by Dr. Molly Darr | May 24, 2022 | 2021-Present Publications, Southern Pine Beetle
Abstract
Seven new Entomocorticium species (Peniophoraceae) are described based on morphology and phylogenetic analyses. Along with the type species (E. dendroctoni), Entomocorticium comprises eight species of nutritional symbionts of pine bark beetles in North America. Entomocorticium cobbii is the mycangial associate of the southern pine beetle, Dendroctonus frontalis, and E. parmeteri is the mycangial associate of the western pine beetle, D. brevicomis. Entomocorticium whitneyi, E. portiae, E. kirisitsii, E. oberwinkleri and the previously described E. dendroctoni have been isolated from galleries of D. ponderosae and D. jeffreyi in western North America. Entomocorticium sullivanii forms an ambrosia-like layer of basidia and basidiospores in the pupal chambers of Ips avulsus in the southeastern USA. Entomocorticium is phylogenetically placed within Peniophora, a corticioid genus of wood decay fungi with wind-dispersed basidiospores. At least four species of Entomocorticium produce basidiospores on basidia with reduced sterigmata that apparently do not forcibly discharge basidiospores. Another basidiomycete, Gloeocystidium ipidophilum, was described from Ips typographus galleries in Europe, but it is phylogenetically and taxonomically placed in another genus of wood decay fungi as Cylindrobasidium ipidophilum (Physalacriaceae). The free-living wood-decay fungus Phlebiopsis gigantea (Phanerochaetaceae) has been occasionally associated with bark beetles but is unrelated to C. ipidophilum or Entomocorticium.
Keywords
Insect symbionts, Mutualism, Agaricomycetes
To read the full article please visit the link below:
Harrington, T. C., J. C. Batzer, and D. L. McNew. 2021. “Corticioid Basidiomycetes Associated with Bark Beetles, Including Seven New Entomocorticium Species from North America and Cylindrobasidium Ipidophilum, Comb. Nov.” Antonie Van Leeuwenhoek International Journal of General and Molecular Microbiology 114 (5): 561–79. https://doi.org/10.1007/s10482-021-01541-7.
by Dr. Molly Darr | May 24, 2022 | 2011-2020 Publications, Southern Pine Beetle
Abstract
The use of woody biomass as a feedstock for wood-burning energy facilities and pellet mills has increased across the southern United States in recent years. Feedstock for these facilities comes in a variety of forms, including roundwood, logging residues, and mill residues. Precommercial thinning (PCT) of pine stands is sometimes used to mitigate southern pine beetle (Dendroctonus frontalis) risk that traditionally incurs added cost to landowners. Utilization of biomass from PCT for biomass energy production may provide an opportunity to reduce the costs of southern pine beetle risk mitigation practices. Potential use of PCT biomass has been suggested in previous studies, but little effort has focused on quantifying amounts available for utilization. Using a list of nonindustrial, private forests enrolled in the Virginia Department of Forestry Pine Bark Beetle Prevention Program, we conducted inventories of pine stands scheduled to undergo PCT to estimate potentially harvestable biomass. Inventories of stands in the 5- to 7-year-old and the 8- to 12-year-old age groups showed average volumes of 14.47 and 39.63 green tons per acre of biomass, respectively. Results suggest that PCT stands in the 8- to 12-yearold age group may contain sufficient volumes for economically feasible harvests based on removal estimations, thinning costs, and regional biomass prices. The feasibility of such harvests will largely depend on the degree to which harvesting costs are affected by utilizing the small-diameter stems typically found in PCT stands and local demand for biomass.
To read the full article please visit the link below:
Hanzelka, Nathan C., Jay Sullivan, M. Chad Bolding, and Scott M. Barrett. 2016. “Economic Feasibility of Utilizing Precommercially Thinned Southern Pine as a Woody Biomass Energy Source.” Forest Products Journal 66 (5–6): 354–61. https://doi.org/10.13073/FPJ-D-15-00041.
