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Justin B. Runyon

Justin Runyon

Research Entomologist

Montana State University Campus
1648 South 7th Avenue
Bozeman, MT 59717-2780
Contact Justin B. Runyon

Current Research

Justin's research focuses on plant-insect chemical ecology. His current research includes: (1) understanding the role floral scent plays in plant-pollinator interactions and how environmental stressors alter scent and pollinator attraction, (2) examining tree chemistry to understand host selection and resistance to bark beetles, and (3) exploring chemically-mediated interactions between invasive plants and herbivores.

Justin also has projects on assessing “pollinator-friendliness” of native plants for restoration, determining management and disturbance effects (e.g., bark beetle outbreaks) on pollinators, and the taxonomy and biodiversity of long-legged flies (Diptera: Dolichopodidae).

Research Interests

Chemistry plays a critical role in most species interactions and underpins community structure and function. I seek to understand chemistry's function in the World and exploit it to better manage and restore ecosystems. One example is the chemical interactions between bark beetles and trees. Our work revealed that host-searching mountain pine beetles are repelled by volatiles emitted by Great Basin Bristlecone pine (but strongly attracted to odors from other pine species). Understanding what it is about this blend of odors that repels beetles could allow development of new strategies for managing this important forest insect. Another example is biological control, the only tool capable of managing widespread exotic plant invasions. However, some biological control agents obtain approval and are released, but fail to impact weed populations. A better understanding of the interactions between biocontrol agents and their invasive host plants is needed to identify the factors which promote or limit successful biocontrol. My approach is to apply the chemical ecology of plant-herbivore interactions to classical biological control of weeds - two fields which have largely progressed independently to date. Chemistry plays a central role in determining ecological outcomes between plants and insects and should provide information that can be used to better predict which potential agents are most likely to be effective.

Past Research

1. Chemical Ecology of interactions between parasitic plants, their host plants, and insect herbivores. 2. Biological control and chemical ecology of the tritrophic system consisting of the wheat stem sawfly, host plants, and natural enemies. 3. How bark beetle attack alters tree chemistry and how this affects flammability to better predict and manage wildfires. 4. exploiting sagebrush chemistry to improve restoration.

Why This Research is Important

This research will better position us to devise and apply management to address important issues including invasive plants, pollinators, and bark beetles. It will also advance our basic understanding of the ecology of plant-insect interactions.


  • University of Virginia's College at Wise, VA, B.S., Biology and Mathematics, 1998
  • Montana State University, Bozeman, MT, M.S., Entomology, 2001
  • Pennsylvania State University, University Park, PA, Ph.D., Entomology, 2008
  • Awards

    Penn State College of Agricultural Sciences Outstanding Recent Alumnus Award, 2014
    This is "the highest honor that the College of Agricultural Sciences and the Ag Alumni Society present to select alumni who have achieved notable professional achievements and brought distinction to themselves, the college, and the University."
    Kavli Fellow, 2014
    Invited to participate in the Kavli Frontiers of Science symposiumin Medan, Indonesia in June 2014. This is the premiere activity within the U.S. National Academy of Sciences for distinguished young scientists.
    Deputy Chief's Early Career Scientist Award, 2012
    This honor was awarded "in recognition of your outstanding research productivity and your impacts on science including your major efforts in science delivery." Received February 2013 in Washington D.C.
    Presidential Early Career Award for Science and Engineering (PECASE), 2012
    This is "the highest honor bestowed by the United States Government on science and engineering professionals in the early stages of their independent research careers". Received April 2014 in Washington D.C.

