Current Research

Population biology of biological invasions

Much of my research focuses on understanding ecological processes operating during the arrival, establishment, and spread phases of biological invasions. In particular, I am interested in understanding these processes as the basis for more effective strategies to exclude invaders, prevent establishment (eradication) and contain the spread of invading forest pests. This work includes studies on the gypsy moth, Sirex woodwasp, beech bark disease, Japanese oak wilt disease, emerald ash borer and hemlock woolly adelgid.

Forest insect population dynamics

I am interested in understanding the processes that are responsible for the spatial and temporal patterns of forest insect outbreaks. Many insect species exhibit periodic population oscillations that occur synchronously over large areas but we have only a partial understanding of the population processes (interactions with predators, parasitoids, host plants and disease) that cause these patterns. Analyses of historical data and mathematical models are applied to explore these relationships. This work focuses on the gypsy moth, but includes several other forest insect species as well.

Why This Research is Important

North America is currently experiencing an onslaught of invasions by damaging forest pest species. We need to develop more effective strategies for mitigating this problem. Unfortunately, there are often few options for preventing or minimizing the impacts of these invasions but the development of a clearer understanding of the invasion process is critical for the development of more effective management strategies.

Forest insect outbreaks have a multitude of ecological and economic impacts but currently we have a very limited ability to either predict or prevent such outbreaks. Knowledge of the underlying processes that generate outbreaks is critical for improving our ability to forecast and manage outbreaks in the future.

Education

• University of Massachusetts, Postdoctoral 1988
• University of California at Berkeley, Ph.D. Entomology 1984
• Allegheny College, B.S. Biology 1978

Professional Organizations

• West Virginia University, Adjunct Faculty (1992 - )
• Invasive Species Specialist Group (ISSG). World Conservation Union (IUCN), Elected Member (2005 - )
• IUFRO Research Group 7.03.00, Entomology, Coordinator (2005 - )
• Carnegie Museum of Natural History, Pittsburgh, PA, Research Associate (1995 - )
• Population Ecology, Editorial Board (2005 - )
• Ecology Letters, Editorial Board (2010 - )
• Biological Invasions, Editorial Board (2013 - )
• The Pennsylvania State University, Adjunct Faculty (2003 - )

Awards & Recognition

Featured Publications & Products

• Epanchin-Niell, Rebecca S.; Haight, Robert G.; Berec, Ludek; Kean, John M.; Liebhold, Andrew M. 2012. Optimal surveillance and eradication of invasive species in heterogeneous landscapes.
• Epanchin-Niell, Rebecca S.; Liebhold, Andrew M. 2015. Benefits of invasion prevention: Effect of time lags, spread rates, and damage persistence.
• Liebhold, Andrew M.; McCullough, Deborah G.; Blackburn, Laura M.; Frankel, Susan J.; Von Holle, Betsy; Aukema, Juliann E. 2013. A highly aggregated geographical distribution of forest pest invasions in the USA.
• Tobin, Patrick C.; Berec, Ludek; Liebhold, Andrew M. 2011. Exploiting Allee effects for managing biological invasions.
• Liebhold, Andrew M.; Brockerhoff, Eckehard G.; Kimberley, Mark; Beggs, Jacqueline. 2017. Depletion of heterogeneous source species pools predicts future invasion rates.
• Liebhold, Andrew M.; Brockerhoff, Eckehard G.; Kalisz, Susan; Nuñez, Martin A.; Wardle, David A.; Wingfield, Michael J. 2017. Biological invasions in forest ecosystems.

