Sessions Sponsored by the Forest Pathology Committee at the
2006 APS Annual Meeting

Meeting was held July 29 - August 2, 2006, Center des congrés de Québec, Québec City, Québec, Canada

Forest Pathology Field Trip, co-sponsored by APS & CPS

Saturday, July 29, 7:30 a.m. – 6:00 p.m.

Sponsoring Committee: Forest Pathology
Organizer: Louis Bernier, Université Laval, Québec, QC, Canada
Registration Fee: $60

The field trip took participants to various locations in the St. Lawrence River Valley to visit natural forest stands and plantations, and to discuss several tree diseases and their management, including white pine blister rust, septoria canker and leaf rusts of hybrid poplars, larch diseases, Dutch elm disease, perennial nectria canker, and sapstain of wood.

Detection of Invasive Pathogens in Forest and Ornamental Landscapes

Section: Epidemiology/Ecology/Environmental Biology
Organizer: Jennifer Juzwik, USDA Forest Service, St. Paul, MN
Sponsoring Committees: Forest Pathology, Epidemiology, Diseases of Ornamental Plants, Regulatory Plant Pathology, Graduate Student

The cost of managing exotic invasive species increases exponentially across the continuum of prediction and prevention, early detection and rapid response, management and mitigation, and rehabilitation and restoration. Besides the associated lower cost, early detection of an invasive plant pathogen affords greater opportunity for eradication or geographic containment of a recently established species. Improved and integrated technologies for various steps in early detection and rapid response activities are needed to stem the tide of exotic invasions. This is particularly challenging for detection at the landscape to macroscale. This symposium will address the current and cutting edge knowledge from delimiting and prioritizing areas for early detection surveys to linkages between an early detection event and eliciting an early response to eradicate or contain the associated disease.

Statistical methodologies for early detection surveys in forest and ornamental landscapes. W. TURECHEK, USDA ARS, Beltsville, MD

Delimiting and prioritizing areas for early detection surveys in forest or ornamental landscapes. R. VENETTE, USDA Forest Service, St. Paul, MN

Application of spatial modeling for early detection of the emergent forest disease Sudden Oak Death. R. MEENTEMEYER, University of North Carolina, Charlotte, NC

Aerial and ground surveys in detection of invasive pathogens in forest landscapes. A. HOPKINS, Natural Resources Canada, Sault Ste. Marie, ON, Canada

Use of classical and molecular technologies in processing samples from early detection surveys. J. WILLIAMS-WOODWARD, University of Georgia, Athens, GA

Linkages between early detection and early response to invasive pathogens. T. GOTTWALD, USDA-ARS, Fort Pierce, FL


Urban Forestry Health Management

Section: Plant Disease Management
Organizer: Daniel Collins, Southern University, Baton Rouge, LA
Sponsoring Committee: Forest Pathology

Urban forestry can be defined as the science, technology and art of managing trees and natural systems in and around urban environments. Trees and forests play an important role in the function and health of urban natural ecosystems by, improving air and water quality, protecting urban watersheds, creating wildlife habitat, and contributing to a community’s economy and way of life. Plant diseases and environmental stressors are threats to the health of the urban forest. This symposium will include presentations on the latest research, education, extension, and outreach activities in the United States and Canada addressing urban forestry health management issues.

Introduction. D. COLLINS, Southern University, Baton Rouge, LA

Selection of American elms resistant to Dutch elm disease. M. HUBBES, University of Toronto, Toronto, ON, Canada

There goes the neighborhood: How Canadian cities are trying to cope with exotic pathogens and pest. L. BERNIER, Laval University, Québec, QC, Canada

Assessing urban forest structure and function in Gulfport, Mississippi. K. ABDOLLAHI, Southern University, Baton Rouge, LA

On oaks felled by sudden oak death: How this disease impacted urban forest management. P. SVIHRA, University of California, Berkeley, CA

Exotic pathogens and angry endophytes: Challenges to urban forest in California. T. GORDON, University of California, Davis, CA

