Scientists & Staff
Charles Flower
News Releases
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 & Products
- 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. Biological Invasions. 15(4): 931-944.
- 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). Forest Ecology and Management. 313: 300-306.
- 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. Forest Ecology and Management. 303: 143-147.
Publications & Products
- Fotis, Alexander ; Flower, Charles E.; Atkins, Jeff W.; Pinchot, Cornelia C.; Rodewald, Amanda D.; Matthews, Stephen. 2022. The short-term and long-term effects of honeysuckle removal on canopy structure and implications for urban forest management. Forest Ecology and Management
- Mikolajewski, Danielle ; D'Amico, Vince ; Sonti, Nancy F.; Pinchot, Cornelia C.; Flower, Charles E.; Roman, Lara A.; Trammell, Tara L.E. 2022. Restoring the iconic Ulmus americana to urban landscapes: Early tree growth responds to aboveground conditions. Urban Forestry & Urban Greening
- Reed, Samuel P.; Royo, Alejandro; Fotis, Alexander T.; Knight, Kathleen S.; Flower, Charles; Curtis, Peter S. 2022. The long‐term impacts of deer herbivory in determining temperate forest stand and canopy structural complexity. Journal of Applied Ecology
- 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. INFORMS Journal on Computing
- 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. In: Publication: Gen. Tech. Rep. SRS-252. Asheville, NC: U.S. Department of Agriculture Forest Service. Southern Research Station
- 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. In: Publication: Gen. Tech. Rep. SRS-252. Asheville, NC: U.S. Department of Agriculture Forest Service. Southern Research Station
- 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. Oecologia
- 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. The Wildlife Professional. 3: 44-49.
- 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. Forests
- 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. Forests
- 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. Forests
- 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). Annals of Forest Science
- 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. In: Sniezko, Richard A.; Man, Gary; Hipkins, Valerie; Woeste, Keith; Gwaze, David; Kliejunas, John T.; McTeague, Brianna A., tech. cords. 2017. Gene conservation of tree species—banking on the future. Proceedings of a workshop. Gen. Tech. Rep. PNW-GTR-963. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station: 165-169.
- 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. In: Pinchot, Cornelia C.; Knight, Kathleen S.; Haugen, Linda M.; Flower, Charles E.; Slavicek, James M., eds. Proceedings of the American elm restoration workshop 2016; 2016 October 25-27; Lewis Center, OH. Gen. Tech. Rep. NRS-P-174. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station: 68-72.
- Flower, Charles E.; Pinchot, Cornelia C.; Slavicek, James M. 2017. Restoring ecosystem resilience to urban forests using Dutch elm disease-tolerant American elm trees. In: Pinchot, Cornelia C.; Knight, Kathleen S.; Haugen, Linda M.; Flower, Charles E.; Slavicek, James M., eds. Proceedings of the American elm restoration workshop 2016; 2016 October 25-27; Lewis Center, OH. Gen. Tech. Rep. NRS-P-174. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station: 141-142.
- 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. In: Pinchot, Cornelia C.; Knight, Kathleen S.; Haugen, Linda M.; Flower, Charles E.; Slavicek, James M., eds. Proceedings of the American elm restoration workshop 2016; 2016 October 25-27; Lewis Center, OH. Gen. Tech. Rep. NRS-P-174. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station: 24-29.
- 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. In: Sniezko, Richard A.; Man, Gary; Hipkins, Valerie; Woeste, Keith; Gwaze, David; Kliejunas, John T.; McTeague, Brianna A., tech. cords. 2017. Gene conservation of tree species—banking on the future. Proceedings of a workshop. Gen. Tech. Rep. PNW-GTR-963. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station: 53-63.
- 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. In: Sniezko, Richard A.; Man, Gary; Hipkins, Valerie; Woeste, Keith; Gwaze, David; Kliejunas, John T.; McTeague, Brianna A., tech. cords. 2017. Gene conservation of tree species—banking on the future. Proceedings of a workshop. Gen. Tech. Rep. PNW-GTR-963. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. p. 199.
- Pinchot, Cornelia C.; Knight, Kathleen S.; Haugen, Linda M.; Flower, Charles E.; Slavicek, James M. 2017. Proceedings of the American elm restoration workshop 2016. Gen. Tech. Rep. NRS-P-174. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. 148 p.
- 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. Urban Forestry & Urban Greening
- 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. Gen. Tech. Rep. NRS-139. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. 18 p
- 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. In: Parra, Gregory; Lance, David; Mastro, Victor; Reardon, Richard; Benedict, Chuck, comps. 2011 emerald ash borer national research and technology development meeting; 2011 October 12-13; Wooster, OH. FHTET-2011-06. Morgantown, WV; U.S. Department of Agriculture, Forest Service, State and Private Forestry, Forest Health Protection, Forest Health Technology Enterprise Team: 115-116.
National 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 invasive pest and to plan management and conservation strategies.
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 landscape. Dutch elm disease inoculation trials initiated in Ohio in June 2016 yielded American elm cultivars that exhibit low levels of Dutch elm disease-induced decline one year later.
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.
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 currently being undertaken.
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.