Scientists & Staff

Dr. Jessie A. Glaeser (photo by T.J. Volk)

Jessie A. Glaeser

Research Plant Pathologist
One Gifford Pinchot Drive
Madison, WI, 53726
Phone: 608-231-9215

Contact Jessie A. Glaeser

Current Research

• Decontamination protocols to prevent human transmission of Pseudogymnoascus destructans, the causal agent of white-nose syndrome of bats.
• Assessing temperature optima of forest fungi to predict their adaptability to climate change.
• Wood decay fungi and hazard tree assessment.
• Growth of wood decay fungi in wood-plastic composites.
• Identification and biosystematics of brown-rot wood decay fungi.
• Risk and pathway assessment for the introduction of exotic pathogens that could affect Hawaii's native forests.

Research Interests

• Biology, ecology and management of invasive and native forest fungal pathogens.
• Effect of climate change on the distribution and adaptability of forest fungi.
• Decay colonization patterns of wood and the development of spalting patterns.
• Movement and establishment of invasive fungal species.
• White-nose syndrome of bats.

Past Research

• The resolution of the Endothia and Cryphonectria controversy, including a reassessment and final taxonomic disposition of the chestnut blight pathogen, Cryphonectria parasitica.
• Biosystematics of Peronosclerospora species – potentially invasive pathogens of corn and sugar cane.
• Physiology of brown rot decay.
• The decomposition of forest products in landfills.
• The use of wood extractives for the control of wood decay fungi.
• Development of preventative and remedial mold treatments for building materials.
• Decay fungi and forest health - decay patterns of Lutz spruce in Alaska.
• Pest risk assessments of importing pine and eucalyptus logs and wood chips from Australia.
• Fungal biodiversity and climate change.
• Assessment of the distribution of Heterobasidion irregulare in the Upper Midwest (USA).

Why This Research is Important

Certain fungi are pathogenic to trees and forest wildlife, causing losses in forest ecosystems and forest productivity. Under ordinary conditions, forests are well suited to survive and thrive, even when exposed to organisms that cause disease or to episodes of environmental stress. The introduction of invasive pathogens, for which native organisms have no inherent genetic resistance, can result in massive loss of productivity and devastation to forest ecosystems. Invasive species are often introduced from other countries or from other ecosystems within the US. A thorough study of pathways associated with the introduction of potentially invasive insects and pathogens is needed to prevent tree death and decline.

Fungi are also the main decomposers of wood and leaf litter – these fungi are termed “saprotrophs.” Decayed wood and leaves contribute to soil organic matter, and hence directly to soil carbon sequestration. Decay products also indirectly contribute to carbon sequestration through positive effects on soil fertility and forest productivity. In most forests, the impact of forest management on the populations and functions of these pathogenic and nutrient-cycling fungi is unknown. Accurate identification of the fungal species involved, their relationships, and their biological activity are required to understand and assess the impacts of forest management practices, invasive species, and global climate change on forest health and productivity.The fungi associated with urban forests also need to be characterized.This knowledge is beneficial to arborists who must perform hazard tree assessments.

Pseudogymnoascus destructans, the causal agent of White Nose Syndrome, has killed over 6 million bats in eastern North America since the disease was first observed in 2006. Bats are a critical component of the ecosystem, primarily because of their impact on insect populations. One possible mode of pathogen transmission is human-mediated movement among hibernacula (caves and mines) – e.g., on the shoes, clothes and equipment of tourists and the caving community. Efficient and inexpensive protocols are necessary for cave visitors to clean their clothing and equipment to prevent transmission of this devastating pathogen.


  • Virginia Polytechnic Institute and State University, Ph.D. Plant Pathology., 1985
  • Delaware Valley College of Science and Agriculture, Doylestown, PA., B.S. Agronomy., 1979

Professional Experience

  • Research Plant Pathologist/Supervisory Plant Pathologist, U.S. Forest Service, Forest Products Laboratory/Northern Research Station, Madison, WI 1985 - Current
  • Post-doctoral Research Associate, Cornell University, stationed at ARS facility, Forest Detrick, Frederick, MD. 1984 - 1985

Professional Organizations

  • International Society of Arboriculture (2010 - Current)
    Invited speaker at regional and international meetings.
  • Western International Forest Disease Working Committee (1998 - Current)
    Root Disease Committee, Hazard Tree Committee, Climate Change Committee, Symposium Organizer.
    Secretary and member of the program committee of the Hazard Tree Committee. Involved with organizing Hazard Tree Workshops (2010, 2013, 2016).
  • International Biodeterioration and Biodegradation Society (1997 - Current)
    Member of the Editorial Board. Responsible for reviewing submitted manuscripts for International Biodeterioration and Biodegradation Journal.
  • Mycological Society of America (1986 - Current)
    Program Committee, Endowment Committee, Sustaining Membership Committee
    Served as Executive Vice President from 2009-2012. Responsible for all correspondence and documentation of business meetings and worked to ensure smooth administrative operation of the Society.