    Featured Publications


    Glenny, Will; Runyon, Justin B.; Burkle, Laura A. , 2022. A review of management actions on insect pollinators on public lands in the United States
    Fettig, Christopher J.; Munson, A. Steven; Runyon, Justin B.; Mortenson, Leif A.; Steed, Brytten E.; Gibson, Kenneth E.; Jørgensen, Carl L.; McKelvey, Stephen R.; McMillin, Joel D.; Audley, Jackson P.; Negrón, Jose F. , 2022. Ecological consequences of mountain pine beetle outbreaks in the Intermountain West
    Fettig, Chris; Hood, Sharon M.; Runyon, Justin B.; Stalling, Christine M. , 2021. Bark beetle and fire interactions in western coniferous forests: Research findings
    Bentz, Barbara J.; Soderberg, David; Runyon, Justin B.; Hood, Sharon M.; Vandygriff, James C.; Hansen, Matt; Stephens, Sky , 2021. Chapter 10 - Vulnerability of Rocky Mountain bristlecone pine to mountain pine beetle
    Audley, Jackson P.; Fettig, Christopher J.; Steven Munson, A.; Runyon, Justin B.; Mortenson, Leif A.; Steed, Brytten E.; Gibson, Kenneth E.; Jørgensen, Carl L.; McKelvey, Stephen R.; McMillin, Joel D.; Negrón, Jose F. , 2021. Dynamics of beetle-killed snags following mountain pine beetle outbreaks in lodgepole pine forests
    Finch, Deborah M.; Butler, Jack L.; Runyon, Justin B.; Fettig, Christopher J.; Kilkenny, Francis F.; Jose, Shibu; Frankel, Susan J.; Cushman, Samuel A.; Cobb, Richard C.; Dukes, Jeffrey S.; Hicke, Jeffrey A.; Amelon, Sybill K. , 2021. Effects of Climate Change on Invasive Species
    Runyon, Justin B. , 2021. Invasive Species Science Update (No. 13)
    Poland, Therese M.; Juzwik, Jennifer; Rowley, Allen; Huebner, Cynthia D.; Kilgo, John C.; Lopez, Vanessa M.; Olson, Deanna H.; Pearson, Dean E.; Progar, Robert; Rabaglia, Robert; Rothlisberger, John D.; Runyon, Justin B.; Sing, Sharlene E. , 2021. Management of Landscapes for Established Invasive Species
    Gaskin, John F.; Espeland, Erin; Johnson, Casey D.; Larson, Diane L.; Mangold, Jane M.; McGee, Rachel A.; Milner, Chuck; Paudel, Shishir; Pearson, Dean E.; Perkins, Lora B.; Prosser, Chadley W.; Runyon, Justin B.; Sing, Sharlene E.; Sylvain, Zachary A.; Symstad, Amy J.; Tekiela, Daniel R. , 2021. Managing invasive plants on Great Plains grasslands: A discussion of current challenges
    Foote, Gabriel; Runyon, Justin B.; Fettig, Christopher; Foote, Nathaniel; Ross, Darrell W. , 2021. Wild bee response to application of the Douglas-fir beetle anti-aggregation pheromone, 3-methylcyclohex-2-en-1-one
    Foote, Gabriel; Fettig, Christopher; Ross, Darrell; Runyon, Justin B.; Coleman, Tom; Gaylord, Monica; Graves, Andrew; McMillin, Joel; Mortenson, Leif; Mafra-Neto, Agenor , 2020. A biodegradable formulation of MCH (3-methylcyclohex-2-en-1-one) for protecting Pseudotsuga menziesii from Dendroctonus pseudotsugae (Coleoptera: Curculionidae) colonization
    Foote, Gabriel; Foote, Nathaniel; Runyon, Justin B.; Ross, Darrell; Fettig, Christopher J. , 2020. Changes in the summer wild bee community following a bark beetle outbreak in a Douglas-fir forest
    Runyon, Justin B.; Fettig, Christopher J.; Trilling, Jared; Munson, A. Steven; Mortenson, Leif A.; Steed, Brytten E.; Gibson, Kenneth E.; Jørgensen, Carl L.; McKelvey, Stephen R.; McMillin, Joel D.; Audley, Jackson P.; Negron, Jose , 2020. Changes in understory vegetation including invasive weeds following mountain pine beetle outbreaks
    Malone, Shealyn C.; Weaver, David K.; Seipel, Tim F.; Menalled, Fabian D.; Hofland, Megan L.; Runyon, Justin B.; Trowbridge, Amy M. , 2020. Herbivore-induced volatile emissions are altered by soil legacy effects in cereal cropping systems
    Audley, Jackson P.; Fettig, Christopher J.; Steven Munson, A.; Runyon, Justin B.; Mortenson, Leif A.; Steed, Brytten E.; Gibson, Kenneth E.; Jørgensen, Carl L.; McKelvey, Stephen R.; McMillin, Joel D.; Negron, Jose , 2020. Impacts of mountain pine beetle outbreaks on lodgepole pine forests in the Intermountain West, U.S., 2004–2019
    Burkle, Laura A.; Glenny, William R.; Runyon, Justin B. , 2020. Intraspecific and interspecific variation in floral volatiles over time
    Runyon, Justin B. , 2020. Invasive Species Science Update (No. 12)
