81% of the variation in end-of-season percent leaf necrosis. Results from this study provide a variety of relationships that could be used in both short- and long-term monitoring efforts for O. fagi. Key words: beech leaf-mining weevil, density-damage relationships, invasive species, integrated pest management. Les relations entre la densite des ravageurs et les dommages qu'ils causent chez les vegetaux constituent des guides essentiels pour la prise de decision dans la lutte integree contre les ravageurs. Dans cet article, nous avons etabli des relations entre la densite d'un ravageur et les dommages foliaires dans le cas de l'orcheste du hetre, Orchestes fagi L. (anciennement Rhynchaenus fagi, coleoptere, Curculionidae) dans les aires envahies de la Nouvelle-Ecosse, au Canada. Les epidemies de O. fagi causent la necrose des feuilles partout dans l'arbre chez le hetre d'Amerique (Fagus grandifolia Ehrh.) qui peut eventuellement entrainer la mort des arbres. En 2014 et 2016, nous avons effectue des prelevements hebdomadaires d'echantillons dans des peuplements ou le hetre d'Amerique etait present et nous avons evalue les feuilles pour la densite durant les differents stades de vie (oeufs, larves, pupes), pris des mesures indirectes de la population (dommages dus au prelevement alimentaire des adultes, encoches de ponte et galeries larvaires) et determiner le pourcentage de necrose. En general, les dommages dus au prelevement alimentaire et la necrose foliaire ont atteint un plateau peu de temps apres la fin du debourrement mais avant l'expansion des galeries larvaires. Cela suggere fortement que la necrose des feuilles pourrait etre liee aux dommages causes par les adultes ou l'initiation de l'activite des larves plutot qu'a ceux causes par l'expansion de l'activite des larves et le developpement des galeries. La densite de O. fagi par feuille durant les differents stades de vie et les mesures indirectes de population expliquaient environ 42-81% de la variation dans le pourcentage de necrose foliaire en fin de saison. Les resultats de cette etude fournissent une variete de relations qui pourraient etre utilisees en appuie aux efforts de suivi a court et long termes de O. fagi. [Traduit par la Redaction] Mots-cles : orcheste du hetre, relations entre la densite d'un ravageur et la severite des dommages, especes invasives, lutte integree contre les ravageurs., 1. Introduction Efficient use of control tactics in integrated pest management (IPM) requires an understanding of relationships between herbivore density and associated host plant damage. More specifically, pest density--damage relationships [...]

Mountain pine beetle (Dendroctonusponderosae Hopkins; Coleoptera: Curculionidae, Scolytinae) has killed millions of hectares of lodgepole pine (Pinus contorta Douglas ex Loudon) forest in western Canada, where it has recently established in the novel host jack pine (Pinus banksiana Lamb.) and threatens naive red pine (Pinus resinosa Aiton) forests as the current outbreak expands eastward. It is therefore crucial to understand whether red pine is a suitable host for D. ponderosae. Host suitability was assessed by comparing the ability of beetles to produce pheromones and complete their development in red pine bolts inoculated with mating beetle pairs. We detected two of four primary pheromones, including trans-verbenol and verbenone, but not exo-brevicomin or frontalin. Beetle brood successfully developed in bolts, with reproductive parameters (e.g., female and larval galleries, pupal chamber, and number of broods emerged per mated pair of adults) that were similar to those reported from the beetle's historical host lodgepole pine and the novel host jack pine. These results provide initial evidence that red pine is a suitable host for D. ponderosae. However, it is unclear how either low concentrations or an absence of exo-brevicomin, frontalin, and the synergistic monoterpene myrcene could affect host colonization and establishment of beetles. Key words: invasion biology, range expansion, boreal forest, bark beetle, pheromones. Le dendroctone du pin ponderosa (Dendroctonusponderosae Hopkins; Coleopteres: Curculionidae, Scolytinae) a tue des millions d'hectares de foret de pin tordu (Pinus contorta Douglas ex Loudon) dans l'ouest du Canada ou il s'est recemment etabli sur un nouvel hote, le pin gris (P. banksiana Lamb.) et menace les forets de pin rouge (Pinus resinosa Aiton) a mesure que l'epidemie s'etend vers l'est. Il est par consequent crucial de determiner si le pin rouge est un hote approprie pour le dendroctone. Nous avons evalue dans quelle mesure le pin rouge est un hote approprie en comparant la capacite du dendroctone a produire des pheromones et a completer son developpement dans des billots de pin rouge inocules avec des couples de dendroctone. Nous avons detecte deux des quatre pheromones primaires, incluant le trans-verbenol et la verbenone mais pas l'exo- brevicomine ni la frontaline. La progeniture du dendroctone a reussi a se developper dans les billots et les parametres de la reproduction (p. ex., galeries creusees par les femelles et les larves, loge nymphale et nombre de generations qui ont emerge par couple d'adultes) etaient similaires a ceux qui ont ete rapportes sur l'hote traditionnel du dendroctone, le pin tordu, et son nouvel hote, le pin gris. Ces resultats fournissent un premier indice que le pin rouge est un hote adequat pour D. ponderosae. Cependant, il n'est pas clair dans quelle mesure de faibles concentrations ou l'absence d'exo-brevicomine, de frontaline et de myrene, un monoterpene synergique, pourraient etre nefastes pour la colonisation de l'hote ou l'etablissement du dendroctone. [Traduit par la Redaction] Mots-cles: biologie de l'invasion, expansion de l'aire de repartition, foret boreale, scolyte, pheromones., Introduction The mountain pine beetle (Dendroctonus ponderosae Hopkins; Coleoptera: Curculionidae, Scolytinae) has killed several million hectares of conifer forests, primarily lodgepole pine (Pinus contorta Douglas ex Loudon), in western Canada [...]

