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Northern Research Station
One Gifford Pinchot Drive
Madison, WI 53726
(608) 231-9318
(608) 231-9544 TTY/TDD

Emerald Ash Borer

Ash Tree Health Index

[photo:] EAB infested ash tree top with dying foliageResearch Issue

Emerald Ash Borer (Agrilus planipennis, eab), an invasive insect native to Southeast Asia, is responsible for killing millions of Ash (Fraxinus) trees throughout much of the mid west. As of May 2009, the insect occupies the states of Illinois, Indiana, Kentucky, Maryland, Michigan, Minnesota, Missouri, Ohio, Pennsylvania, Virginia, West Virginia, Wisconsin, and parts of Canada.

Detection of Emerald Ash Borer infestations are difficult when trees are first attacked, showing few signs that eab is present. Visual surveys in urban environments can under estimate the severity of the infestation, due to their subjective nature. Quantification of known symptoms related to the presence of eab would provide better monitoring of tree health.

Our Research

We have developed a Ash Tree Health Index (ATHI) classification scheme based on data collected from 45 green ash (Fraxinus pennsylvanica) street trees from Toledo, OH. ATHI is calculated by weighting the number of epicormic shoots, the number of D-shaped exit holes, and the canopy light transmission. 

  • Information about calculating ATHI.

Expected Outcomes

  1. Better evaluation methods for the detection of eab that will provide homeowners and property managers information which to base management options including tree removal, replacement, and pesticide usage.
  2. Improved management can slow the spread of eab in particular areas.
  3. Earlier removal of outlier infested trees might help to contain the eab population until a better method of eradication is available.

Research Results

Peters, M.P.; Iverson, L.R.; Sydnor, T.D. 2009. Emerald Ash Borer (Agrilus planipennis): Towards a Classification of Tree Health and Early Detection. Ohio Journal of Science 109: 15-25.

Research Participants

Principal Investigators

  • Matthew Peters, US Forest Service – Northern Research Station GIS Analyst
  • Louis Iverson, US Forest Service – Northern Research Station Landscape Ecologist
  • Davis Sydnor, Ohio State University

Research Partners

  • City of Toledo, Ohio - Department of Parks, Recreation and Forestry

Last Modified: 09/16/2015