    Ott, Daniel S.; Fettig, Christopher J.; Munson, A. Steven; Runyon, Justin B.; Ross, Darrell W. , 2020. Physical and chemical characteristics of blue and Engelmann spruce relative to spruce beetle host selection and colonization
    Gray, Curtis A.; Runyon, Justin B.; Jenkins, Michael J. , 2019. Great Basin bristlecone pine volatiles as a climate change signal across environmental gradients
    Runyon, Justin B. , 2019. Invasive Species Science Update (No. 11)
    Brown, Brian V.; Borkent, Art; Adler, Peter H.; Amorim, Dalton de Souza; Barber, Kevin; Bickel, Daniel; Boucher, Stephanie; Brooks, Scott E.; Burger, John; Burington, Zelia L.; Capellari, Renato S.; Costa, Daniel N. R.; Cumming, Jeffrey M.; Curler, Greg; Dick, Carl W.; Epler, John H.; Fisher, Eric; Gaimari, Stephen D.; Gelhaus, Jon; Grimaldi, David A.; Hash, John; Hauser, Martin; Hippa, Heikki; Ibanez-Bernal, Sergio; Jaschhof, Mathias; Kameneva, Elena P.; Kerr, Peter H.; Korneyev, Valery; Korytkowski, Cheslavo A.; Kung, Giar-Ann; Kvifte, Gunnar Mikalsen; Lonsdale, Owen; Marshall, Stephen A.; Mathis, Wayne; Michelsen, Verner; Naglis, Stefan; Norrbom, Allen L.; Paiero, Steven; Pape, Thomas; Pereira-Colavite, Alessandre; Pollet, Marc; Rochefort, Sabrina; Rung, Alessandra; Runyon, Justin B.; Savage, Jade; Silva, Vera C.; Sinclair, Bradley J.; Skevington, Jeffrey H.; Stireman, John O. III; Swann, John; Thompson, F. Christian; Vilkamaa, Pekka; Wheeler, Terry; Whitworth, Terry; Wong, Maria; Wood, D. Monty; Woodley, Norman; Yau, Tiffany; Zavortink, Thomas J.; Zumbado, Manuel A. , 2018. Comprehensive inventory of true flies (Diptera) at a tropical site
    Runyon, Justin B. , 2018. Invasive Species Science Update (No. 10)
    Runyon, Justin B. , 2017. Invasive Species Science Update (No. 9)
    Rand, Tatyana A.; Morrill, Wendell L.; Runyon, Justin B.; Hoelmer, Kim A.; Shanower, Thomas G.; Littlefield, Jeffrey L.; Weaver, David K. , 2016. Assessing phenological synchrony between the Chinese sawfly, Cephus fumipennis, its egg-larval parasitoid, Collyria catoptron, and the North American sawfly, Cephus cinctus: Implications for biological control
    Finch, Deborah M.; Pendleton, Rosemary L.; Reeves, Matt C.; Ott, Jeffrey E.; Kilkenny, Francis F.; Butler, Jack L.; Ott, Jacqueline P.; Pinto, Jeremiah R.; Ford, Paulette L.; Runyon, Justin B.; Rumble, Mark A.; Kitchen, Stanley G. , 2016. Rangeland drought: Effects, restoration, and adaptation [Chap. 8]
    Pape, Thomas; Allison, Allen; Bickel, Daniel J.; Dikow, Torsten; Donegan, Thomas; Duszynski, Donald W.; El-Hawagry, Magdi S.; Evenhuis, Neal L.; Fautin, Daphne G.; Gaimari, Stephen D.; Gharali, Babak; Greenwalt, Dale E.; Kaiser, Hinrich; Kirk-Spriggs, Ashley H.; Lamas, Gerardo; Lonsdale, Owen; Mah, Christopher; Marshall, Stephen A.; Meier, Rudolf; Ohl, Michael; Patterson, David J.; Penev, Lyubomir; Pentcheff, N. Dean; Pyle, Richard L.; Rubinoff, Daniel J.; Runyon, Justin B.; Tallowin, Oliver; Thorpe, Stephen; Nanjing, Bo Wang; Welter-Schultes, Francisco; Yanega, Douglas; Yang, Ding; Hangzhou, Gang Yao; Yeung, Norine W. , 2016. Species can be named from photos
    Dumroese, Kasten; Luna, Tara; Richardson, Bryce A.; Kilkenny, Francis F.; Runyon, Justin B. , 2015. Conserving and restoring habitat for Greater Sage-Grouse and other sagebrush-obligate wildlife: The crucial link of forbs and sagebrush diversity
    Fettig, Christopher J.; Gibson, Kenneth E.; Jørgensen, Carl L.; Munson, Steven; Negrón, Jose F.; Runyon, Justin B.;  Steed, Brytten E. , 2015. Impacts of mountain pine beetle (Dendroctonus ponderosae) outbreaks on forest conditions in the Intermountain West
    Gray, Curtis A.; Runyon, Justin B.; Jenkins, Michael J.; Giunta, Andrew D. , 2015. Mountain pine beetles use volatile cues to locate host limber pine and avoid non-host Great Basin bristlecone pine
    Page, Wesley G.; Jenkins, Michael J.; Runyon, Justin B. , 2014. Spruce beetle-induced changes to Engelmann spruce foliage flammability
    Gillette, Nancy E.; Wood, David L.; Hines, Sarah J.; Runyon, Justin B.; Negron, Jose , 2014. The once and future forest: Consequences of mountain pine beetle treatment decisions
