Charles E. Flower
Research Ecologist
Genetics, Biological Control, and Management of Invasive Species
359 Main Road
Delaware, OH 43015-8640
United States
Delaware, OH 43015-8640
United States
Phone
740-368-0038
Education
- University of Illinois at Chicago, Ph.D., Biological Sciences, 2013
- The Ohio State University, M.S., Ecology, Evolution and Organismal Biology, 2007
- Lake Forest College, B.A., Biology and History, 2004
Featured Publications
- Flower, Charles E.; Long, Lawrence C.; Knight, Kathleen S.; Rebbeck, Joanne; Brown, Joel S.; Gonzalez-Meler, Miquel A.; Whelan, Christopher J.. 2014. Native bark-foraging birds preferentially forage in infected ash (Fraxinus spp.) and prove effective predators of the invasive emerald ash borer (Agrilus planipennis Fairmaire)
- Flower, Charles E.; Knight, Kathleen S.; Rebbeck, Joanne; Gonzalez-Meler, Miquel A.. 2013. The relationship between the emerald ash borer (Agrilus planipennis) and ash (Fraxinus spp.) tree decline: Using visual canopy condition assessments and leaf isotope measurements to assess pest damage
- Flower, Charles E.; Knight, Kathleen S.; Gonzalez-Meler, Miquel. 2013. Impacts of the emerald ash borer (Agrilus planipennis Fairmaire) induced ash (Fraxinus spp.) mortality on forest carbon cycling and successional dynamics in the eastern United States
Other Publications
- Reed, Samuel P.; Royo, Alejandro A.; Fotis, Alexander T.; Knight, Kathleen S.; Flower, Charles E.; Curtis, Peter S.. 2021. The long term impacts of deer herbivory in determining temperate forest stand and canopy structural complexity
- Flower, Charles E.; Pinchot, Cornelia C.; Knight, Kathleen S.; Woeste, Keith ; Slavicek, James M.. 2020. Back from the Brink: Forest Service Efforts to Create Dutch Elm Disease Tolerant Trees for Use in Urban and Rural Restoration
- Knight, Kathleen ; Kappler, Rachel H.; Root, Karen V; Koch, Jennifer L.; Flower, Charles E.. 2020. Monitoring of Ash Mortality Patterns Informs Emerald Ash Borer (EAB) Resistance Breeding Efforts: Integrated Pest Management for EAB
- Kıbış, Eyyüb Y.; Büyüktahtakın, İ Esra; Haight, Robert G.; Akhundov, Najmaddin ; Knight, Kathleen ; Flower, Charles E.. 2021. A Multistage Stochastic Programming Approach to the Optimal Surveillance and Control of the Emerald Ash Borer in Cities
- Flower, Charles E.; Dalton, Jennifer E.; Whelan, Christopher J.; Brown, Joel S.; Gonzalez-Meler, Miquel A.. 2019. Patch use in the arctic ground squirrel: effects of micro-topography and shrub encroachment in the Arctic Circle
- Knight, Kathleen S.; Flower, Charles E.; Nelson, Mark D.. 2019. A Forest Death in Three Acts: From Woodpeckers to Water, the Emerald Ash Borer's Effects are Widespread
- Flower, Charles E.; Lynch, Douglas J.; Knight, Kathleen S.; Gonzalez-Meler, Miquel A. . 2018. Biotic and Abiotic Drivers of Sap Flux in Mature Green Ash Trees (Fraxinus pennsylvanica) Experiencing Varying Levels of Emerald Ash Borer (Agrilus planipennis) Infestation
- Flower, Charles; Fant, Jeremie; Hoban, Sean; Knight, Kathleen; Steger, Laura; Aubihl, Elijah; Gonzalez-Meler, Miquel; Forry, Stephen; Hille, Andrea; Royo, Alejandro. 2018. Optimizing conservation strategies for a threatened tree species: In situ conservation of white ash (Fraxinus americana L.) genetic diversity through insecticide treatment
- Ricketts, Michael P.; Flower, Charles E.; Knight, Kathleen S.; Gonzalez-Meler, Miquel A.. 2018. Evidence of Ash Tree (Fraxinus spp.) Specific Associations with Soil Bacterial Community Structure and Functional Capacity
- Pinchot, C.C.; Lodge, D.J.; Minocha, R.; Noon, T.W.; D’Amico, V.; Flower, C.; Knight, K.M.; Slavicek, J.. 2017. Using American elm in mixed-species plantings to restore above- and below-ground function to degraded riparian buffers
- Flower, Charles E.; Aubihl, Elijah; Fant, Jeremie; Forry, Stephen; Hille, Andrea; Knight, Kathleen S.; Oldland, William K.; Royo, Alejandro A.; Turcotte, Richard M.. 2017. In-situ genetic conservation of white ash (Fraxinus americana) at the Allegheny national forest
- Pinchot, C.C.; Flower, C.E.; Knight, K.S.; Marks, C.; Minocha, R.; Lesser, D.; Woeste, K.; Schaberg, P.G.; Baldwin, B.; Delatte, D.M.; Fox, T.D.; Hayes-Plazolles, N.; Held, B.; Lehtoma, K.; Long, S.; Mattix, S.; Sipes, A.; Slavicek, J.M.. 2017. Development of new Dutch Elm disease-tolerant selections for restoration of the American Elm in urban and forested landscapes
- Flower, Charles E.; Pinchot, Cornelia C.; Slavicek, James M.. 2017. Restoring ecosystem resilience to urban forests using Dutch elm disease-tolerant American elm trees
- Flower, Charles E.; Hayes-Plazolles, Nancy; Rosa, Cristina; Slavicek, James M.. 2017. Elm yellows: a widespread and overlooked killer of elm trees across the United States
- Flower, Charles E.; Slavicek, James M.; Lesser, Dale; Eshita, Steven; Pinchot, Cornelia C.. 2017. Canopy decline assessment in American elm after inoculation with different doses of Ophiostoma ulmi and O. novo-ulmi
- Pinchot, Cornelia C.; Knight, Kathleen S.; Haugen, Linda M.; Flower, Charles E.; Slavicek, James M., eds... 2017. Proceedings of the American elm restoration workshop 2016
- Flower, Charles E.; Dalton, Jennifer E.; Knight, Kathleen S.; Brikha, Marie; Gonzalez-Meler, Miquel A.. 2015. To treat or not to treat: Diminishing effectiveness of emamectin benzoate tree injections in ash trees heavily infested by emerald ash borer
- Costilow, K.C.; Knight, Kathleen; Flower, Charles. 2017. Disturbance severity and canopy position control the radial growth response of maple trees (Acer spp.) in forests of northwest Ohio impacted by emerald ash borer (Agrilus planipennis)
- Knight, Kathleen S.; Flash, Britton P.; Kappler, Rachel H.; Throckmorton, Joel A.; Grafton, Bernadette; Flower, Charles E.. 2014. Monitoring ash (Fraxinus spp.) decline and emerald ash borer (Agrilus planipennis) symptoms in infested areas
- Flower, Charles E.; Lynch, Douglas J.; Knight, Kathleen S.; Gonzales-Meler, Miquel A.. 2011. EAB induced tree mortality impacts ecosystem respiration and tree water use in an experimental forest
Research Highlights