Awards & Recognition

  • Mycological Society of America - Fellow Award, 2015 For outstanding contribution to mycology and service to the Mycological Society of America.
  • US Forest Service Spot Award, 2015 For team leadership.
  • USDA Certificate of Merit, 2014 Secretary of NRS Civil Rights Committee (2011-2014).
  • US Forest Service Spot Award, 2013 For team leadership.
  • USDA Certificate of Merit, 2006 Team award for customer service.
  • USDA Certificate of Merit, 2005 Team award for customer service.
  • USDA Certificate of Merit, 2004 Civil Rights
  • USDA-Animal Plant Health Inspection Service Certificate of Merit, 2001 "For commitment to safeguarding demonstrated by contributions as a member of the Science and Technology Committee."
  • USDA Certificate of Merit, 1998 For exceeding requirements of the position.
  • USDA Certificate of Merit, 1996 For exceeding the requirements of the position.
  • USDA Certificate of Merit, 1995 For exceeding requirements of the position.
  • USDA Certificate of Merit, 1994 For exceeding requirements of the position.
  • USDA Certificate of Merit, 1992 From WO staff for writing "Good Laboratory Practices" chapters for Forest Service Handbook and Manual.
  • USDA Certificate of Merit, 1990 For service as Federal Women's Program Manager.
  • Cunningham Foundation Graduate Research Fellowship, 1983 Stipend provided for continuing graduate studies.
  • National Science Foundation Graduate Fellowship, 1979 Stipend award for graduate studies.

Featured Publications & Products

Publications & Products

National Research Highlights

Hawaii’s native forest, Oahu, Hawaii.

Team assesses invasive species threat to Hawaii and other U.S. ports of entry

Year: 2017

Introduced through pathways of international trade and tourism, invasive insects and pathogens can strike anywhere. The Hawaiian Islands are especially vulnerable due to their dependence on trade with foreign countries and the mainland. Forest Service researchers, working with the U.S. Forest Service Wood Import and Pest Risk Assessment Mitigation and Evaluation Team (WIPRAMET), evaluated the risk of introducing nonnative pests that could endanger native Hawaiian plants. Lessons from this analysis are applicable to other U.S. ports of entry.

Figure 1: Spores of Pseudogymnoascus destructans, magnified one thousand times.. Curved spores are the most characteristic, but they are often highly variable in shape.
Figure 2: Efficacy of 70 percent ethanol on spore survival. Top row: Growth after exposure to ethanol for 0, 0.3 and 1 minute.  Row 2: Growth after 5, 10 and 15 minutes.

Preventing human-based transmission of white-nose syndrome of bats.

Year: 2017

Over six million bats have died in eastern North America from white-nose syndrome since the disease was first observed in 2006. Forest Service scientists are looking for ways to slow the spread of the disease by finding better ways to clean the clothing and equipment that people bring into the caves.

DAME crystals on a smoldering mesquite tree in Alamo Canyon, ArizLaurence A. J. Garvie, Arizona State University

Wood Decay Fungus Forms Toxic Organohalogen Crystals in Mesquite

Year: 2015

A Forest Service scientist identified toxic organohalogen crystals formed by fungi in decaying mesquite. Charcoal production and forest fires in the Southwest could release significant quantities of this compound into the atmosphere.

Tree failure resulting in damage to house, Kennebunkport, ME. USDA Forest Service

Managing Wood Decay in the Urban Forest

Year: 2014

Arborists need tools to help identify patterns of wood decay as part of tree risk analysis and decisions on the proper care of urban and community trees. Forest Service scientists prepared a series of articles to introduce arborists to frequently encountered decay fungi and patterns of decay in common oak and riparian tree species.

Heterobasidion root rot in red pine. Jessie Glaeser, USDA Forest Service

Detection of Heterbasidion Root Disease Using Genetic Fingerprinting

Year: 2013

Heterobasidion root rot is a significant pathogen in the red pine plantations of the midwestern U.S. Little is known about its distribution. Forest Service scientists developed a DNA molecular test for field personnel to use in diagnosing the disease.

Living fungal cultures stored in liquid nitrogen in the CFMR culture collection (photo by S. Schmeiding, USFS). Examining specimens in the CFMR herbarium. S. Schmeiding, Forest Service

Web-enabled Database for Center for Forest Mycology Research Expanded

Year: 2010

The culture collection and herbarium maintained by the Center of Forest Mycology Research (CFMR) in Madison, Wisconsin is one of the largest fungal 'libraries' in the world. The collection specializes in fungi associated with wood and contains both living fungi and dried reference specimens, which are used by researchers world-wide in studying forest pathology, disturbance biology, fungal genetics, distribution of invasive species, and impact of climate change on forest ecosystems. The CFMR's web-enabled database, accessible at, has recently been enlarged and updated.

DNA Tool Detects White-Nose Syndrome Fungus in Bat Caves

Year: 2010

NRS scientists Daniel Lindner and Jessie Glaeser are collaborating with the USGS Wildlife Health Laboratory in Madison, WI, to characterize the distribution of G. destructans in cave sediment samples from bat hibernation sites in the eastern United States.

Last modified: Tuesday, August 18, 2015