Goals & Objectives:

Beech leaf disease (BLD) is a new tree disease spreading rapidly through forests across the Northeast, around the Great Lakes, and into Canada. It was first confirmed in two Michigan counties very recently – in summer 2022. This project focuses on providing information and recommendations on this new and damaging invasive disease, including:
1) Early detection of BLD in Michigan: surveying, mapping, and monitoring for occurrence and effects.
2) Building and bolstering a response network, through data sharing, educational communications and/or events, and interpretation of the rapidly-developing research on this disease and its vectors.
3) Contributing to cutting-edge research on the current and expected ecosystem impacts of this and other novel pests and pathogens.

Theoretical Justification, Social Benefit, or Significance:

Damage by introduced pests and pathogens poses a major risk to North American forests. Pests and disease have extensive and long-lasting ecological impacts in forest ecosystems, and pest pressure on forests can reduce tree diversity, overall resilience, and the forests’ capacity to provide ecosystem services. The most damaging introduced pest species are responsible for the loss of 5.53 Tg carbon annually (in the form of elevated mortality rates); 41.1% of the total live forest biomass in the continental United States is at risk of future losses. Tree decline and mortality also have major impacts in urban areas, where single trees are integrated into the fabric of urban life and replacement is often challenging. The risks to forest function and structure have become even more acute as climate change simultaneously impacts forest ecosystems and their ability to recover from stress and disturbance.

This MP focuses on the early stage spread of BLD in Michigan and across the range of American beech (Fagus sylvatica). As BLD rapidly spreads, it has great potential to interact with other impacts to forest ecosystems, including climate-driven stress, disease complexes, and mesophication trends in forests, ultimately altering essential ecological patterns and processes. Because BLD also causes damage to European, Japanese, and ornamental beech varieties, it has the potential to cause major damage in both urban and forested landscapes across the globe. There is precedent for dramatic socio-environmental impacts from humble forest pests: in the Eastern U.S., diseases have already decimated once-dominant tree species such as chestnut and American elm; spongy moth repeatedly defoliates hardwood forests; and the beech bark disease complex has hastened mortality in large, old trees, altering forest structure and composition and reducing carbon sequestration. In the forests of the Great Lakes region, just one introduced species, the emerald ash borer (EAB), has killed tens of millions of ash trees and dramatically transformed wetland forests and urban landscapes over the last twenty years. Assembling data and organizing a response to novel pests and pathogens presents many challenges. This is illustrated by the shortcomings of previous efforts, including attempts to contain EAB here in Southeast Michigan. Observing and monitoring the early-stage BLD invasion now underway will provide essential information, opening a key window of opportunity for forest managers to intervene and mobilize resources on behalf of individual trees and entire forest ecosystems.

Integrative Approach:

In this project, all team members will work together to synthesize a summary of the current status of BLD in Michigan and make recommendations for future monitoring, management, and research. Each team member will also lead or co-lead a product aligned with their interests and skills which will inform and support the group report. To start, all team members will collaborate on field surveys for BLD presence/absence surveys in forest and landscaped settings, which will lay the groundwork for the other project elements.

Specific Activities & Duration:

Approaches to this problem will include surveys of forested locations following previously established protocols (Martin et al 2019) and review of technical and policy approaches to invasive pest and pathogen management. It may also include designing or adapting survey protocols for urban and landscape trees. Preparation/timing: Survey work must take place during the growing season (May-September), while literature analysis, interpretation, and outreach components are not dependent on tree phenology. Tasks/deliverables were designed for execution by a MP team.