You are here

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) exploring chemically-mediated ecological interactions between invasive plants and herbivores to improve biocontrol as a management tool, (2) examining how bark beetle attack alters tree chemistry and how this affects flammability to better predict and manage wildfires, (3) investigating the roles plant volatiles play in plant-pollinator interactions and how climate change alters these interactions at the community level, and (4) exploiting sagebrush chemistry to improve restoration.

Justin also researches 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 biological control, the only tool capable of managing widespread exotic plant invasions, which, at its most successful, can offer long-term solutions to weed problems. However, some biological control agents obtain approval and are released, but fail to impact weed populations. This is troublesome because exploration, testing, and approval for each agent take many years and is estimated to cost several millions of dollars to complete. Moreover, ineffective agents can cause unwanted ecological changes in the communities in which they occur. 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 invasive 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. Taxonomy and revisionary studies of long-legged flies (Diptera: Dolichopodidae).

Why This Research is Important

Invasive species present one of the greatest threats to the health and sustainability of ecosystems worldwide. This research will better position us to devise and apply biological control to address plant invasions. It will also advance our basic understanding of the ecology of plant-insect interactions and the conditions under which herbivory translates into meaningful changes in plant populations - fundamental ecological questions that hold great promise for managing invasive plants.


  • 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


    Finch, Deborah M.; Pendleton, Rosemary L.; Reeves, Matt C.; Ott, Jeffrey E.; Kilkenny, Francis; 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]
    Pearson, Dean E.; Ortega, Yvette K.; Runyon, Justin B.; Butler, Jack L., 2016. Secondary invasion: The bane of weed management
    Dumroese, Kasten; Luna, Tara; Richardson, Bryce A.; Kilkenny, Francis; 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
    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.; 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.; 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
    Collecting sagebrush volatiles (odors) in a common garden near Ephraim, Utah.
    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)
    A long-term study of thinning and burning treatments in Montana found that most invasive weeds coming in behind the treatment were confined to roadways.
    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.