by Dr. Molly Darr | Jun 15, 2022 | 2011-2020 Publications
Abstract
The southern pine beetle (SPB) is the most important biotic disturbance in southern pine forests and causes extensive changes to the forest environment. In this chapter we provide an overview of the ecological impacts of the SPB on forest conditions (the state of the forest) and on forest resources (uses and values associated with the forest). We define ecological impact as the effects—positive or negative—of SPB activities on the forest ecosystem. The impact on forest conditions is the result of widespread tree mortality, which affects ecological processes such as: primary production, nutrient cycling, forest succession, and forest composition and configuration. We discuss how the SPB affects these ecological processes through modification of the physical environment and the temporal distribution of resources. For the ecological impact on forest resources, we emphasize the impacts of SPB on resources that are affected from an ecological point of view (e.g., hydrology and wildlife). Changes in forest structure resulting from SPB herbivory can modify key hydrologic processes that control the quantity and quality of water reaching a stream. The ecological impacts of the SPB on wildlife are the result of changes in the distribution and abundance of plant species and insect populations. Increases in SPB densities directly affect the food available for insectivore birds, mainly bark-foraging woodpeckers. The impacts on wildlife have been deduced from changes in wildlife habitat as a result of SPB infestations. An approach to estimate the impacts of SPB herbivory on wildlife habitat in a forest landscape is introduced.
Keywords
biotic disturbance, ecological impact, forest succession, hydrology, nutrient cycling, primary production, wildlife habitat
To read the full article please visit the link below:
Tchakerian, Maria D., and Robert N. Coulson. 2011. “Ecological Impacts of Southern Pine Beetle.” U S Forest Service General Technical Report SRS 140: 223–34.
by Dr. Molly Darr | Jun 15, 2022 | 2011-2020 Publications
Abstract
We evaluated the response of amphibians and reptiles to two levels of prescribed burning and three levels of thinning using a field experiment consisting of a before–after, control-impact, and factorial complete block design over a four year period in the William B. Bankhead National Forest located in northwestern Alabama. We captured 2643 individuals representing 47 species (20 amphibians and 27 reptiles) during 3132 trap nights. Pre-treatment captures varied widely for both amphibians and reptiles among the stands designated for management, which was likely due to forest structural changes caused by tree mortality resulting from Southern Pine Beetle (Dendroctonus frontalis) infestations. Within each amphibian and reptile species assemblage, we observed species-specific associations with specific treatments and environmental characteristics. In regards to individual species responses, Eastern Fence Lizards (Sceloporus undulatus) increased in thin-with-burn treatments and Green Anoles (Anolis carolinensis) tended to increase in all thinned stands. North American Racers (Coluber constrictor) increased in thin-only plots primarily during the second post-treatment year. Mississippi Slimy Salamander (Plethodon mississippi) captures tended to decrease in all treatment stands throughout the study period, which may been due to either drier environmental conditions during post-treatment sampling or natural population cycling. Pool-breeding amphibian captures were more likely related to the hydroperiod of aquatic breeding environments within 290 m of survey locations rather than forest treatments. Our results illustrate that forest restoration through tree thinning can positively influence certain reptile species with limited impacts on amphibians in upland, pine-dominated forests of northern Alabama. However, as our forest stands are scheduled to be burned every 3–5 years, continued monitoring is necessary to understand the impacts of repeated disturbances.
Keywords
Herpetofauna, William B. Bankhead National Forest, Forest management, Southern Pine Beetle, Disturbance, Canonical correspondence analysis
To read the full article please visit the link below:
Sutton, William B., Yong Wang, and Callie J. Schweitzer. 2013. “Amphibian and Reptile Responses to Thinning and Prescribed Burning in Mixed Pine-Hardwood Forests of Northwestern Alabama, USA.” Forest Ecology and Management 295 (May): 213–27. https://doi.org/10.1016/j.foreco.2012.12.047.x
by Dr. Molly Darr | Jun 15, 2022 | 2021-Present Publications
Abstract
The southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae), is among the most destructive bark beetle pests of pines (Pinaceae) of the southeast and mid-Atlantic United States of America, Mexico, and Central America. Numerous volatile compounds can stimulate or reduce attraction of the beetle, but efforts to incorporate these into effective, practical technologies for pest management have yielded mixed results. Attractants have been incorporated into lures used in monitoring traps that are employed operationally to forecast outbreaks and detect emerging populations. The attraction inhibitor, verbenone, shows efficacy for suppressing southern pine beetle infestations but has not yet been adopted operationally. No effective semiochemical tree protectant has been developed for the beetle. We discuss complexities in the chemical ecology of the beetle that likely have impeded research and development of semiochemical management tools, and we describe basic science gaps that may hinder further progress if not addressed. We also report some supporting, original experimental data indicating (1) that a verbenone device can inhibit the beetle’s response to sources of attractant in a radius of at least several metres, (2) similar olfactory responses by the beetle to both enantiomers of verbenone, and (3) that pheromone background can cause conflicting results in semiochemical field tests.
