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Count Carl Gustaf Mannerheim, a Finnish entomologist and government administrator, made significant contributions to the understanding of beetles in Pacific Northwestern America. Despite never visiting North America himself, Mannerheim enlisted the help of Finnish settlers in Russian America to collect insects for him, resulting in a valuable collection that supported his research for 15 years. Mannerheim's four monographic publications on the beetle fauna of the region were considered comprehensive and authoritative at the time, and he is recognized as a founder of coleopterology in western North America. His work was highly collaborative and followed progressive systematic approaches. The Finnish Museum of Natural History houses the Coleoptera Mannerheim collection, which contains about 20,000 species and 100,000 specimens, including 800 type specimens described by Mannerheim himself. [Extracted from the article]

: A complex of nine invasive weevils has established in the northern hardwood forests of the Great Lakes Region. These weevils have become the numerically dominant arthropod fauna in the lower vegetation strata of this ecosystem. Effects of these folivorous adults and rhizophagous larvae on seedling survival and density are unknown. We measured the impact of adult weevil defoliation on individual sugar maple (Acer saccharum Marshall) seedlings, the numerically dominant flora in these stands. Over 14 500 seedlings were measured to examine the effects of larval abundance, adult abundance, and adult defoliation on seedling dynamics during 2005-2009. Heavy defoliation led to individual sugar maple seedling mortality. However, at the stand level there was no measureable net effect of invasive weevils against the high natural background rates of seedling mortality. Seedling growth and biomass were reduced by high adult or larval populations, which were associated with heavy leaf and root herbivory, but not by moderate adult or larval populations. We conclude that high levels of redundancy and compensatory processes in this environment allow sugar maple seedling populations to tolerate high levels of weevil damage, although additional stresses could reduce this resilience. Resume: Un complexe de neuf charancons invasifs s'est etabli dans les forets de feuillus nordiques de la region des Grands lacs. D'un point de vue numerique, ces charancons sont devenus la faune dominante d'arthropodes dans les strates inferieures de vegetation de cet ecosysteme. Les effets de ces adultes folivores et de ces larves rhizophages sur la survie et la densite des semis sont inconnus. Nous avons mesure l'impact de la defoliation causee par les charancons adultes sur des semis individuels d'erable a sucre (Acer saccharum Marshall), la flore numeriquement dominante dans ces peuplements. Plus de 14 500 semis ont ete mesures pour etudier les effets de l'abondance des larves, de l'abondance des adultes et de la defoliation causee par les adultes sur la dynamique des semis durant la periode 2005-2009. Une defoliation severe a entraine la mort de certains semis d'erable a sucre. Cependant, a l'echelle du peuplement il n'y avait pas d'effet net mesurable des charancons invasifs considerant le taux naturellement eleve de mortalite des semis. La croissance et la biomasse des semis etaient reduites par de fortes populations d'adultes ou de larves associees au broutage severe des feuilles et des racines, mais ce n'etait pas le cas lorsque les populations d'adultes ou de larves etaient moderees. Nous concluons que la presence de nombreux processus redondants et compensatoires dans cet environnement permet aux populations de semis d'erable a sucre de tolerer des dommages importants causes par les charancons mais des stress additionnels pourraient reduire cette resilience. [Traduit par la Redaction], Introduction Exotic insect herbivores can cause substantial environmental and economic harm to native ecosystems (Bohlen et al. 2004), but our ability to assess and mitigate impacts is limited, especially with [...]

Abstract: We summarize the effects of major weather events such as ice storms, wind storms, and flooding on the abundance and diversity of terrestrial forest insects and their allies. This [...]

Elevated levels of CO2 affect plant growth and leaf chemistry, which in turn can alter host plant suitability for insect herbivores. We examined the suitability of foliage from trees grown from seedlings since 1997 at Aspen FACE as diet for the gypsy moth (Lymantria dispar L.) Lepidoptera: Lymantriidae: paper birch (Betula papyrifera Marshall) in 2004-2005, and trembling aspen (Populus tremuloides Miehaux) in 2006-2007, and measured consequent effects on larval respiration. Leaves were collected for diet and leaf chemistry (nutritional and secondary compound proxies) from trees grown under ambient (average 380 ppm) and elevated CO2 (average 560 ppm) conditions. Elevated CO2 did not significantly alter birch or aspen leaf chemistry compared with ambient levels with the exception that birch percent carbon in 2004 and aspen moisture content in 2006 were significantly lowered. Respiration rates were significantly higher (15-59%) for larvae reared on birch grown under elevated CO2 compared with ambient conditions, but were not different on two aspen clones, until larvae reached the fifth instar, when those consuming elevated CO2 leaves on clone 271 had lower (26%) respiration rates, and those consuming elevated CO2 leaves on clone 216 had higher (36%) respiration rates. However, elevated CO2 had no apparent effect on the respiration rates of pupae derived from larvae fed either birch or aspen leaves. Higher respiration rates for larvae fed diets grown under ambient or elevated CO2 demonstrates their lower efficiency of converting chemical energy of digested food stuffs extracted from such leaves into their biosynthetic processes. [ABSTRACT FROM AUTHOR]

An obituary for William E. Miller, professor of entomology at the University of Minnesota, is presented.

We studied the three-way interaction of elevated CO2, nitrogen (N), and temperature ( T), and the two-way interaction of elevated CO2 and early-season defoliation on the secondary chemistry and resistance of Eurasian silver birch ( Betula pendula) and North American paper birch ( B. papyrifera) against the Eurasian hare ( Lepus timidus) and the North American eastern cottontail rabbit ( Sylvilagus floridanus), respectively. Elevated CO2 decreased the palatability of winter-dormant silver and paper birch stems to both hares and rabbits, respectively. But the effect on hares was only apparent at intermediate levels of N fertilization. Elevated T had no effect on palatability. The effects of elevated CO2, N, and T on levels of silver birch bark phenolics and terpenoids were dominated by two-way interactions between N and CO2, and N and T. Generally, however, N amendments elicited a parabolic response in carbon partitioning to most biosynthetic classes of silver birch phenolics (i.e. highest concentrations occurring at intermediate N). CO2 elevation was most enhancing at highest levels of N. On the other hand, T increases, more often than not, elicited reductions in phenolics, but especially so at the highest N level. In the case of B. papyrifera, elevated CO2 increased carbon partitioning to Folin-Denis stem and branch phenolics and condensed tannins. Early-season defoliation, on the other hand, had no effect on phenolics and tannins but lowered both N and energy levels of branches. Elevated CO2 substantially ameliorated the negative effects of severe defoliation on tree growth. These results support the hypothesis that continuing anthropogenic alterations of the atmosphere may trigger significant changes in plant phenotypic resistance to mammalian herbivores owing to an increasing net carbon balance between the highly vagile supply and demand capacities of plant carbon sources and sinks. [ABSTRACT FROM AUTHOR]