Publications

• Machta, Jonathan ; Blackwood, Julie C.; Noble, Andrew ; Liebhold, Andrew M.; Hastings, Alan . 2019. A Hybrid Model for the Population Dynamics of Periodical Cicadas.
• Liebhold, Andrew M. 2019. Air pollution as an experimental probe of insect population dynamics.
• Fei, Songlin ; Morin, Randall S.; Oswalt, Christopher M.; Liebhold, Andrew M. 2019. Biomass losses resulting from insect and disease invasions in US forests.
• Yamaguchi, Ryo ; Yamanaka, Takehiko ; Liebhold, Andrew M. 2019. Consequences of hybridization during invasion on establishment success.
• Liebhold, Andrew M.; Kean, John M. 2019. Eradication and containment of non-native forest insects: successes and failures.
• Mech, Angela M.; Thomas, Kathryn A.; Marsico, Travis D.; Herms, Daniel A.; Allen, Craig R.; Ayres, Matthew P.; Gandhi, Kamal J. K.; Gurevitch, Jessica ; Havill, Nathan P.; Hufbauer, Ruth A.; Liebhold, Andrew M.; Raffa, Kenneth F.; Schulz, Ashley N.; Uden, Daniel R.; Tobin, Patrick C. 2019. Evolutionary history predicts high impact invasions by herbivorous insects.
• Gippet, Jérôme M.W.; Liebhold, Andrew M.; Fenn-Moltu, Gyda ; Bertelsmeier, Cleo . 2019. Human-mediated dispersal in insects.
• Haynes, Kyle J.; Walter, Jonathan A.; Liebhold, Andrew M. 2019. Population spatial synchrony enhanced by periodicity and low detuning with environmental forcing.
• Goldstein, Joshua ; Park, Jaewoo ; Haran, Murali ; Liebhold, Andrew ; Bjørnstad, Ottar N. 2019. Quantifying spatio-temporal variation of invasion spread.
• Ward, Samuel F.; Fei, Songlin ; Liebhold, Andrew M. 2019. Spatial patterns of discovery points and invasion hotspots of non native forest pests.
• Guo, Qinfeng ; Fei, Songlin ; Potter, Kevin M.; Liebhold, Andrew M.; Wen, Jun . 2019. Tree diversity regulates forest pest invasion.
• Blackwood, Julie C.; Machta, Jonathan ; Meyer, Alexander D.; Noble, Andrew E.; Hastings, Alan ; Liebhold, Andrew M. 2018. Competition and Stragglers as Mediators of Developmental Synchrony in Periodical Cicadas.
• Osada, Yutaka ; Yamakita, Takehisa ; Shoda-Kagaya, Etsuko ; Liebhold, Andrew M.; Yamanaka, Takehiko . 2018. Disentangling the drivers of invasion spread in a vector-borne tree disease.
• Haynes, Kyle J.; Liebhold, Andrew M.; Bjørnstad, Ottar N.; Allstadt, Andrew J.; Morin, Randall S. 2018. Geographic variation in forest composition and precipitation predict the synchrony of forest insect outbreaks.
• Chase, Kevin ; Stringer, Lloyd ; Butler, Ruth ; Liebhold, Andrew ; Miller, Daniel ; Shearer, Peter ; Brockerhoff, Eckehard G. 2018. Multiple-lure surveillance trapping for ips bark beetles, monochamus longhorn beetles, and halyomorpha halys (hemiptera: pentatomidae).
• Liebhold, Andrew M.; Yamanaka, Takehiko ; Roques, Alain ; Augustin, Sylvie ; Chown, Steven L.; Brockerhoff, Eckehard G.; Pyšek, Petr . 2018. Plant diversity drives global patterns of insect invasions.
• Bertelsmeier, Cleo ; Ollier, Sébastien ; Liebhold, Andrew M.; Brockerhoff, Eckehard G.; Ward, Darren ; Keller, Laurent . 2018. Recurrent bridgehead effects accelerate global alien ant spread.
• Morin, Randall S.; Gottschalk, Kurt W.; Ostry, Michael E.; Liebhold, Andrew M. 2018. Regional patterns of declining butternut (Juglans cinerea L.) suggest site characteristics for restoration.
• Santini, Alberto; Liebhold, Andrew; Migliorini, Duccio; Woodward, Steve. 2018. Tracing the role of human civilization in the globalization of plant pathogens.
• Klapwijk, Maartje J.; Walter, Jonathan A.; Hirka, Anikó ; Csóka, György ; Björkman, Christer ; Liebhold, Andrew M. 2018. Transient synchrony among populations of five foliage-feeding Lepidoptera.
• Koenig, Walter D.; Liebhold, Andrew M. 2017. A decade of emerald ash borer effects on regional woodpecker and nuthatch populations.
• Liebhold, Andrew M.; Brockerhoff, Eckehard G.; Nuñez, Martin A. 2017. Biological invasions in forest ecosystems: a global problem requiring international and multidisciplinary integration.
• Nunez-Mir, Gabriela C.; Liebhold, Andrew M.; Guo, Qinfeng; Brockerhoff, Eckehard G.; Jo, Insu; Ordonez, Kimberly; Fei, Songlin. 2017. Biotic resistance to exotic invasions: its role in forest ecosystems, confounding artifacts, and future directions.
• Brockerhoff, E.G.; Liebhold, A.M. 2017. Ecology of forest insect invasions.
• Hartl-Meier, Claudia ; Esper, Jan ; Liebhold, Andrew ; Konter, Oliver ; Rothe, Andreas ; Büntgen, Ulf . 2017. Effects of host abundance on larch budmoth outbreaks in the European Alps.
• Büntgen, Ulf; Greuter, Lucie; Bollmann, Kurt; Jenny, Hannes; Liebhold, Andrew; Galván, J. Diego; Stenseth, Nils C.; Andrew, Carrie; Mysterud, Atle. 2017. Elevational range shifts in four mountain ungulate species from the Swiss Alps.
