by Dr. Molly Darr | Jun 7, 2022 | 2011-2020 Publications
Abstract
In southern Mexico and Central America, the southern pine beetle Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae) commonly colonizes host trees simultaneously with Dendroctonus mesoamericanus Armendariz-Toledano and Sullivan, a recently described sibling species. We hypothesized that cross-species pheromone responses by host-seeking beetles might mediate joint mass attack, bole partitioning, and reproductive isolation between the species. Previous studies had indicated that D. frontalis females produce frontalin and that female D. mesoamericanus produce frontalin, endo-brevicomin, and ipsdienol (males of
both species produce endo-brevicomin and possibly ipsdienol). In field trapping trials in the Mexican state of Chiapas, D. frontalis was attracted to the lure combination of turpentine and racemic frontalin; racemic endo-brevicomin enhanced this response. In a single test, D. mesoamericanus was attracted in low numbers to the combination of turpentine, racemic frontalin, and racemic endo-brevicomin after the addition of racemic ipsdienol; in contrast, racemic ipsdienol reduced responses of D. frontalis. Inhibition of D. frontalis was generated in both sexes by (þ)- and racemic ipsdienol, but by (-)-ipsdienol only in females. Logs infested with D. mesoamericanus females (the pioneer sex in Dendroctonus) attracted both species in greater numbers than either D. frontalis female-infested or uninfested logs. Our data imply that D. frontalis may be more attracted to pioneer attacks of D. mesoamericanus females, and that this could be owing to the presence of endo-brevicomin in the latter. Possible intra- and inter-specific functions of semiochemicals investigated in our experiments are discussed.
Keywords
coexistence, bark beetle, reproductive isolation, syntopic species, pheromone
To read the full article please visit the link below:
Nino-Dominguez, Alicia, Brian T. Sullivan, Jose H. Lopez-Urbina, and Jorge E. Macias-Samano. 2016. “Responses by Dendroctonus Frontalis and Dendroctonus Mesoamericanus ( Coleoptera: Curculionidae) to Semiochemical Lures in Chiapas, Mexico: Possible Roles of Pheromones During Joint Host Attacks.” Journal of Economic Entomology 109 (2): 724 31. https://doi.org/10.1093/jee/tov406.
by Dr. Molly Darr | Jun 7, 2022 | 2011-2020 Publications
Abstract
Forest insect pest disturbance is increasing in certain areas of North America as many insect species, such as the southern pine beetle, expand their range due to a warming climate. Because insect pests are beginning to
occupy forests that are managed for multiple uses and have not been managed for pests before, it is becoming increasingly important to determine how forests should be managed for pests when non-timber ecosystem services are considered in addition to traditional costs and revenues. One example of a service that is increasingly considered in forest management and that may affect forest pest management is carbon sequestration. This manuscript seeks to understand whether the incorporation of forest carbon sequestration into cost-benefit analysis of different forest pest management strategies affects the financially optimal
strategy. We examine this question through a case study of the southern pine beetle (SPB) in a new area of SPB expansion, the New Jersey Pinelands National Reserve (NJPR). We utilize a forest ecology and economics model and include field data from the NJPR as well as outbreak probability statistics from previous years. We find under the majority of scenarios, incorporating forest carbon sequestration shifts the financially optimal SPB management strategy from preventative thinning toward no management or reactionary management in forest stands in New Jersey. These results contradict the current recommended treatment strategy for SPB and signify that the inclusion of multiple ecosystem services into a cost-benefit analysis may drastically alter which pest management strategy is economically optimal.
Keywords
Forest pest management, Southern pine beetle, Carbon sequestration, Forest thinning
To read the full article please visit the link below:
Niemiec, Rebecca M., David A. Lutz, and Richard B. Howarth. 2014. “Incorporating Carbon Storage into the Optimal Management of Forest Insect Pests: A Case Study of the Southern Pine Beetle (Dendroctonus Frontalis Zimmerman) in the New Jersey Pinelands.” Environmental Management 54 (4): 875–87. https://doi.org/10.1007/s00267-014-0304-0.