by Dr. Molly Darr | May 24, 2022 | 2011-2020 Publications, Southern Pine Beetle
Abstract
Two conservation goals of the early 20th century, extensive reforestation and reduced wildfire through fire exclusion, may have contributed to declining pollinator abundance as forests became denser and shrub covered. To examine how forest structure affects bees we selected 5 stands in each of 7 forest types including: cleared forest; dense young pines; thinned young pines; mature open pine with extensive shrub/sapling cover; mature open pine with extensive herbaceous plant cover and little shrub cover; mature upland hardwood forest; and mature riparian hardwood forest. We sampled bees during the 2008 growing season using pan traps and measured overstory tree density, understory herbaceous plant and shrub diversity and cover, light penetration, and leaf area index. Numbers of bees and numbers of species per plot were highest in cleared forest and in mature pine stands with an herbaceous plant understory. Estimates of asymptotic species richness were highest in mature riparian hardwood forests, cleared forests and open pine forests with an herbaceous plant understory. Bee communities in the cleared forests and in the mature pine with an herbaceous plant understory were grouped together in ordination space which was consistent with perMANOVA results. The best predictor variable for bee species density was total tree basal area which was negatively correlated (r2 = 0.58), while the best model for predicting bee abundance (r2 = 0.62) included canopy openness, plant species density (both positively correlated) and shrub cover (negatively correlated). Our results combined with many others show that thinning forests combined with shrub control provides good bee habitat, is compatible with habitat restoration and management for other species, and the resulting forests will be healthier and less susceptible to old (e.g., southern pine beetle, Dendroctonus frontalis) and new (European woodwasp, Sirex noctilio) threats.
Keywords
Apoidea. Pollinator decline, Forest cover, Native bees, Solitary bees, Forest health
To read the full article please visit the link below:
Hanula, James L., Scott Horn, and Joseph J. O’Brien. 2015. “Have Changing Forests Conditions Contributed to Pollinator Decline in the Southeastern United States?” Forest Ecology and Management 348 (July): 142–52. https://doi.org/10.1016/j.foreco.2015.03.044.
by Dr. Molly Darr | May 24, 2022 | 2011-2020 Publications, Southern Pine Beetle
Abstract
Body size is a key biological trait frequently used to assess fitness. Variation in body size stems from genetic and environmental factors and can have strong affects on reproduction. Here, we quantify narrow-sense heritability of size, fecundity, and sexual size dimorphism in four bark beetle species across two genera: Ips pini (Say), Ips lecontei Swaine, Dendroctonus frontalis Zimmermann, and Dendroctonus brevicomis LeConte. For each species, we conducted rearing experiments pairing parents of large or small size classes and measuring body length of all progeny. There was significant narrow-sense heritability of body size in Ips, but not Dendroctonus. Male parent size in I. pini, I. lecontei, and D. frontalis was positively correlated with progeny production and female parent size was positively correlated with gallery length in I. pini, D. frontalis, and D. brevicomis. All species exhibited sexual size dimorphism (SSD), with males being larger than females (male-biased SSD) in Ips and females larger than males (female-biased SSD) in Dendroctonus. Although mean differences in body length between sexes was small, ~1-2% for Ips and 2-4% for Dendroctonus, the pioneer sex (first colonizer) was statistically larger than the nonpioneer sex in all species. In addition, the pioneer sex displayed greater phenotypic variation in body length than the nonpioneer sex, and Dendroctonus exhibited greater phenotypic variation in body length than Ips. Differing selection pressures within species and even between sexes likely affect body size and heritability patterns exhibited by bark beetles.
Keywords
Dendroctonus brevicomis, Dendroctonus frontalis, Ips lecontei, Ips pini, size
To read the full article please visit the link below:
Foelker, C. J., and R. W. Hofstetter. 2014. “Heritability, Fecundity, and Sexual Size Dimorphism in Four Species of Bark Beetles (Coleoptera: Curculionidae: Scolytinae).” Annals of the Entomological Society of America 107 (1): 143–51. https://doi.org/10.1603/AN12153.
by Dr. Molly Darr | May 24, 2022 | 2011-2020 Publications, Southern Pine Beetle
Abstract
Temperature has strong effects on metabolic processes of individuals and demographics of populations, but effects on ecological communities are not well known. Many economically and ecologically important pest species have obligate associations with other organisms; therefore, effects of temperature on these species might be mediated by strong interactions. The southern pine beetle (Dendroctonus frontalis Zimmermann) harbors a rich community of phoretic mites and fungi that are linked by many strong direct and indirect interactions, providing multiple pathways for temperature to affect the system. We tested the effects of temperature on this community by manipulating communities within naturally infested sections of pine trees. Direct effects of temperature on component species were conspicuous and sometimes predictable based on single-species physiology, but there were also strong indirect effects of temperature via alteration of species interactions that could not have been predicted based on autecological temperature responses. Climatic variation, including directional warming, will likely inßuence ecological systems through direct physiological effects as well as indirect effects through species interactions.
Keywords
species interactions, indirect interactions, climate change, community structure, physiological ecology
To read the full article please visit the link below:
Evans, L. M., R. W. Hofstetter, M. P. Ayres, and K. D. Klepzig. 2011. “Temperature Alters the Relative Abundance and Population Growth Rates of Species Within the Dendroctonus Frontalis (Coleoptera: Curculionidae) Community.” Environmental Entomology 40 (4): 824–34. https://doi.org/10.1603/EN10208.