The Coleoptera fauna of the province of Prince Edward Island has long been one of the most poorly known jurisdictions in Canada, with fewer than half the number of species recorded in the neighbouring provinces of New Brunswick and Nova Scotia. If much of the difference in species richness was due to less intensive sampling of the province compared to other parts of Atlantic Canada it was predicted that surveys with semiochemical-baited traps would detect many previously undetected species. Lindgren funnel traps were baited with longhorn beetle pheromones and host volatiles and placed in the canopy and understory of coniferous and deciduous trees at the Valleyfield, New Harmony, Auburn, and Brookvale Demonstration Woodlots during the summers of 2018 and 2019. Two hundred and ninety-five species of Coleoptera are newly recorded from Prince Edward Island from 53 families. One of these, the Palaearctic Pityophagus ferrugineus (Linnaeus, 1760) is reported for the first time from North America and Canada. The families Lycidae, Derodontidae, Lymexylidae, Sphindidae, Cucujidae, Ripiphoridae, Salpingidae, and Nemonychidae are newly recorded for the province. A checklist of the Coleoptera of Prince Edward Island is provided. [ABSTRACT FROM AUTHOR]

The Middle Jurassic Todilto Member of the Wanakah Formation is a carbonate and gypsum unit inset into the underlying aeolian Entrada Sandstone in the San Juan Basin. Field and thin section study of the uppermost Entrada and Todilto at Ghost Ranch, New Mexico, identified Todilto facies and their relationship to remnant Entrada dune topography. Results support the previous interpretation that the Entrada dunes, housed in a basin below sea level, were rapidly flooded by marine waters. Mass wasting of the dunes gave rise to sediment‐gravity flows that largely buried remnant dune topography, leaving ca 12 m of relief that defined the antecedent condition for Todilto deposition. Previously interpreted as seasonal varves deposited in a stratified water body, the Todilto is reinterpreted as a microbial biolaminite. Most diagnostic are organic‐rich laminae with structures characteristic of filamentous microbes and containing trapped aeolian silt, and clotted‐texture laminae with a fabric associated with calcification of extracellular polymeric substances. The spatial arrangement of Todilto facies is controlled by the dune palaeotopography. A continuous basal laminated mudstone thickens over the dune crest, reflecting the optimum conditions for microbial mat development, and is interpreted to have been deposited when marine waters submerged the topography. Subsequent drying caused emergence of the crestal area, and formation of tepee structures and a dissolution breccia. Gypsiferous mudflats and periodic ponds occupied the dune flanks and interdune area, with gypsum concentrated within the interdune area. Entrada sands remained unstable during Todilto deposition with common injection structures into the Todilto, and a remnant slope caused the downslope movement and folding of Todilto strata on the upper lee face. Although some expansion of the gypsum occurred in the subsurface, facies architecture fostered development of a dissolution front adjacent to the interdune gypsum body with section collapse of gypsiferous limestone on the dune flanks. [ABSTRACT FROM AUTHOR]

