AN URBAN “INVASION”

SOCIAL PERCEPTIONS OF THE EMERALD ASH BORER IN ROCHESTER

RUIHAI XU

Since its quiet arrival in the early 1990s, a little, metallic-green beetle has carved a path of destruction around the United States. Known as the emerald ash borer (EAB), this beetle, a species native to East Asia, was first detected in southeast Michigan in 2002 through infested ash wood used in shipping pallets or crates.¹ In 2010, the EAB made its way into Rochester, New York. It was first detected in several public parks and led to many localized battles to save the urban ash, a tree essential for shade and community aesthetics, much like the rest of the country. This history of the EAB’s “invasion,” a phenomenon driven by global trade and human mobility, demonstrates not only ecological devastation but also the interplay of societal values—economic utility, environmental preservation, and urban order—that frame the EAB as an “invasive” threat.

THE EAB IN THE UNITED STATES

The EAB is a native to an extensive geographic area of East Asia, including Korea, Japan, northeast China, and the Russian Far East.² The EAB has a lifespan of one to two years depending on temperatures and health of the host, plus when, and if, they lay eggs.³ It begins with adults emerging in late spring to early summer. They become more active above 25°C on sunny days, feeding and mating on the foliage of ash trees. This results in notching and damage on the leaves. Adults live for several weeks, with females averaging 40 to 74 eggs laid (and upwards of 307 eggs).⁴ Eggs are laid singly or in small clusters in bark crevices on the trunk or limbs or on exposed roots and require 7 to 18 days to hatch, depending on temperature. Larval neonates penetrate the bark to get to the cambial zone where they consume phloem and outer sapwood, creating serpentine galleries packed with frass (Figure One).⁵

FIGURE ONE
Serpentine paths carved by the emerald ash borer
(Edward Czerwinski, 2025)

The first recorded incidence of the insect in the United States was in 2002 near Detroit, Michigan. Transported from Asia, where the EAB is a relatively benign pest to the ash tree population due to natural resistance, North America provided a infection paradise for the EAB. When the insect’s larvae bore into emerald ash tree’s phloem (and thus halts nutrient transport), they produced no resistance, resulting in effectively dead trees within a few years. The relatively fast reproduction of EAB demonstrate why EAB is so lethal to North American Ash trees, which lack co-evolved defenses.

It did not take long for the EAB to expand from its origin in Michigan. Although the EAB spreads on its own, human assistance for its dispersion was unavoidable. The adult beetle can fly short distances—about one half mile.⁶ Still, the interstate spreading occurred via transport of infested firewood, nursery stock, and timber. Globalized trade pathways, fueled by the desire for low-cost timber and wood packaging, introduced the EAB to North America from Asia. Once established, economic incentives for moving firewood used for camping and residential heating along roads and rail lines further accelerated the EAB’s spread across state lines. Past regulatory gaps, such as the United States Department of Agriculture’s (USDA) and states’ patchy application of quarantines, worsened the issue since it was challenging to track the transportation of ash wood. By 2003, the EAB was detected in Ohio; in 2006, it was observed in Indiana, Illinois, and Maryland. Quarantines were established to limit the transport of ash wood, but this was a challenging task to monitor; thus, the EAB continued its spread. By 2010, the EAB had spread to fifteen states including New York; by 2025, thirty-six states and the District of Columbia and portions of Canada were infested.⁷

The most immediate ecological impacts of the EAB are the permanent loss of ash trees, disrupting forest ecosystems. In southeast Michigan, 99.7% of ash trees died by 2009; as a result, seed production ceased, and soil seed banks were depleted as no viable seeds or new seedlings were found after 2008.⁸ At the national level, the EAB now attacks 7% of basal forest area, with black ash wetlands especially important for regulating local hydrology transformed with altered water tables and carbon cycling.⁹ From a biodiversity standpoint, this means that countless other organisms that used to rely on ash for habitat or food are impacted by the reduction of ash trees. For example, over 280 species of arthropods are at risk of local extinction because they rely on these host trees. Woodpeckers and other birds who forage under the bark for EAB larvae may see a temporary population boom as they have more food to eat; however, with fewer ash species, fewer emerging trees means fewer breeding opportunities and food sources in the long run.¹⁰

