Ash Inventory and Management Options for Emerald Ash Borer Response

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Muth, Adam
Edwards, Graham
Mainolfi, Andrew
Kuers, Dr. Karen
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Scholarship Sewanee 2022 , University of the South , Forestry , Trees , Emerald Ash Borer , Insects , Economics
The invasive emerald ash borer (EAB, Agrilus planipennis F.) has eradicated populations of ash (Fraxinus sp.) trees across the United States. The major response options include tree removal and stem chemical treatments. To examine the potential impact of emerald ash borer on the ash trees in the Monteagle Sunday School Assembly (MSSA), in fall 2021 we inventoried all the ash trees on leaseholds and along trails. We mapped the tree location, and measured stem diameter at breast height (stems >2 inches), height (estimated and exact), percentage dieback of the crown, and general notes. Tree locations on leaseholds were approximately marked on paper maps for entry in ArcGIS software, and trees along trails were mapped with a GPS. The inventory identified 126 ash stems on leaseholds. One or more ash were found on 53 leaseholds, with some leaseholds having up to 12 stems. The ash had an average DBH of 14.8 inches. With respect to canopy dieback, one and two inch diameter dead branches were the most common, with the larger sizes being much less common. Ash trees become very brittle after infection, with the most common target of dead branches and trees being houses and powerlines. An inventory of trees in the MSSA commons in 2018 reported 54 additional ash stems, with an average DBH of 16.2 inches. Ash trees along the trails were more common below the bluff and showed that there are some large ash trees in striking distance of a trail. A comparison of the effectiveness, environmental considerations, and costs were made of stem removal and the two main chemicals available to treat EAB (imidacloprid and emamectin benzoate). Input was used from tree service providers, public land management agencies, and university resources. A management plan comparing treatment options is being prepared for MSSA. We recommend that the MSSA begin their response to EAB this year, and that they group sectors of the property for treatment or removal to reduce the overall cost of their response.