• ​Kauffman, Bruce W.; Clatterbuck, Wayne K.; Liebhold, Andrew M.; Coyle, David R. 2017. Gypsy moth in the southeastern U.S.: Biology, ecology, and forest management strategies.
• Ricciardi, Anthony; Blackburn, Tim M.; Carlton, James T.; Dick, Jaimie T.A.; Hulme, Philip E.; Iacarella, Josephine C.; Jeschke, Jonathan M.; Liebhold, Andrew M.; Lockwood, Julie L.; MacIsaac, Hugh J.; Pyšek, Petr; Richardson, David M.; Ruiz, Gregory M.; Simberloff, Daniel; Sutherland, William J.; Wardle, David A.; Aldridge, David C. 2017. Invasion Science: A Horizon Scan of Emerging Challenges and Opportunities.
• Chase, Kevin, D..; Kelly, Dave; Liebhold, Andrew M.; Bader, Martin K.-F.; Brockerhoff, Eckehard G. 2017. Long-distance dispersal of non-native pine bark beetles from host resources.
• Bittner, Tonya D.; Hajek, Ann E.; Liebhold, Andrew M.; Thistle, Harold; Cullen, Dan. 2017. Modification of a pollen trap design to capture airborne conidia of Entomophaga maimaiga and detection of conidia by quantitative PCR.
• Lantschner, Maria Victoria; Atkinson, Thomas H.; Corley, Juan C.; Liebhold, Andrew M. 2017. Predicting North American Scolytinae invasions in the Southern Hemisphere.
• Blackburn, Laura; Epanchin-Niell, Rebecca; Thompson, Alexandra; Liebhold, Andrew; Beggs, Jacqueline. 2017. Predicting costs of alien species surveillance across varying transportation networks.
• Hudgins, Emma J.; Liebhold, Andrew M.; Leung, Brian; Early, Regan. 2017. Predicting the spread of all invasive forest pests in the United States.
• Bertelsmeier, Cleo; Ollier, Sébastien; Liebhold, Andrew; Keller, Laurent. 2017. Recent human history governs global ant invasion dynamics.
• Morin, Randall S.; Liebhold, Andrew M.; Pugh, Scott A.; Crocker, Susan J. 2017. Regional assessment of emerald ash borer, Agrilus planipennis, impacts in forests of the Eastern United States.
• Walter, Jonathan A.; Sheppard, Lawrence W.; Anderson, Thomas L.; Kastens, Jude H.; Bjørnstad, Ottar N.; Liebhold, Andrew M.; Reuman, Daniel C.; Blasius, Bernd. 2017. The geography of spatial synchrony.
• Krivan, Vlastimil; Lewis, Mark; Bentz, Barbara J.; Bewick, Sharon; Lenhart, Suzanne M.; Liebhold, Andrew. 2016. A dynamical model for bark beetle outbreaks.
• Liebhold, Andrew M.; Berec, Ludek; Brockerhoff, Eckehard G.; Epanchin-Niell, Rebecca S.; Hastings, Alan; Herms, Daniel A.; Kean, John M.; McCullough, Deborah G.; Suckling, David M.; Tobin, Patrick C.; Yamanaka, Takehiko. 2016. Eradication of Invading Insect Populations: From Concepts to Applications.
• Castedo-Dorado, Fernando ; Lago-Parra, Gorka ; Lombardero, María J.; Liebhold, Andrew M.; Álvarez-Taboada, María F. 2016. European gypsy moth (Lymantria dispar dispar L.) completes development and defoliates exotic radiata pine plantations in Spain.
• Tisseuil, Clement; Gryspeirt, Aiko; Lancelot, Renaud; Pioz, Maryline; Liebhold, Andrew; Gilbert, Marius. 2016. Evaluating methods to quantify spatial variation in the velocity of biological invasions.
• Liebhold, Andrew M.; Yamanaka, Takehiko; Roques, Alain; Augustin, Sylvie; Chown, Steven L.; Brockerhoff, Eckehard G.; Pysek, Petr. 2016. Global compositional variation among native and non-native regional insect assemblages emphasizes the importance of pathways.
• Morin, Randall S.; Liebhold, Andrew M. 2016. Invasive forest defoliator contributes to the impending downward trend of oak dominance in eastern North America.
• Lovett, Gary M.; Weiss, Marissa; Liebhold, Andrew M.; Holmes, Tom; Leung, Brian; Lambert, Kathy-Fallon; Orwig, David A.; Campbell, Faith T.; Rosenthal, Jonathan; McCullough, Deborah G.; Wildova, Radka; Ayres, Matthew P.; Canham, Charles D.; Foster, David R.; LaDeau, Shannon L.; Weldy, Troy. 2016. Nonnative forest insects and pathogens in the United States: impacts and policy options.
• Weed, Aaron S.; Ayres, Matthew P.; Liebhold, Andrew M.; Billings, Ronald F. 2016. Spatio-temporal dynamics of a tree-killing beetle and its predator.
• Roques, Alain; Auger-Rozenberg, Marie-Anne; Blackburn, Tim M.; Garnas, Jeff; Pysek, Petr; Rabitsch, Wolfgang; Richardson, David M.; Wingfield, Michael J.; Liebhold, Andrew M.; Duncan, Richard P. 2016. Temporal and interspecific variation in rates of spread for insect species invading Europe during the last 200 years.
• Koenig, Walter D.; Liebhold, Andrew M. 2016. Temporally increasing spatial synchrony of North American temperature and bird populations.
• Liebhold, Andrew M.; Griffin, Robert L. 2016. The legacy of Charles Marlatt and efforts to limit plant pest invasions.
• Morin, Randall S.; Pugh, Scott A.; Liebhold, Andrew M.; Crocker, Susan J. 2015. A regional assessment of emerald ash borer impacts in the Eastern United States: ash mortality and abundance trends in time and space.