The EAB is among the costliest invasive insect in United States. Annual municipal forestry budgets around the nation were increased by $280.5 million after confirmation of the EAB.¹¹ Municipal budget reallocations imply a greater proportion of funds going to tree removals and treatments and a lesser proportion going to routine trimming and planting based on long-term economic implications of forestry management. Between 2009 and 2019, 25 states across the eastern United States, including New York, spent over $10.7 billion in treatment, removals, and replanting of ash trees in their municipalities. If all susceptible ash trees were removed and replaced simultaneously, costs could reach $37.9 billion.¹²

Besides the ecological and economic consequences, EAB has significant cultural influence, particularly regarding Native American peoples that use the ash tree. Black ash basketry is handed down through generations, representing a physical, tangible craft with an intangible cultural significance. Ash trees from ancestral growing and harvesting sites are cut down to have their bark stripped.¹³ The black ash log is debarked and pounded to separate growth rings into pliable strips for weaving. Baskets range from utilitarian items to intricate works of art, embodying cultural narratives and providing economic income for artisans.

ARRIVING IN ROCHESTER

A 2009 New York State Regulation on firewood aimed at preventing the transport of invasive pests by restricting the movement of firewood within and through the state. This regulation applies to all wood forms, whether cut or uncut, split or unsplit, for the use as fuel. Further, it prohibited bringing untreated firewood from beyond the state and restricted untreated firewood from New York produced to within 50 miles of origin unless heat-treated to 160°F (71°C) for 75 minutes.¹⁴ Residential use required a self-issued Certificate of Origin while purchased treated firewood required a receipt with a source noted on it; heat-treated firewood required a “New York Approved Heat-Treated Firewood/Pest Free” stamp for free movement. 

Despite these efforts, in June of 2011, officials from the Rochester Forestry Division identified the EAB in and near Upper Falls Park on St. Paul Street in downtown Rochester. At that time, there were seventeen ash trees in the neighborhood that were infected.¹⁵ The city government took proactive measures to manage the ash tree population and reduce the negative effects of the EAB in parks and cemeteries. As part of their management strategy, they started removing ash trees that were in poor condition and replacing them with trees that are not susceptible to the EAB. They also identified 4,300 trees that needed to be treated with a pesticide.¹⁶ In 2012, evidence emerged of a more widespread EAB infestation in Scottsville and other areas in Monroe County (Figure Two).¹⁷

FIGURE TWO
Ash tree map
(City of Rochester, 2025)

In 2012, the Monroe County Emerald Ash Borer Task Force (MCEABTF) was formed. Joined by forestry professionals, scientists, and local residents, it brought a science-based approach to tackling the infestation. The MCEABTF supports public education, encouraging residents to report sightings and avoid transporting infested firewood while collaborating with the city on tree surveys and awareness campaigns. The organization cooperated with Cornell University’s Cooperation Extension Monroe County and collectively published “A Homeowner’s Guide to the Emerald Ash Borer” in an attempt to educate the public about how to recognize and report infestations and encourage them to actively participate in the protection program in the city of Rochester.

These efforts exemplify the opposition society places on pristine ecosystems, or native-dominated ecosystems, where ash symbolizes stability, versus the EAB as a disruptive alien invader that must be aggressively managed via insecticides and biocontrol for the sake of restoring the native order. The EAB is construed as “bad” in so far as it is antagonistic to local ecology.¹⁸ “Uncharismatic” invertebrates, in contrast to deer, are often killed off with no ethical discussion, given their indiscriminateness due to being of lower moral worth. The EAB label shows the trend to prioritize native species, which are seen as belonging, over foreign invaders, which are seen as threats. Strong supports from the public about the mass extermination of the EAB, whether through chemical spraying or cutting down trees, proves this. The consequence is a moral hierarchy where the ash’s native status prevails over the existence claim of the beetle.