    Littlefield, J. L.; Markin, G.; Kashefi, J.; de Meij, A.; Runyon, Justin B. , 2013. The release and recovery of Bradyrrhoa gilveolella on rush skeletonweed in southern Idaho
    Runyon, Justin B.; Butler, Jack L.; Friggens, Megan M.; Meyer, Susan E.; Sing, Sharlene E. , 2012. Invasive species and climate change (Chapter 7)
    Page, Wesley G.; Jenkins, Michael J.; Runyon, Justin B. , 2012. Mountain pine beetle attack alters the chemistry and flammability of lodgepole pine foliage
    Runyon, Justin B.; Robinson, Harold , 2010. Hurleyella, a new genus of Nearctic Dolichopodidae (Diptera)
    Runyon, Justin B.; Mescher, Mark C.; Felton, Gary W.; De Moraes, Consuelo M. , 2010. Parasitism by Cuscuta pentagona sequentially induces JA and SA defence pathways in tomato
    Runyon, Justin B.; Mescher, Mark C.; De Moraes, Consuelo M. , 2010. Plant defenses against parasitic plants show similarities to those induced by herbivores and pathogens
    Weaver, David K.; Buteler, Micaela; Hofland, Megan L.; Runyon, Justin B.; Nansen, Christian; Talbert, Luther E.; Lamb, Peggy; Carlson, Gregg R. , 2009. Cultivar preferences of ovipositing wheat stem sawflies as influenced by the amount of volatile attractant
    Runyon, Justin B.; Tooker, John F.; Mescher, Mark C.; De Moraes, Consuelo M. , 2009. Parasitic plants in agriculture: Chemical ecology of germination and host-plant location as targets for sustainable control: A review
    Runyon, Justin B.; Mescher, Mark C.; De Moraes, Consuelo M. , 2008. Parasitism by Cuscuta pentagona attenuates host plant defenses against insect herbivores
    Runyon, Justin B. , 2008. Richard L. Hurley, 1934-2008
    Mescher, Mark C.; Runyon, Justin B.; De Moraes, Consuelo M. , 2006. Plant host finding by parasitic plants: A new perspective on plant to plant communication
    Weaver, David K.; Nansen, Christian; Runyon, Justin B.; Sing, Sharlene E.; Morrill, Wendell L. , 2005. Spatial distributions of Cephus cinctus Norton (Hymenoptera: Cephidae) and its braconid parasitoids in Montana wheat fields
    Nansen, Christian; Weaver, David K.; Sing, Sharlene E.; Runyon, Justin B.; Morrill, Wendell L.; Grieshop, Matthew J.; Shannon, Courtney L.; Johnson, Megan L. , 2005. Within-field spatial distribution of Cephus cinctus (Hymenoptera: Cephidae) larvae in Montana wheat fields
    Daisy, Bryn H.; Strobel, Gary A.; Castillo, Uvidelio; Ezra, David; Sears, Joe; Weaver, David K.; Runyon, Justin B. , 2002. Naphthalene, an insect repellent, is produced by Muscodor vitigenus, a novel endophytic fungus
    A bright green native sweat bee (Agapostemon) on a flower
    There is an urgent and growing need to restore habitat for pollinators, especially bees. Increasing floral resources by revegetating with native flowering plants is an effective way to benefit pollinators. We assessed the pollinator-friendliness of flowering plant species available for restoration in Region One and provide score cards to allow managers to select and tailor mixes that are most beneficial to bees. 
    Lodgepole pine trees recently killed by mountain pine beetles.
    Bark beetle outbreaks alter forests in many ways, but the effects outbreaks have on understory vegetation are poorly understood despite the importance for overstory succession, nutrient cycling, water quality, soil erosion, and wildlife. Beetle outbreaks can also change forests in ways that could promote invasion by nonnative weeds, but this is rarely studied. Forest Service scientists assessed changes in understory vegetation and invasive weeds in lodgepole pine forests in the Northern Rockies following recent mountain pine beetle outbreaks.
    An ancient Great Basin bristlecone pine in the White Mountains, California.
    Pine trees emit characteristic and strong odors from their foliage. While aesthetically pleasing to humans, these volatile organic compounds serve many functions, including defense against insects and pathogens. We compared the odors from foliage of eight species of high-elevation five-needle pines in Europe and North America that vary in resistance to the mountain pine beetle and white pine blister rust and identified the most important compounds for classifying resistant and susceptible species.