Understanding Long-Term Impacts of an Invasive, Tree-Killing Pest
Year: 2019
The emerald ash borer has been killing ash trees in the United States for more than two decades. What does that mean for ash populations and the forest ecosystems? Long-term monitoring plot data collected by USDA Forest Service scientists and partners is helping to elucidate the impacts of this inva...

Genetic Information on Ash Informs Treatments for Emerald Ash Borer
Year: 2018
Forest managers can use insecticide treatments to protect ash trees from emerald ash borer to conserve the genetic diversity of ash. But which trees should be protected? Research at the Allegheny National Forest is underway to develop new strategies to conserve ash tree diversity.

Forest Service moves American elm tree a big step closer to landscape restoration
Year: 2017
Over the past several decades, mature American elm trees have virtually disappeared from city streets and eastern forests as a result of Dutch elm disease. Forest Service scientists are on the cusp of developing sufficient genotypes to successfully restore new selections of American elm back to the ...

Identification of a clover proliferation group phytoplasma as the probable cause of American elm Ttee mortality
Year: 2017
Forest Service scientists observed premature canopy decline symptoms in elm trees within their research plantations in midsummer 2016. They attributed canopy decline symptoms to a phytoplasma in the clover proliferation group previously not reported to impact forest trees. Mitigation approaches are ...

Forest Service scientists develop a cold-hardy American elm tree
Year: 2017
Dutch elm disease largely eradicated mature elm trees from the eastern U.S. in the 1900s. Forest Service scientists are working to create site-adapted Dutch elm disease tolerant elm trees capable of tolerating the cold winters of the Chippewa National Forest in northern Minnesota.

Understanding effects of emerald ash borer on forests
Year: 2017
As the invasive emerald ash borer swept across Ohio, Forest Service researchers tracked its aftermath as killed ash trees unleashed a cascade of effects in forest ecosystems. Understanding these effects will help managers plan for and mitigate problems in forests throughout the region.

Elm Disease Resistance Research Gets a Boost
Year: 2016
Great news for disease-tolerant American elm! A grant from The Manton Foundation has provided the Forest Service’s Northern Research Station with an opportunity to accelerate American elm research in collaboration with Nature Conservancy.