Local news sources are partially responsible for the city’s perception of the EAB as an invasive threat. From 2002 to 2017, 77% of newspaper articles published in the United States depicted the EAB as an “unstoppable enemy,” using militaristic phrases like “combat” and “inevitable demise.”¹⁹ In 2024, an article in the Democrat & Chronicle describes New York forests as “under attack” by EAB, which can “kill trees in just three to four years,” depicting the beetle as a destructive enemy.²⁰ Highlighting the persistence of “lingering” ash trees—less than 1% of mature ashes in some locations—the piece emphasizes ecological losses, including reduced urban canopy, and economic costs, including expensive tree removals in Rochester. By pitting “native” ash against the “invasive” EAB, the piece enforces a moral ordering that supports aggressive management, grounded in cultural values of urban order and ecological preservation. The article describes New York’s forests as “under attack” by invasives like EAB, which can “kill trees in as few as three to four years.” This is the terminology that characterizes EAB as a fast-paced enemy and only serves to further establish its violent reputation. Many community voices go unheard—but researchers should be looking for them, because if the EAB spreads through infested firewood, private landowners and recreationists will be transporting it.

CONCLUSION

The connection between American ash trees and the emerald ash borer (EAB) clarifies how social values mediate ecological definitions of invasiveness. Ash trees are perceived as “native”—that is, economically useful, environmentally valuable, and culturally revered—in contrast to the “invasive” EAB, whose destructive impact is at odds with human interests. The mindset that native trees are sanctified and exotic, alien beetles demonized reveals a deeper tension: a reluctance to extend moral consideration to species that disrupt our vision of a native, orderly world.

NOTES

1. Robert A. Haack, “Emerald ash borer biology and invasion history,” in Biology and Control of Emerald Ash Borer.
2. Ibid, 3.
3. Ibid, 7.
4. Ibid, 7.
5. Ibid, 8.
6. Ibid, 5.
7. Daniel A. Herms and Deborah G. McCullough, “Emerald Ash Borer Invasion of North America: History, Biology, Ecology, Impacts, and Management,” Annual Review of Entomology 59 (2014): 13–30, https://doi.org/10.1146/annurev-ento-011613-162051.
8. Klooster, Wendy S., Kamal J. K. Gandhi, Lawrence C. Long, Kayla I. Perry, Kevin B. Rice, and Daniel A. Herms. “Ecological Impacts of Emerald Ash Borer in Forests at the Epicenter of the Invasion in North America.” Forests 9, no. 5 (2018): 250. https://doi.org/10.3390/f9050250.
9. Ibid, 9.
10. Ibid, 11.
11. Hauer, Richard J. and Ward D. Peterson. “Effects of Emerald Ash Borer on Municipal Forestry Budgets.” Landscape and Urban Planning 157 (January 2017): 98–105. https://doi.org/10.1016/j.landurbplan.2016.05.023.
12. Ibid.
13. Nathan W Siegert, Nathan W.,Deborah G. McCullough, Thomas Luther, Les Benedict, Susan Crocker, Kelly Church, and John Banks. “Biological Invasion Threatens Keystone Species Indelibly Entwined with Indigenous Cultures.” Frontiers in Ecology and the Environment 21, no. 7 (2023): 310–16. https://doi.org/10.1002/fee.2654.
14. “Firewood and Invasive Pests,” Department of Environmental Conservation, accessed May 14, 2025, https://dec.ny.gov/nature/animals-fish-plants/invasive-species/terrestrial/firewood.
15. City of Rochester, “Emerald Ash Borer,” accessed April 25, 2025, https://www.cityofrochester.gov/departments/des/emerald-ash-borer.
16. “Emerald Ash Borer found in 17 downtown Rochester trees” Rochester Democrat and Chronicle, June 15, 2011
17. Ibid.
18. Jonathan L. Clark. “Uncharismatic Invasives.” Environmental Humanities 6, no. 1 (2015): 29–52. https://doi.org/10.1215/22011919-3615889.
19. Mysha K. Clarke, Lara A. Roman, and Tenley M. Conway. “Communicating with the Public about Emerald Ash Borer: Militaristic and Fatalistic Framings in the News Media.”Sustainability 12, no. 11 (2020): https://doi.org/10.3390/su12114560.
20. Steve Howe, “What are ‘lingering trees’ and why do they matter in NY?” Rochester Democrat and Chronicle, March 7, 2024.