• Iannone III, Basil V.; Potter, Kevin M.; Guo, Qinfeng; Liebhold, Andrew M.; Pijanowski, Bryan C.; Oswalt, Christopher M.; Fei, Songlin. 2015. Biological invasion hotspots: a trait-based perspective reveals new sub-continental patterns.
• Elkinton, Joseph; Boettner, George; Liebhold, Andrew; Gwiazdowski, Rodger. 2015. Biology, spread, and biological control of winter moth in the eastern United States.
• Berec, Ludek; Kean, John M.; Epanchin-Niell, Rebecca; Liebhold, Andrew M.; Haight, Robert G. 2015. Designing efficient surveys: spatial arrangement of sample points for detection of invasive species.
• Tobin, Patrick; Liebhold, Andrew M.; Roberts, E. Anderson; Blackburn, Laura M. 2015. Estimating spread rates of non-native species: the gypsy moth as a case study.
• Morin, Randall S.; Liebhold, Andrew M. 2015. Invasions by two non-native insects alter regional forest species composition and successional trajectories.
• Iannone, Basil V.; Oswalt, Christopher M.; Liebhold, Andrew M.; Guo, Qinfeng; Potter, Kevin M.; Nunez-Mir, Gabriela C.; Oswalt, Sonja N.; Pijanowski, Bryan C.; Fei, Songlin; Bradley, Bethany. 2015. Region-specific patterns and drivers of macroscale forest plant invasions.
• Konter, Oliver; Esper, Jan; Liebhold, Andrew; Kyncl, Tomas; Schneider, Lea; Düthorn, Elisabeth; Buntgen, Ulf. 2015. Tree-ring evidence for the historical absence of cyclic larch budmoth outbreaks in the Tatra Mountains.
• Corley, Juan C.; Villacide, José M.; Liebhold, Andrew M. 2014. Can entomophagous nematodes slow the spread of invasive pest populations The case study of Beddingia siricidicola released for the management of Sirex noctilio.
• Siegert, Nathan W.; McCullough, Deborah G.; Liebhold, Andrew M.; Telewski, Frank W. 2014. Dendrochronological reconstruction of the epicenter and early spread of emerald ash borer in North America.
• Liebhold, Andrew; Wingfield, Michael. 2014. Globalization and its implications for forest health.
• ​Reilly, James R.; Hajek, Ann E.; Liebhold, Andrew M.; Plymale, Ruth. 2014. Impact of Entomophaga maimaiga (Entomophthorales: Entomophthoraceae) on outbreak gypsy moth populations (Lepidoptera: Erebidae): the role of weather.
• Li, Xiaoshu; Preisser, Evan L.; Boyle, Kevin J.; Holmes, Thomas P.; Liebhold, Andrew; Orwig, David. 2014. Potential social and economic impacts of the hemlock woolly adelgid in southern New England.
• Brockerhoff, Eckehard G.; Kimberley, Mark; Liebhold, Andrew M.; Haack, Robert A.; Cavey, Joseph F. 2014. Predicting how altering propagule pressure changes establishment rates of biological invaders across species pools.
• Tobin, Patrick C.; Gray, David R.; Liebhold, Andrew M. 2014. Supraoptimal temperatures influence the range dynamics of a non-native insect.
• Koenig, Walter E.; Liebhold, Andrew M. 2013. Avian predation pressure as a potential driver of periodical cicada cycle length.
• Trotter, R. Talbot; Morin, Randall S.; Oswalt, Sonja N.; Liebhold, Andrew. 2013. Changes in the regional abundance of hemlock associated with the invasion of hemlock woolly adelgid (Adelges tsugae Annand).
• Koenig, Walter D.; Liebhold, Andrew M.; Bonter, David N.; Hochachka, Wesley M.; Dickinson, Janis L. 2013. Effects of the emerald ash borer invasion on four species of birds.
• Liebhold, Andrew M.; Plymale, Ruth ; Elkinton, Joseph S.; Hajek, Ann E. 2013. Emergent fungal entomopathogen does not alter density dependence in a viral competitor.
• ​Allstadt, Andrew J.; Haynes, Kyle J.; Liebhold, Andrew M.; Johnson, Derek M. 2013. Long-term shifts in the cyclicity of outbreaks of a forest-defoliating insect.
• Britton, Kerry O.; Liebhold, Andrew M. 2013. One world, many pathogens!.
• Cuddington, K.; Fortin, M.-J.; Gerber, L.R.; Hastings, A.; Liebhold, A.; OConnor, M.; Ray, C. 2013. Process-based models are required to manage ecological systems in a changing world.
• Donovan, Geoffrey H.; Butry, David T.; Michael, Yvonne L.; Prestemon, Jeffrey P.; Liebhold, Andrew M.; Gatziolis, Demetrios; Mao, Megan Y. 2013. The relationship between trees and human health: evidence from the spread of the emerald ash borer.
• Tobin, Patrick C.; Blackburn, Laura M.; Gray, Rebecca H.; Lettau, Christopher T.; Liebhold, Andrew M.; Raffa, Kenneth F. 2013. Using delimiting surveys to characterize the spatiotemporal dynamics facilitates the management of an invasive non-native insect.
• ​Blackwood, Julie C.; Berec, Ludek; Yamanaka, Takehiko; Epanchin-Niell, Rebecca S.; Hastings, Alan; Liebhold, Andrew M. 2012. Bioeconomic synergy between tactics for insect eradication in the presence of Allee effects.
• Haynes, Kyle J.; Liebhold, Andrew M.; Johnson, Derek M. 2012. Elevational gradient in the cyclicity of a forest-defoliating insect.