by Dr. Molly Darr | Jun 7, 2022 | 2011-2020 Publications, Southern Pine Beetle
Abstract
Southern pine beetle (SPB) (Dendroctonus frontalis Zimm) outbreaks and wildfire occurrence in recent decades has triggered growing concerns regarding their possible interactions. However, few studies have quantified the fuel characteristics of SPB-killed stands, especially the dynamics of the resulting fuel complex. More importantly, how changes in the fuel complex will affect fire behavior remains unclear. Using field measurements in combination with fire modeling systems, we studied fuel dynamics and its implication to potential fire behaviors by sampling non-outbreak, early post-outbreak (2–3 years), and late post-outbreak (7 8 years) loblolly pine-dominated stands in Georgia and South Carolina, USA. We found that the loadings of 1-hr, 10-hr, 100-hr, 1000-hr fuels, and litter depth were significantly greater in post-outbreak stands than in non-outbreak stands. Stand structure was altered in post-outbreak stands, which contained fewer live pines and more hardwoods. We used the Fuel Characteristic Classification System (FCCS) combined with actual data to construct representative fuel beds from the field data. These customized fuel beds were then used to model surface fire behavior that could be altered by the changes in fuel loading and stand structure resulting from SPB outbreaks. Both FCCS and BehavePlus fire modeling systems predicted a faster rate of spread and longer flame lengths in post-outbreak stands than in non-outbreak stands. Late post-outbreak stands under extremely dry conditions were predicted to have the most extreme fire behavior. Our results fill a critical knowledge gap, which will help forest managers make informed decisions on the management of loblolly pine-dominated stands after the southern pine beetle outbreak.
Keywords
Fuel dynamics, Fire behavior. Loblolly-dominated forests. Southern pine beetle outbreaks, Piedmont
To read the full article please visit the link below:
Xie, Hongtao, Jennifer E. Fawcett, and G. Geoff Wang. 2020. “Fuel Dynamics and Its Implication to Fire Behavior in Loblolly Pine-Dominated Stands after Southern Pine Beetle Outbreak.” Forest Ecology and Management 466 (June): 118130. https://doi.org/10.1016/j.foreco.2020.118130.
by Dr. Molly Darr | Jun 6, 2022 | 2021-Present Publications
Abstract
Forest biotic populations and communities are undergoing irreversible changes due to climatic perturbations, and these effects may be exacerbated by insect pests. In the southeastern United States (U.S.), Dendroctonus frontalis is one of the most important forest pests that can cause substantial tree mortality over large geographic areas. As life-history of D. frontalis is dependent on environmental conditions, our objective was to determine the effects of climatic variables on the species occurrence of D. frontalis and their main predator, Thanasimus dubius. U.S. Department of Agriculture – Forest Service beetle trapping data (proxy for true abundance) for 2014–2018 were assessed with nine climatic variables including: (1) average monthly minimum, maximum, and mean temperatures; (2) mean winter temperature; (3) minimum, maximum and mean annual temperature; and (4) cumulative winter and annual precipitation. Variable selection was performed using least absolute selection and shrinkage operator (LASSO), and selected variables were fit to varying coefficient generalized additive models (GAMs). Minimum temperatures for February and March and maximum temperatures for January and prior year August were found to have a significant effect on D. frontalis numbers, and model accuracy was ~89%. Beetle suitability was assessed for 1981–2100 under three different shared socioeconomic pathways (SSP). The model indicated that the suitability of D. frontalis has increased from 1981 to 2019 in certain regions of Alabama, Mississippi, and Georgia, while Arkansas, Kentucky, Louisiana, North Carolina, Tennessee, East Texas, and Virginia had low suitability. Future projections indicated comparable D. frontalis numbers to current numbers under the lowest SSP of 2.1◦C by year 2100, but D. frontalis may decrease under higher warming projections. The same climatic predictors influenced T. dubius, except average September maximum temperature replaced August maximum temperatures in the model. Understanding how these abiotic factors influence forest pest populations may better guide
Keywords
Bark beetle, Climate change, Disturbance, Pinus, Predator, Range expansion, Southern pine beetle
To read the full article please visit the link below:
Munro, Holly L., Cristian R. Montes, Stephen M. Kinane, and Kamal J. K. Gandhi. 2021. “Through Space and Time: Predicting Numbers of an Eruptive Pine Tree Pest and Its Predator under Changing Climate Conditions.” Forest Ecology and Management 483 (March): 118770. https://doi.org/10.1016/j.foreco.2020.118770.
by Dr. Molly Darr | May 25, 2022 | 2021-Present Publications, Southern Pine Beetle
To read the full article please visit the link below:
Munro, Holly L., Kamal J. K. Gandhi, Brittany F. Barnes, Cristian R. Montes, John T. Nowak, William P. Shepherd, Caterina Villari, and Brian T. Sullivan. 2021. “Electrophysiological and Behavioral Responses Dendroctonus Frontalis and D. Terebrans (Coleoptera: Curculionidae) to Resin Odors of Host Pines (Pinus Spp.) (Vol 30, Pg 215, 2020).” Chemoecology 31 (1): 75–75. https://doi.org/10.1007/s00049-020-00328-y.