    Collecting floral scent of blanketflower (Gaillardia aristata), one of 47 plant species sampled in the community
    In diverse communities, bees visit flowers of plants, forming complex webs of interactions. The structure of these webs can tell us about how communities function and guide their conservation and restoration, yet we know little about the cues that regulate these webs. We analyzed floral scent of 47 plant species and bee visitors across the growing season in a meadow community and found that floral scent is a key cue structuring bee-forb interactions. 
    Collecting sagebrush volatiles (odors) in a common garden near Ephraim, Utah.
    Big sagebrush (Artemisia tridentata) is the dominant plant species across much of the Western U.S. and provide critical habitat and food for many endemic species, including the threatened greater sage-grouse. Sagebrush habitat is imperiled due to disturbances and increased wildfire frequency due to exotic annual grasses. Identification of big sagebrush subspecies is difficult, but critical for successful restoration. Researchers discover that volatiles emitted by sagebrush species and subspecies differ in consistent ways and can be used to accurately identify plants.
    Herbicide treatment targeting the invasive plant, spotted knapweed, in Montana.
    A rapidly emerging problem is that of secondary invasion – an increase in non-target exotics following efforts to suppress targeted invasive plants. Researchers conducted a global literature review and meta-analysis directed at quantifying the magnitude of secondary invasion effects and identifying possible causes in order to improve management outcomes. 
    Common tansy (USFS photo)
    Resource managers are using burning and thinning treatments more and more in western forests to manage the infestation of insects and disease as well as to reduce wildfire hazards. Unfortunately, these treatments can trigger the invasion and spread of invasive plants, which can thwart restoration efforts. A recently published, long-term Forest Service study conducted at the Tenderfoot Creek Experimental Forest (TCEF) in Montana helps shed some light on the spread of invasive plants.
    Pollinators assist 80 percent of flowering plants in their reproduction, which accounts for much of the food ingested by humans and wildlife. The worldwide decline in pollinators highlights the importance of understanding factors affecting plant-pollinator interactions. We examined how drought, which is predicted to increase in the Western United States due to climate change, affected floral odors and pollinator attraction in four plant species in Montana.
    There is currently no pollinator restoration synthesis specific to wildlands or public lands. This project will review restoration of pollinators on public lands in the United States, including what has worked and what hasn’t, and identify future needs and directions.
    This project will conduct a science-based assessment of the pollinator-friendliness of plant species available for restoration and rehabilitation projects in Region 1.  A guide will be developed for several habitat types to tailor and recommend seed mixes that support the greatest number of species and abundance of pollinators.
    Invasive plants and their negative effects on biodiversity and landscapes are one of the greatest threats to ecosystems. The importance of plant chemistry in successful biocontrol is becoming evident, and the emerging science on plant-insect chemical ecology should provide valuable information regarding what types of insects are most likely to impact weed populations - saving time and money and maximizing the success of this powerful management tool.
    This research seeks to collect, identify, describe, and classify species of long-legged flies (Dolichopodidae), an important and diverse group of insects. 
    Rocky Mountain Research Station scientists and collaborators are working to determine how bark beetle attacks change the moisture and chemistry of several tree species and how these changes affect flammability. Findings will allow us to improve fire behavior and risk models to better predict and manage wildfires and protect property and human life.