• Liebhold, Andrew M. 2012. Forest pest management in a changing world.
• Haynes, K.yle J.; Bjornstad, Ottar N.; Allstadt, Andrew J.; Liebhold, Andrew M. 2012. Geographical variation in the spatial synchrony of a forest-defoliating insect: isolation of environmental and spatial drivers.
• Liebhold, Andrew M.; Brockerhoff, Eckehard G.; Garrett, Lynn J.; Parke, Jennifer L. 2012. Live plant imports: the major pathway for forest insect and pathogen invasions of the US.
• Liebhold, A.M.; Haynes, K.J.; Bjørnstad, O.N. 2012. Spatial synchrony of insect outbreaks.
• Pugh, Scott A.; Liebhold, Andrew M.; Morin, Randall S. 2011. Changes in ash tree demography associated with emerld ash borer invasion, indicated by regional forest inventory data from the Great Lakes States.
• Brockerhoff, Eckehard G.; Aukema, Juliann E.; Cavey, Joseph F.; Garrett, Lynn J.; Haack, Robert A.; Kimberley, Mark; Liebhold, Andrew M.; Lowenstein, Frank L.; Marasas, Carissa; Nuding, Amelia; Olson, Lars; Speekmann, Christa; Springborn, Michael; Vieglais, Christina; Turner, James. 2011. Demonstrating the benefits of phytosanitary regulations: the case of ISPM 15.
• Aukema, Juliann E.; Leung, Brian; Kovacs, Kent; Chivers, Corey; Englin, Jeffrey; Frankel, Susan J.; Haight, Robert G.; Holmes, Thomas P.; Liebhold, Andrew M.; McCullough, Deborah G.; Von Holle, Betsy. 2011. Economic Impacts of Non-Native Forest Insects in the Continental United States.
• Koenig, Walter D.; Walters, Eric L.; Liebhold, Andrew M. 2011. Effects of gypsy moth outbreaks on North American woodpeckers.
• Mercader, Rodrigo J.; Siegert, Nathan W.; Liebhold, Andrew M.; McCullough, Deborah G. 2011. Influence of foraging behavior and host spatial distribution on the localized spread of the emerald ash borer, Agrilus planipennis.
• Mercader, Rodrigo J.; Siegert, Nathan W.; Liebhold, Andrew M.; McCullough, Deborah G. 2011. Simulating the effectiveness of three potential management options to slow the spread of emerald ash borer (Agrilus planipennis) populations in localized outlier sites.
• Morin, Randall S.; Oswalt, Sonja N.; Trotter, III , Robert T..; Liebhold, Andrew M. 2011. Status of Hemlock in the Eastern United States.
• Garnas, Jeffrey R.; Ayres, Matthew P.; Liebhold, Andrew M.; Evans, Celia. 2011. Subcontinental impacts of an invasive tree disease on forest structure and dynamics.
• Kovacs, Kent F.; Mercader, Rodrigo J.; Haight, Robert G.; Siegert, Nathan W.; McCullough, Deborah G.; Liebhold, Andrew M. 2011. The influence of satellite populations of emerald ash borer on projected economic damage in U.S. communities, 2010-2020.
• Holmes, Thomas P.; Liebhold, Andrew M.; Kovacs, Kent F.; Von Holle, Betsy. 2010. A spatial-dynamic value transfer model of economic losses from a biological invasion.
• Gilbert, Marius; Liebhold, Andrew. 2010. Comparing methods for measuring the rate of spread of invading populations.
• Kovacs, Kent F.; Haight, Robert G.; Liebhold, Andrew M.; McCullough, Deborah G.; Mercader, Rodrigo J.; Siegert, Nathan W. 2010. Cost of potential emerald ash borer damage in U.S.
• Kovacs, Kent F.; Haight, Robert G.; McCullough, Deborah G.; Mercader, Rodrigo J.; Siegert, Nathan W.; Liebhold, Andrew M. 2010. Cost of potential emerald ash borer damage in U.S communities, 2009-2019.
• Brockerhoff, Eckehard G.; Liebhold, Andrew M.; Richardson, Brian; Suckling, David M. 2010. Eradication of invasive forest insects: concepts, methods, costs and benefits.
• Liebhold, Andrew M.; Tobin, Patrick C. 2010. Exploiting the Achilles heels of pest invasions: allee effects, stratified dispersal and management of forest insect establishment and spread.
• Bjornstad, Ottar N.; Robinet, Christelle; Liebhold, Andrew M. 2010. Geographic variation in North American gypsy moth cycles: subharmonics, generalist predators, and spatial coupling.
• Aukema, J.E.; McCullough, D.G.; Holle, B.V.; Liebhold, A.M.; Frankel, S.J. 2010. Historical Accumulation of Nonindigenous Forest Pests in the Continental United States.
• Aukema, J.E.; McCullough, D.G.; Von Holle, B.; Liebhold, Andrew; Britton, Kerry; Frankel, S.J. 2010. Historical accumulation of nonindigenous forest pests in the Continental United States.
• Mercader, Rodrigo J.; Siegert, N.W.; Liebhold, A.M.; McCullough, D.G. 2009. A model for the spread of the emerald ash borer, Agrilus planipennis, in recently colonized sites..
• Morin, Randall S.; Liebhold, Andrew M.; Gottschalk, Kurt W. 2009. Anisotropic spread of hemlock woolly adelgid in the eastern United States.
• Mercader, Rodrigo J.; Siegert, Andrew M.; Liebhold, Andrew M.; McCullough, Deborah G. 2009. Dispersal of the emerald ash borer, Agrilus planipennis, in newly-colonized sites.