We investigated the potential for human-mediated range expansion of an exotic beech leaf-mining weevil, Orchestes fagi (Linnaeus) (Coleoptera: Curculionidae: Curculioninae: Rhamphini) (formerly known as Rhynchaenus fagi) on timber or firewood, which for eight to nine months of the year may harbour adults in diapause. In both relatively low-density and high-density populations, adults were found on the base, middle, and upper boles of the primary host, American beech (Fagus grandifolia Ehrhart; Fagaceae), as well as red maple (Acer rubrum Linnaeus; Sapindaceae) and red spruce (Picea rubens Sargent; Pinaceae) in the vicinity. Comparatively few individuals were found on tree branches, or in the moss, duff, or soil collected beneath beech trees. Overwintering adults appeared to favour parts of trees with relatively high bark roughness. Our study suggests that, between the months of July through May, any woody stems near areas having O. fagi outbreaks are likely to harbour adults. Moreover, as all of the trees studied are common sources of timber or firewood, the harvest and transport of wood from these areas may facilitate outbreak spread; this may explain the multiple, distantly distributed populations of O. fagi that have been reported in eastern Nova Scotia, Canada in recent years. [ABSTRACT FROM PUBLISHER]

The Ciidae of New Brunswick, Canada are reviewed. Seventeen species are recorded for New Brunswick, including the following 10 species that are newly recorded for the province: Ceracis singularis (Dury), Ceracis thoracicornis (Ziegler), Cis angustus Hatch, Cis fuscipes Mellié, Cis horridulus Casey, Cis striatulus Mellié, Dolichocis laricinus (Mellié), Malacocis brevicollis (Casey), Orthocis punctatus (Mellié), and Plesiocis cribrum Casey. Additional locality data are provided for the following species previously known from the province: Cis americanus Mannerheim, Cis creberrimus Mellié, Cis levettei (Casey), Cis submicans Abeille de Perrin, Dolichocis manitoba Dury, Hadreule elongatula (Gyllenhal), and Octotemnus glabriculus (Gyllenhal). Seven synonyms are proposed here; Cis pistoria Casey with C. submicans Abeille de Perrin; C. fraternus Casey, C. macilentus Casey and C. striolatus Casey with C. striatulus Mellié; Dolichocis indistinctus Hatch with D. laricinus (Mellié); and Octotemnus denudatus Casey and O. laevis Casey with O. glabriculus (Gyllenhal). Lindgren funnel traps provided the majority of specimens for 15 of the 17 species reported from New Brunswick and were the sole source of specimens for seven of the 10 species newly reported here, suggesting they are a very useful tool for sampling Ciidae in the forests of New Brunswick. [ABSTRACT FROM AUTHOR]

The upper tree crown represents an important habitat for many insect herbivores but, being much less commonly sampled than the understory, remains poorly understood. Here, we provide detailed instructions and quantitative cost (time) estimates for setting up insect traps in the upper crown of trees using methods adapted from tree-climbing canopy ecologists. In a sample experiment, we recorded the time it took for a two-person crew ("shooter" and assistant) to install traps in the upper crown vs. the understory of a mature stand of eastern hemlock (Tsuga canadensis (L.) Carrière (Pinaceae)), with trees 18-24 m tall. A crew with 3 yrs experience with these methods took an average of 5 min 38 s (range 3 min 13 s to 17 min 39 s) to install a trap in the upper crown, whereas an inexperienced field technician took an average of 7 min 1 s per tree (range 5 min 47 s to 9 min 19 s). In comparison, it required on average only 1 min 19 s (experienced) and 1 min 48 s (inexperienced) to install a trap in the understory. We used an average of 50 m (range 31-61 m) of rope per crown trap compared with 4.5 m (range 3.5-5.5 m) per understory traps, which translated to a difference in cost of CDN$2.50 per trap, based on 2013 prices. Our results demonstrate that it costs more in time and materials to place traps in the upper crown vs. the understory, but the additional costs are modest. Furthermore, we show that an inexperienced person can learn how to set high traps quickly by following the step-by-step instructions laid out in this paper. We hope this both encourages and enables more use of traps in the upper crown as well as the understory when surveying for species of bark- and wood-boring beetles and other forest insects. [ABSTRACT FROM AUTHOR]