To read the full article please visit the link below:
Sullivan, Brian T., and Stephen R. Clarke. 2021. “Semiochemicals for Management of the Southern Pine Beetle (Coleoptera: Curculionidae: Scolytinae): Successes, Failures, and Obstacles to Progress.” Canadian Entomologist 153 (1): 36–61. https://doi.org/10.4039/tce.2020.67.
by Dr. Molly Darr | Jun 15, 2022 | 2021-Present Publications
Abstract
The southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae) is a major destructive pest of Pinus L. In the southeastern United States, numbers of this species and a major predator, Thanasimus dubius (Fabricius) (Coleoptera: Cleridae), captured during an annual springtime trapping survey are used to make forecasts of the likelihood and severity of an outbreak during the following summer. We investigated responses by both species to six lure formulations to evaluate their suitability for the survey and allow integration of historical data sets produced with differing lure compositions. Trapping trials were performed at four locations across three states (Louisiana, Mississippi, and Alabama) during spring, and at these and one additional location (North Carolina) in fall 2016. All lures included the pheromone component frontalin. Southern pine beetle preferred lures that additionally included the pheromone component endo-brevicomin and turpentine as a source of host odors (rather than a 7:3 mixture of monoterpenes alpha- and beta pinene). Thanasimus dubius displayed little discrimination among lure compositions. Lure preferences by southern pine beetle did not differ significantly among locations in spring but were influenced by season. Gas chromatography (GC)-electroantennographic detection analyses with southern pine beetle and GC-mass spectrometry identified numerous known and potential semiochemicals that distinguished volatiles released by the tested host odor devices. The lure combination that included endo-brevicomin and alpha/beta-pinene is recommended for the trapping survey because of its high sensitivity for southern pine beetle and potential for greater data integrity resulting from its reproducible composition.
Keywords
bark beetle, forecast, host odor, monoterpene, pheromone
To read the full article please visit the link below:
Sullivan, Brian T., William P. Shepherd, John T. Nowak, Stephen R. Clarke, Paul R. Merten, Ronald F. Billings, William W. Upton, John J. Riggins, and Cavell Brownie. 2021. “Alternative Formulations of Trap Lures for Operational Detection, Population Monitoring, and Outbreak Forecasting of Southern Pine Beetle in the United States.” Journal of Economic Entomology 114 (3): 1189–1200. https://doi.org/10.1093/jee/toab062.
by Dr. Molly Darr | Jun 15, 2022 | 2011-2020 Publications
Abstract
The southern pine beetle Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae) is attracted to an aggregation pheromone that includes the multifunctional pheromone component endo-brevicomin. The effect of endo-brevicomin on attractive lures varies from strong enhancement to reduction of beetle attraction depending upon release rate, lure component spacing, and proximity of beetle infestations. Anecdotal observations have further suggested that the effects of endo-brevicomin vary during the year. We investigated this possibility under non-outbreak conditions in southwestern Mississippi where for two-and-a-half years we monitored traps baited with frontalin and the host odor alpha-pinene either (a) alone, or with an endo-brevicomin release device either (b) located directly on the trap, or (c) displaced 6m away. The endo-brevicomin devices in our tests increased D. frontalis catches during all times of year, and 6m displacement of the endo-brevicomin release device from the trap did not significantly alter responses except during the spring flight peak when displacement increased catches. Our data suggest that flying D. frontalis have a stronger tendency to avoid the immediate proximity of a release point of endo-brevicomin during their springtime dispersal flight when catches are greatest. Catches of Thanasimus dubius (F.) (Coleoptera: Cleridae), a major predator of D. frontalis, were not altered by endo-brevicomin, and ratios of D. frontalis to T. dubius changed over the course of the year. We discuss the possible effects of intra-annual variation in D. frontalis response to endo-brevicomin both on beetle attack behavior and use of endo-brevicomin as a lure adjuvant in D. frontalis population monitoring.
Keywords
monitoring, bark beetle, trapping, pheromone, phenology
To read the full article please visit the link below:
Sullivan, Brian T., Cavell Brownie, and JoAnne P. Barrett. 2016. “Intra-Annual Variation in Responses by Flying Southern Pine Beetles (Coleoptera: Curculionidae: Scolytinae) to Pheromone Component Endo-Brevicomin.” Journal of Economic Entomology 109 (4): 1720–28. https://doi.org/10.1093/jee/tow078.