• Robinet, Christelle; Liebhold, Andrew M. 2009. Dispersal polymorphism in an invasive forest pest affects its ability to establish.
• Haight, Robert G.; Kovacs, Kent; Liebhold, Andrew M.; McCullough, Deborah G. 2009. Economic assessment of potential emerald ash borer damage in urban areas in the United States.
• Holmes, Thomas P.; Aukema, Juliann E.; Von Holle, Betsy; Liebhold, Andrew; Sills, Erin. 2009. Economic impacts of invasive species in forest past, present, and future.
• McManus, Michael L.; Liebhold, Andrew M. 2009. Gypsy moth IPM.
• Siegert, Nathan W.; Mercader, Rodrigo J.; McCullough, Deborah G.; Liebhold, Andrew M.; Poland, Therese M.; Heyd, Robert L. 2009. Manipulating spread and predicting dispersal of isolated emerald ash borer populations.
• Yamanaka, Takehiko; Liebhold, Andrew M. 2009. Mate-location failure, the Allee effect, and the establishment of invading populations.
• Siegert, Nathan W.; McCullough, Deborah G.; Liebhold, Andrew M.; Telewski, Frank W. 2009. Reconstruction of the establishment and spread of emerald ash borer through dendrochronological analysis.
• Haynes, Kyle J.; Liebhold, Andrew M.; Johnson, Derek M. 2009. Spatial analysis of harmonic oscillation of gypsy moth outbreak intensity.
• Plymale, Ruth C.; Liebhold, Andrew M.; Hajek, Ann E. 2009. Spatial population dynamics and heterogeneity of an insect/pathogen interaction.
• ​Haynes, Kyle J.; Liebhold, Andrew M.; Fearer, Todd M.; Wang, Guiming; Norman, Gary W.; Johnson, Derek M. 2009. Spatial synchrony propagates through a forest food web via consumer-resource interactions.
• Yamanaka, Takehiko; Liebhold, Andrew M. 2009. Spatially implicit approaches to understand the manipulation of mating success for insect invasion management.
• Kramer, Andrew M.; Dennis, Brian; Liebhold, Andrew M.; Drake, John M. 2009. The evidence for Allee effects.
• Tobin, Patrick C.; Robinet, Christelle; Johnson, Derek M.; Whitmire, Stefanie L.; Bjornstad, Ottar N.; Liebhold, Andrew M. 2009. The role of Allee effects in gypsy moth, Lymantria dispar (L.), invasions.
• Buntgen, Ulf; Frank, David; Liebhold, Andrew; Johnson, Derek; Carrer, Marco; Urbinati, Carlo; Grabner, Michael; Nicolussi, Kurt; Levanic, Tom; Esper, Jan. 2009. Three centuries of insect outbreaks across the European Alps.
• Tobin, Patrick C.; Whitmire, Stephanie L.; Johnson, Derek M.; Bjornstad, Ottar N.; Liebhold, Andrew M. 2008. Allee effects and gypsy moth invasions.
• Siegert, Nathan W.; McCullough, Deborah G.; Liebhold, Andrew M. 2008. Dendrochronological reconstruction of the establishment and spread of emerald ash borer.
• Liebhold, A.M.; Turcani, Marek; Kamata, Naoto. 2008. Inference of adult female dispersal from the distribution of gypsy moth egg masses in a Japanese city.
• Siegert, Nathan W.; Liebhold, Andrew M.; McCullough, Deborah G. 2008. Modeling the spatial and temporal dynamics of isolated emerald ash borer populations.
• Liebhold, Andrew M.; Tobin, Patrick C. 2008. Population ecology of insect invasions and their management.
• Bjørnstad, Ottar N.; Liebhold, Andrew M.; Johnson, Derek M. 2008. Transient synchronization following invasion: revisiting Moran's model and a case study.
• Bogich, Tiffany L.; Liebhold, Andrew; Shea, Katriona. 2007. A model for the optimization of the detection and eradication of isolated gypsy moth colonies.
• Tobin, Patrick C.; Liebhold, Andrew M.; Roberts, E. Anderson. 2007. Comparison of methods for estimating the spread of a non-indigenous species.
• Tobin, Patrick C.; Whitmire, Stephanie L.; Johnson, Derek M.; Bjornstad, Ottar N.; Liebhold, Andrew M. 2007. Invasion speed is affected by geographical variation in the strength of Allee effects.
• Siegert, Nathan W.; McCullough, Deborah G.; Liebhold, Andrew M.; Telewski, Frank W. 2007. Reconstructing the temporal and spatial dynamics of emerald ash borer adults through dendrochronological analyses.
• Siegert, Nathan W.; McCullough, Deborah G.; Liebhold, Andrew M.; Telewski, Frank W. 2007. Resurrected from the ashes: a historical reconstruction of emerald ash borer dynamics through dendrochronological analysis.
• Morin, Randall S.; Liebhold, Andrew M.; Tobin, Patrick C.; Gottschalk, Kurt W.; Luzader, Eugene. 2007. Spread of beech bark disease in the eastern United States and its relationship to regional forest composition.
• Robinet, Christelle; Liebhold, Andrew; Gray, David. 2007. Variation in developmental time affects mating success and Allee effects.
• Lance, D. R.; Liebhold, A.; Mastro, V. C. 2007. Weather, distance, synchrony and mate-finding success in Lymantria dispar.
• Liebhold, Andrew M.; Work, Timothy T.; McCullough, Deborah G.; Cavey, Joseph F.; Cavey, Joseph F. 2006. Airline Baggage as a Pathway for Alien Insect Species Invading the United States.