Paper birch mycorrhizae in simulated urban soils: A case study for needs, impact, and concerns. N. KLECZEWSKI, Ohio State University, Columbus, OH

Management of powdery mildew diseases of ornamentals. M. MMBUGA, Tennessee State University, Knoxville, TN

Urban forestry health management issues: A Canadian west coast perspective. M. GORMAN, City of Victoria, Victoria, BC, Canada

Impact of oak wilt on urban forest in Texas. D. APPEL, Texas A&M University, College Station, TX

Utilizing urban wood waste to improve urban forest health. A. JOHNSON, Southern University, Baton Rouge, LA

Detecting Phytophthora ramorum in the urban forest interface. J. JONES, USDA-APHIS, Riverdale, MD

Current and emerging threats to urban forests in the upper Midwest. J. JUZWIK, USDA Forest Service, St. Paul, MN

From the forest to the field: The ultimate challenge for urban trees. G. HUDLER, Cornell University, Ithaca, NY


Fungal Endophytes: Diversity and Function in Forest Ecosystems

Section: Biology of Plant Pathogens
Organizers: Ned Klopfenstein, USDA Forest Service, Moscow, ID; Mee-Sook Kim, USDA Forest Service, Moscow, ID; Richard Hamelin, Canadian Forest Service, Québec, QC, Canada
Sponsoring Committees: Forest Pathology, Mycology

Ecological roles of fungal endophytes are an understudied aspect of forest ecosystem processes. This symposium will address 1) taxonomic diversity, 2) interactions with pathogens and insects, and 3) interactions with other environmental factors (e.g., temperature, moisture, nutrition, and fire).

General aspects of grass endophytes: A baseline for comparing endophytes of wood. C. SCHARDL, University of Kentucky, Lexington, KY

Ecological roles of endophytes in forest ecosystems. J. STONE, Oregon State University, Corvallis, OR

From the leaf to the landscape: Endophyte diversity and interactions at small and large spatial scales. A.E. ARNOLD, University of Arizona, Tucson, AZ

Fungal endophytes of pine needles: Biocontrol implications. J. BÉRUBÉ, Canadian Forest Service, Québec, QC, Canada

Endophytes from roots of Douglas-fir and ponderosa pine on burned sites. G. GOETZ, Washington State University, Pullman, WA

Latent fungal pathogens of woody plants: Power that has not yet come forth! G. STANOSZ, University of Wisconsin, Madison, WI


Long-Term Patterns of Spread and Intensification for Forest Pathogens

Section: Epidemiology/Ecology/Environmental Biology
Organizers: Paul Zambino, Moscow, ID; John Lundquist, USDA Forest Service, Ft. Collins,CO; Ned Klopfenstein, USDA Forest Service, Moscow, ID
Sponsoring Committees: Forest Pathology, Epidemiology

Landscape pathology is an emerging field that aims at integrating the concepts and tools of landscape ecology with forest pathology. This session will examine landscape-scale and long term patterns of spread and intensification of several forest pathosystems. These pathosystems typically have long-lived hosts, persistent ecosystems, and heterogeneous geographical features, which strongly contrasts with cropping systems. Efforts to describe and understand the occurrence, distribution, and dynamics of exotic and native forest pathogens in diseased landscapes will be presented.

Application of GIS and geostatistics to epidemics in natural systems. F. NUTTER, Iowa State University, Ames, IA

Effects of landscape heterogeneity and land-cover changes on the emerging forest disease sudden oak death. R. MEENTEMEYER, University of North Carolina, Charlotte, NC

Parameters in large-scale dissemination and landscape suitability in recent spread of white pine blister rust in North America. K. FRANK, University of Delaware, Newark, DE

Beech bark disease spread and intensification in eastern hardwood forests of North America. M. MACKENZIE, USDA Forest Service, Morgantown, WV

Factors affecting the spread of swiss needle cast in the Pacific Northwest. J. KERRIGAN, Oregon State University, Corvallis, OR

Predictive modeling of landscape-scale dwarf mistletoe patterns. J. LUNDQUIST, USDA Forest Service, Ft. Collins, CO


