Speaker: Dr. Glenn Matlack, Department of Environmental & Plant Biology, Ohio University

Title: Life and Death in a Human-Constructed Ecosystem: Long-Term Dynamics of Athens’s Urban Forest

Date/Time & Location: Friday, November 14, 2025, 11:50 AM – 12:45 PM, Porter Hall 104

The urban forest appears stable and unchanging to most city dwellers, secure beyond the range of human influence.  However, when viewed in terms of an individual tree’s lifespan, cities are dynamic and dangerous constantly changing according to the whims of the trees’ human neighbors.  Athens City offers a convenient microcosm of the long-term urban forest dynamics seen in all moist-temperate zone cities.

Using historical maps and photographs, I reconstruct 200 years of Athen’s urban forest history.  Athens was initially cleared of forest between 1800-1840 following a grid plan laid out by real estate speculators only modified around inconvenient slopes and drainage.  Many trees survived in the commercial core of the City until cleared during a period of economic expansion between 1900-1920.  Surrounding neighborhoods lost their trees between 1950-1980 as the city’s population rapidly expanded and trees were removed to accommodate cars and suburban development.  Insect pests and fungal pathogens have removed large numbers of American elms and ash.

With little opportunity to naturally regenerate, maintenance of the urban forest is dependent on replacement planting by humans.  Planting rate has varied enormously from decade-to-decade with periods of great enthusiasm in the 1930s, 1950s, and 1990s separated by a long phase of benign neglect between 1960-1990.  Most planting efforts have been at the scale of single blocks or individual trees.  At present, the trees planted in the 1990s are slowly dying, apparently due to inadequate root space and constant abuse.  Planting in the 2020s has been restricted to peripheral areas of the city, and is not adequate to maintain the ecosystem services that trees provide.  This is particularly worrying in a period of climate change because trees are probably the cheapest and easiest response!