• Johnson, Derk M.; Liebhold, Andrew M.; Tobin, Patrick C.; Bjornstad, Ottar N. 2006. Allee effects and pulsed invasion by the gypsy moth.
• Morin, Randall S.; Liebhold, Andrew M; Gottschalk, K.W.; Woodall, Chris W.; Twardus, Daniel B.; White, Robert L.; Horsley, Stephen B.; Ristau, Todd E. 2006. Analysis of forest health monitoring surveys on the Allegheny National Forest (1998-2001).
• Liebhold, Andrew M.; Johnson, Derek M.; Bjørnstad, Ottar N. 2006. Geographic variation in density-dependent dynamics impacts the synchronizing effect of dispersal and regional stochasticity.
• Johnson, Derek M.; Liebhold, Andrew M.; Bjørnstad, Ottar N. 2006. Geographical variation in the periodicity of gypsy moth outbreaks.
• Liebhold, Andrew M.; Tobin, Patrick C. 2006. Growth of newly established alien populations: comparison of North American gypsy moth colonies with invasion theory.
• McCullough, Deborah G.; Work, Timothy T.; Cavey, Joseph F.; Liebhold, Andrew M.; Marshall, David. 2006. Interceptions of nonindigenous plant pests at US ports of entry and border crossings over a 17-year period.
• Brockerhoff, Eckehard G.; Liebhold, Andrew M.; Jactel, Hervé. 2006. The ecology of forest insect invasions and advances in their management.
• Komura, Ryotaro; Liebhold, Andrew; Esaki, Koujiro; Muramoto, Ken-ichiro; Kamata, Naoto. 2005. Analysis of Japanese Oak Wilt Spread Using Aerial Photography and GIS.
• Okland, Bjorn; Liebhold, Andrew M.; Bjornstad, Ottar N.; Erbilgin, Nadir; Krokene, Paal; Krokene, Paal. 2005. Are bark beetle outbreaks less synchronous than forest Lepidoptera outbreaks.
• Johnson, Derek M.; Liebhold, Andrew M.; Bjornstad, Ottar N.; Mcmanus, Michael L.; Mcmanus, Michael L. 2005. Circumpolar variation in periodicity and synchrony among gypsy moth populations.
• Koenig, Walter D.; Liebhold, Andrew M.; Liebhold, Andrew M. 2005. Effects of periodical cicada emergences on abundance and synchrony of avian populations.
• Liebhold, A.M.; Raffa, K.F.; Diss, A.L.; Diss, A.L. 2005. Forest type affects predation on gypsy moth pupae.
• Morin, Randall S.; Liebhold, Andrew M.; Luzader, Eugene R.; Lister, Andrew J.; Gottschalk, Kurt W.; Twardus, Daniel B. 2005. Mapping host-species abundance of three major exotic forest pests.
• Siegert, Nathan W.; McCullough, Deborah G.; Liebhold, Andrew M.; Telewski, Frank W. 2005. Reconstructing the temporal and spatial dynamics of emerald ash borer in black ash: a case study of an outlier site in Roscommon County, Michigan.
• Liebhold, Andrew; Morin, Randall; Gottschalk, Kurt; Twardus, Dan; Twardus, Dan. 2005. The Biogeography of Beech Bark Disease Invasion of North America.
• Evans, Celia; Ayres, Matthew; Twery, Mark; Houston, David R.; Liebhold, Andrew; Liebhold, Andrew. 2005. Using Models to Identify Forests at Risk of Major Structure and Compositional Change due to Beech Bark Disease.
• Morin, Randall S.; Liebhold, Andrew M.; Gottschalk, Kurt W. 2004. Area-Wide Analysis of Hardwood Defoliator Effects on Tree Conditions in the Allegheny Plateau.
• Liebhold, Andrew M.; Gottschalk, Kurt W.; Guldin, James M.; Muzika, Rose-Marie. 2004. Gypsy Moth Defoliation Potential in the Ouachita/Ozark Highlands Region.
• Raimondo, Sandy; Turcáni, Marek; Patoèka, Jan; Liebhold, Andrew M. 2004. Interspecific synchrony among foliage-feeding forest Lepidoptera species and the potential role of generalist predators as synchronizing agents.
• Tobin, Patrick C.; Sharov, Alexei A.; Liebhold, Andrew A.; Leonard, Donna S.; Roberts, E. Anderson; Learn, Matthew R. 2004. Management of the gypsy moth through a decision algorithm under the STS project.
• Muzika, R.M.; Grushecky, S.T.; Liebhold, A.M.; Smith, R.L. 2004. Using thinning as a management tool for gypsy moth: the influence on small mammal abundance.
• Liebhold, Andrew M.; Sork, Victoria; Peltonen, Mikko; Koenig, Walter; Bjørnstad, Ottar N.; Westfall, Robert; Elkinton, Joseph; Knops, Johannes M. H. 2004. Within-population spatial synchrony in mast seeding of North American oaks.
• Liebhold, Andrew M. 2003. Alien species, agents of global change: ecology and management of the gypsy moth in North America as a case history.
• Liebhold, Andrew M.; Morin, Randall S.; Lister, Andrew; Gottschalk, Kurt W.; Luzader, Eugene; Twardus, Daniel. 2003. Mapping forest risk associated with beech bark disease.
• Liebhold, Andrew M.; Morin, Randall S.; Lister, Andrew; Gottschalk, Kurt W.; Luzader, Eugene; Twardus, Daniel. 2003. Mapping forest risk associated with the gypsy moth.
• Liebhold, Andrew M.; Morin, Randall S.; Lister, Andrew; Gottschalk, Kurt W.; Luzader, Eugene; Twardus, Daniel. 2003. Mapping forest risk associated with the hemlock woolly adelgid.