Phytophthora ramorum: An Environmental Threat; A Regulatory Quandary

Section: Epidemiology/Ecology/Environmental Biology
Organizer: Christel Harden, Clemson University, Pendleton, SC
Sponsoring Committees: Regulatory Plant Pathology, Diseases of Ornamental Plants, Forest Pathology

Phytophthora ramorum, often called “Sudden Oak Death,” poses a threat to the green industry and forest ecosystems of North America. Since 1995, oaks and tanoaks in California and Oregon have been dying due to infection with P. ramorum, a pathogen first identified in 1993 on ornamentals in Europe. While the extent of the host range is not completely understood, the pathogen is known to infect at least 68 species of trees and ornamentals. Shipments of infected nursery stock have disseminated P. ramorum through the United States. Export of nursery stock from California and Oregon has been restricted. In 2004, USDA published regulations limiting the movement of host and associated plants from infested counties. Due to the serious potential for spread of P. ramorum to landscapes and hardwood forests in uninfested parts of the United States and Canada, quarantines have been established to limit the pathogen’s movement. While justified, such phytosanitary measures negatively affect the nursery industry by preventing the sale of ornamentals from western producers and impacting the availability of nursery stock to other areas of the continent. Because P. ramorum was identified relatively recently, there is limited scientific knowledge about its biology, transmission, epidemiology, and diagnostics, which makes development of an effective regulatory program difficult. This session will provide perspective about the issues and challenges of managing Phytothphora ramorum.

Survey and Diagnosis of Phytophthora ramorum – An update. S. JEFFERS, Clemson University, Clemson, SC

Environmental concerns surrounding Phytophthora ramorum. S. OAK, USDA Forest Service, Asheville, NC

Impact of Phytophthora ramorum upon regulatory activities in western states. N. OSTERBAUER, Oregon Department of Agriculture, Salem, OR

Impact of Phytophthora ramorum upon regulatory activities in eastern states. C. ROUSSEL, Louisiana Department of Agriculture and Forestry. Baton Rouge, LA

Regulatory concerns surrounding Phytophthora ramorum in Canada. R. ORMROD, Canadian Food Inspection Agency, Kelowna, BC, Canada


The Effects of Climate Change on Tree Diseases

(Not sponsored by Forest Pathology Committee, since this was a CPS session)

Section/Sponsor: Canadian Phytopathological Society
Organizer: Anthony Hopkins, Natural Resources Canada, Sault Ste. Marie, ON, Canada
Financial Sponsor: Natural Resources Canada, Climate Change Action Fund

The activities of insects and diseases greatly influence the structure and function of forest ecosystems from regeneration through mortality. The relationship between climate and plant disease is well established, though there has been little attention paid to the link between climate change and tree diseases. While global warming might influence the distribution and abundance of diseases, our ability to identify and predict these factors is limited. On this basis, working to understand and monitor diseases is an important part of Canada’s work to manage for climate change impacts. Proposed climate change scenarios, which include warmer winter temperatures and more frequent droughts in some locations, will affect the occurrence of plant diseases in forests. Climatic change could influence the epidemiology of plant diseases through effects on survival of primary inoculum, rate of disease progress during the growing season, and duration of epidemics. These effects will positively or negatively influence individual pathogens directly or through the interactions between diseases and abiotic events such as drought or storm damage. The symposium on the Effects of Climate Change of Forest Diseases will illustrate through case studies the potential impact of a changing climate on diseases of forest trees in North America and Europe.

Is an unprecedented Dothistroma needle blight epidemic related to climate change? A. WOODS, Regional British Columbia Ministry of Forests, Smithers, BC, Canada

Predicting effects of climate change on Swiss needle cast disease severity in the Pacific Northwest. J. K. STONE, Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR

Simulating potential effects of climate change on geographic range and activity of forest pathogenic fungi in Europe. M. L. LOUSTAU, Equipe de Pathologie forestière, INRA, Villenave d’Ornon, France

New trends in forest emerging pathogens under climate change condition in Europe. N. LA PORTA, Department of Natural Resources, Agricultural Institute, S. Michele all’Adige, Italy.