UC Davis Seminars: Two USDA Forest Entomologists to Zero in on Bark Beetles

There's so much to know about bark beetles! How can a tiny insect wreak such havoc in our forests?

Two USDA forest entomologists will be presenting in-person and virtual seminars at the University of California, Davis on Tuesday, Jan. 31 and Wednesday, Feb. 1. If you're around UC Davis, drop in and hear the seminars,  sponsored by the UC Davis Department of Entomology and Nematology. They'll take place at 4:10 p.m. in 122 Briggs Hallon Kleiber Hall Drive, located near the UC Davis police and fire departments.

Or, you can access the seminars on Zoom.

The first speaker is Justin Runyon, who will deliver his seminar at 4:10 p.m., Tuesday, Jan. 21 on "Secrets of a Long Life: Chemical Defense of Bark Beetles by Bristlecone Pines." The Zoom link: 

Next is Chris Fettig, who will speak at 4:10 p.m., Wednesday, Feb. 1 on "Bark Beetles: How Tiny Insects Are Transforming Western Forests with a Little Help From Climate Change." The Zoom link:

Host for both seminars is UC Davis doctoral student Crystal Homicz, who is advised by Fettig. She began her studies with forest entomologist and chemical ecologist Steve Seybold (1959-2019). Her dissertation research focuses on western pine beetle and red turpentine beetle interactions with forest disturbances, such as drought, wildfire and prescribed fire. 

Justin Runyon

"Bristlecone pines are iconic species that can live to be thousands of years old," Runyon says in his abstract. "Secrets to their great longevity include a stable environment, sectored architecture, and avoidance of fire. However, to survive thousands of years, these trees must also avoid getting attacked by tree-killing bark beetles."

"Only in the last few years have we begun to uncover how bristlecone pines do this," he related. "We use field work, chemical ecology and laboratory assays to understand interactions between long-lived bristlecone pine species (Great Basic Bristlecone pine and foxtail pine), co-occurring limber pine, and the mountain pine beetle (MPB). I will talk about recent and going research examining (1) the plant volatile cues used by host-searching MPBs, (2) the terpene-based phloem defenses used against MPB larvae, and (3) tradeoffs between constitutive and induced defenses across these pine species. Understanding these interactions provides insight into the longevity of bristlecone pines, the implications for these species under climate change, and development of management tool to protect trees from bark beetles."

Runyon, based on the Montana State University (MSU) campus in Bozeman, received his bachelor's degree in biology and mathematics in 1998 from the University of Virginia's College at Wise, Va.; his master's degree in entomology from MSU in 2001; and his doctorate in entomology in 2008 from Pennsylvania State University Park, Pa.

In 2014, at a ceremony in Washington, D.C., he received the Presidential Early Career Award for Science and Engineering (PECASE), the highest honor bestowed by the U.S. government on science and engineering professionals in the early stages of their independent research careers.

Chris Fettig

"Bark beetles are a major disturbance in western forests," Fettig says in his abstract. "Several recent outbreaks of species such as mountain pine beetle, spruce beetle, and western pine beetle are among the most severe in recorded history. There is strong evidence that climate change has increased the impacts of bark beetles. For example, in California warming and exceptional drought resulted in mortality of more than a 100 million trees from 2014-2017. Much of this mortality was attributed to western pine beetle colonizing drought-stressed hosts. I will discuss observed and projected changes in climate, the direct and indirect effects of climate change on bark beetles and forests, and management actions that increase the resilience of forests to bark beetles and climate change."

Fettig received his bachelor's degree (1993) and a master's degree (1996) from Virginia Tech University, and his doctorate in forest entomology in 1999 from the University of Georgia.

Winter Seminars. Note that the Justin Runyon seminar is a specially scheduled seminar. The Chris Fettig seminar is part of the UC Davis Department of Entomology and Nematology's series of winter seminars, held on Wednesdays at 4:10 p.m. in 122 Briggs Hall.  Urban landscape entomologist Emily Meineke, assistant professor, coordinates the weekly seminars. (See schedule.) She may be reached at ekmeineke@ucdavis.edu for any technical issues. A coffee social precede each seminar in158 Briggs from 3:30 to 4:10 p.m.  

For general information about bark beetles, read the UC Statewide Integrated Pest Management Program's "How to Manage Pests in Gardens and Landscapes":

"Bark beetles, family Scolytidae, are common pests of conifers (such as pines) and some attack broadleaf trees. Over 600 species occur in the United States and Canada with approximately 200 in California alone...California now has 20 invasive species of bark beetles, of which 10 species have been discovered since 2002." The UC IPM information includes a chart of bark beetles common in landscapes.