• Gottschalk, Kurt W.; Morin, Randall S.; Liebhold, Andrew M. 2003. Potential susceptibility of eastern forests to sudden oak death, Phytophthora ramorum.
• Turcani, Marek; Liebhold, Andrew; McManus, Michael; Novotny, Julius. 2003. Preliminary results on predation of gypsy moth egg masses in Slovakia.
• Turcani, Marek; Liebhold, Andrew M.; McManus, Michael; Novotný, Július. 2003. Preliminary results on predation of gypsy moth pupae during a period of latency in Slovakia.
• McManus, Michael L.; Liebhold, Andrew M.; [eds.], . 2003. Proceedings: Ecology, Survey and Management of Forest Insects.
• Liebhold, Andrew; Bascompte, Jordi; Bascompte, Jordi. 2003. The Allee effect, stochastic dynamics and the eradication of alien species.
• Sharov, Alexei A.; Leonard, Donna; Liebhold, Andrew M.; Roberts, E. Anderson; Dickerson, Willard; Dickerson, Willard. 2002. "Slow the spread" a national program to contain the gypsy moth.
• Williams, David W.; Liebhold, Andrew M. 2002. Climate change and the outbreak ranges of two North American bark beetles.
• Liebhold, A. M.; Gurevitch, J. 2002. Integrating the statistical analysis of spatial data in ecology.
• Morin, R.S.; Liebhold, A.M.; Gottschalk, K.W.; Twardus, D.B.; Acciavatti, R.E.; White, R.L.; Horsley, S.B.; Smith, W.D.; Luzader, E.R. 2001. Forest health conditions on the Allegheny National Forest (1989-1999): Analysis of forest health monitoring surveys.
• Liebhold, A.M.; McManus, M.L.; Otvos, I.S.; Fosbroke, S.L.C. 2001. Proceedings: integrated management and dynamics of forest defoliating insects.
• ​Muzika, R.M.; Liebhold, A.M. 2000. A critique of silvicultural approaches to managing defoliating insects in North America.
• Williams, David W.; Long, Robert P.; Wargo, Philip M.; Liebhold, Andrew M. 2000. Effects of climate change on forest insect and disease outbreaks.
• Liebhold, Andrew. 2000. Population processes during establishment and spread of invading species: implications for survey and detection programs.
• Liebhold, Andrew M.; Muzika, Rose-Marie; Gottschalk, Kurt W. 1998. Does thinning affect gypsy moth dynamics.
• Muzika, R.M.; Liebhold, A.M.; Gottschalk, K.W. 1998. Effects of management on gypsy moth dynamics and impact: an eight-year study.
• McManus, M.L.; Liebhold, A.M., eds. 1998. Proceedings: population dynamics, impacts, and integrated management of forest defoliating insects.
• Liebhold, Andrew M.; Gottschalk, Kurt W.; Mason, Douglas A.; Bush, Renate R. 1997. Forest susceptibility to the gypsy moth.
• Liebhold, Andrew M.; Gottschalk, Kurt W.; Luzader, Eugene R.; Bush, Renate; Twardus, Daniel B. 1997. Gypsy moth in the United States: an atlas.
• Gregoire, J.C.; Liebhold, A.M.; Stephen, F.M.; Day, K.R.; Salom, S.M. 1997. Proceedings: Integrating cultural tactics into the management of bark beetle and reforestation pests.
• Muzika, Rose-Marie; Liebhold, Andrew; Gottschalk, Kurt. 1997. Silvicultural methods of Lymantria dispar L. management: effects on Agrilus bilineatus (Weber) populations.
• Williams, David W.; Liebhold, Andrew M. 1996. Herbivorous insects and climate change: potential changes in the spatial distribution of forest defoliator outbreaks.
• ​Williams, David W.; Liebhold, Andrew M. 1995. Forest defoliators and climatic change: potential changes in spatial distribution of outbreaks of western spruce budworm (Lepidoptera: Tortricidae) and gypsy moth (Lepidoptera Lymantriidae).
• Liebhold, Andrew M.; Gottschalk, Kurt W.; Muzika, Rose-Marie; Montgomery, Michael E.; Young, Regis; O'Day, Kathleen; Kelley, Brooks. 1995. Suitability of North American tree species to gypsy moth: a summary of field and laboratory tests..
• Liebhold, Andrew M.; Barrett, Hope R., eds. 1993. Proceedings: Spatial analysis and forest pest management.
• Liebhold, Andrew; Elkinton, Joseph S. 1991. Analysis of spatial density dependence in gypsy moth mortality.
• Elkinton, Joseph S.; Smith, Harvey R.; Liebhold, Andrew M. 1991. Impact of small mammal predators on gypsy moth.
• Liebhold, Andrew; Halverson, Joel; Elmes, Gregory; Hutchinson, Jay. 1991. Landscape ecology of gypsy moth in the Northeastern United States.
• Russo, Joseph M.; Kelley, John G. W.; Liebhold, Andrew M. 1991. Mesoscale landscape model of gypsy moth phenology.

Research Highlights

Highlight	Title	Year
NRS-2016-164	Comparison of Native and Non-native Insect Communities Reflects Importance of Pathways Insect species are accidentally moved around the world and often cause considerable damage when established. An analysis of insect invasions wor ...	2016
NRS-2017-29	Predicting pest invasions During the last 150 years, hundreds of forest insects have been accidently introduced to the U.S., and many of these have caused substantial dam ...	2017