Oak Wilt

Research Issue

[photo:] As of 2016, current known distribution of oak wilt in the United States (2016).  Source: Q. Chavez, NA S&PF, U.S. Forest Service.Oak wilt is one of the most serious diseases of oak trees (Quercus species) in the eastern USA. Caused by the fungus Ceratocystis fagacearum, the disease kills hundreds of thousands of oaks in the upper Midwest every year. In 2008, oak wilt was found for the first time in upstate New York and on Long Island, NY. These new finds are more than 200 miles from the nearest known disease centers in Pennsylvania. The geographic origin of the fungus is unknown.

[photo:] Oak wilt crown symptoms in northern red oak (left) and bur oak (right). Photo credit: J. Juzwik, NRS, U.S. Forest Service. The oak wilt fungus spreads from diseased to healthy trees both above- and below-ground. Sap beetles pick up spores of the fungus on infected trees and carry them to areas of damaged bark on healthy trees. Underground, the fungus can be spread through the intertwined root systems of neighboring trees. New or improved management tools are needed to break the above- and below-ground disease cycles.

Our Research

Our oak wilt research ranges from basic scientific studies in the laboratory to applied field research experiments. We often work in collaboration with university and industry colleagues. Here are brief descriptions of active projects:

  1. New methods for early and accurate detection of the oak wilt fungus in oaks - A novel method of direct DNA detection using nano-technology is undergoing development and testing.
  2. Testing of fungi-killing chemicals (fungicides) for their effectiveness on the oak wilt fungi – Collaborative research with an industry partner is also studying different methods of injecting fungicide into oaks.
  3. Improved prediction of the above-ground pathogen transmission by sap beetle species – Timing of the dispersal of two species of sap beetles (or nitidulid beetles) in different regions of Wisconsin was investigated using insect pheromone-baited funnel traps. Degree-day models were then developed to evaluate existing “no-pruning” or “no harvesting” time periods.
  4. Refined guidelines for stopping below-ground transmission of the oak wilt pathogen using a vibratory plow – Evaluation of a “double plow line” (separated by about one foot) technique applied using a modified “rule of thumb” model developed in Minnesota is underway in long-term study plots in East Central Minnesota. “Single plow line” plots are being used for comparison. All sites are on sandy soils in flat to rolling terrain.
  5. Early detection of oak wilt in forest landscapes using hyperspectral sensors – Greenhouse and field studies are underway to evaluate the utility and early detection ability of oak wilt using remotely sensed hyperspectral imagery in oak stands with known oak wilt.

Expected Outcomes

Our goal is to better understand how oak wilt spreads and how the disease progresses inside individual trees. We want to help develop new tools for integrated management of oak wilt that can be used by urban and community foresters, arborists, and natural resource managers of public lands. We are also working to develop improved detection tools for use by plant disease specialists and people who work directly with trees in the field.

Research Results

Jagemann, Stephanie M; Juzwik, Jennifer; Tobin, Patrick C; Raffa, Kenneth F. 2018. Seasonal and Regional Distributions, Degree-Day Models, and Phoresy Rates of the Major Sap Beetle (Coleoptera: Nitidulidae) Vectors of the Oak Wilt Fungus, Bretziella fagacearum, in Wisconsin. Environmental Entomology. 47(5): 1152-1164. https://doi.org/10.1093/ee/nvy080.

Juzwik, Jennifer; Yang, Anna; Chen, Zhangjing; White, Marshall S.; Shugrue, Sarah; Mack, Ronald. 2019. Vacuum Steam Treatment Eradicates Viable Bretziella fagacearum from Logs Cut from Wilted Quercus rubra . Plant Disease. 103(2): 276-283. https://doi.org/10.1094/PDIS-07-18-1252-RE.

Yang, A.; Juzwik, J. 2017. Use of Nested and Real-Time PCR for the Detection of Ceratocystis fagacearum in the Sapwood of Diseased Oak Species in Minnesota. Plant Disease. 101(3): 480-486. https://doi.org/10.1094/PDIS-07-16-0990-RE.

Singh, Renu; Feltmeyer, Alexandra; Saiapina, Olga; Juzwik, Jennifer; Arenz, Brett; Abbas, Abdennour. 2017. Rapid and PCR-free DNA detection by nanoaggregation-enhanced chemiluminescence. Scientific Reports. 7(1): 14011. 9 p. https://doi.org/10.1038/s41598-017-14580-w.

Yang, A.; Juzwik, J. 2017. Use of Nested and Real-Time PCR for the Detection of Ceratocystis fagacearum in the Sapwood of Diseased Oak Species in Minnesota. Plant Disease.

Juzwik, J.; Appel, D.N. 2016. 35. Oak wilt. Pp. 129-133. In:  Diseases of Trees in the Great Plains. Bergdahl, A., and Hill, A. (tech. coords.). GTR-RMRS-335. Ft. Collins, CO: USDA Forest Service. 

Juzwik, J.; Schwingle, B.; Russell, M. 2015. Oak wilt in Minnesota. St. Paul, MN: University of Minnesota Extension, Extension Center for Agriculture, Food and Natural Resources – Forestry.

Juzwik, Jennifer; Appel, David N.; MacDonald, William L.; Burks, Susan. 2011. Challenges and successes in managing oak wilt in the United States. Plant Disease. 95(8): 888-900.

O’Brien, J.G.; Mielke, M.E.; Starkey, D.; Juzwik, J. 2011. How to identify, prevent and control oak wilt. NA-FR-01-11. Newtown Square, PA: USDA Forest Service, Northeastern Area State and Private Forestry.

Blaedow, Ryan A.; Juzwik, Jennifer. 2010. Spatial and temporal distribution of Ceratocystis fagacearum in roots and root grafts of oak wilt affected red oaks. Arboriculture & Urban Forestry. 36(1): 28-34.

Blaedow, Ryan A.; Juzwik, Jennifer; Barber, Brian. 2010. Propiconazole distribution and effects on Ceratocystis fagacearum survival in roots of treated red oaks. Phytopathology. 100(10): 979-985.

Juzwik, Jennifer; Cummings-Carlson, Jane; Scanlon, Kyoko. 2010. Risk analysis and guidelines for harvest activities in wisconsin oak timberlands to minimize oak wilt threat. In: Pye, John M.; Rauscher, H. Michael; Sands, Yasmeen; Lee, Danny C.; Beatty, Jerome S., tech. eds. Advances in threat assessment and their application to forest and rangeland management. Gen. Tech. Rep. PNW-GTR-802. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest and Southern Research Stations: 599-607.

Juzwik, Jennifer; O'Brien, Joseph; Evenson, Charles; Castillo, Paul; Mahal, Graham. 2010. Controlling spread of the oak wilt pathogen (Ceratocystis fagacearum) in a Minnesota urban forest park reserve.

Research Participants

Principal Investigators

Post-Docs (formerly)

Graduate Students

  • Beth Fallon (formerly Ph.D. student)
  • Alex Feltmeyer (current M.S. student)
  • Stephanie Jagemann (formerly M.S. student)
  • Anna Yang, University of Minnesota (formerly M.S. student)

Research Partners

  • Last modified: March 19, 2019