Philadelphia Field Station

About PFS

Philadelphia Field Station Team

[photo] Philadelphia Field Station staffThe Northern Research Station's Philadelphia Field Station (PFS) works to facilitate and develop research around urban forestry, but knows that in the urban environment, trees and forests do not exist in isolation. Conserving the urban forest involves understanding the relationship between water, air, land, and people.  The PFS team helps facilitate dialogues between practitioners and researchers from different disciplines and provides scientifically relevant research ro help inform decisions made in the “real” world.


Sarah C. Low

Sarah C. Low, USDA Forest Service

Field Station Coordinator and Biological Scientist


Sarah focuses on bridging the gaps between policy, planning, and science, specifically as it relates to the interaction of people and nature.  At the PFS, she leads a team of researchers and practitioners who focus on the role of trees, forests, and natural resources in making cities more livable.  The group specifically focuses on the ecosystem value of trees and forests, factors that influence tree mortality, socio-ecological impacts of green infrastructure, and stewardship.  The PFS works to develop and deliver science that helps decision making on the local and regional levels.  Sarah holds a Bachelor of Science in Fish and Wildlife Conservation and a Master of Science in Watershed Science and Management from the University of Massachusetts, Amherst.  She has worked in ecological restoration, community forestry, trail design, stewardship, and park management for over 10 years.


Lara A. Roman

Lara A. Roman, USDA Forest Service

Research Ecologist


Providing the ecosystem services associated with urban tree planting depends on tree survival.  With major new planting campaigns, how many of those trees will survive for decades, reaching a mature size at which their environmental and socioeconomic benefits are greatest?  How many trees are enough? How many must be planted to make a lasting impact, and meet a city’s canopy cover goals?  What are the implications of future tree death for managing the urban forest, in terms of cycles of tree removal and replacement?  Answering these most basic questions in urban forest planning requires information about tree mortality and growth rates.  Lara collects long-term urban tree monitoring data through research-practice partnerships to address the following topics:

  • Citizen science for urban forestry. Evaluating the error rates of field crews with varying levels of previous experience, to assess feasibility of large-scale volunteer urban tree monitoring, in a 5-city pilot study
  • Street tree survival in New York City. Collaborating with New York City Department of Parks & Recreation to evaluate socioeconomic and biophysical risk factors related to young tree survival.
  • Landscape and canopy change on a college campus. Collaboration with the University of Pennsylvania Green Campus Partnership to search past tree inventory records, campus photo archives, and aerial photography to describe the decades-long evolution of the campus tree cover, with a Penn sustainability intern.
  • Monitoring trees planted by the University City Green program. Tracking growth and survival of trees planted by a neighborhood organization in West Philadelphia

Michelle C. Kondo

Michelle C. Kondo, USDA Forest Service

Research Scientist


Cities across the United States are undertaking sustainability initiatives that aim to restore ecosystem functions, reduce energy consumption and heat-island effects, and improve air and water quality and public health.  One major strategy of these initiatives is the introduction of vegetation and greened spaces to once-paved, impervious or abandoned lands.  Michelle is investigating the potential role of urban greening initiatives, such as green stormwater infrastructure or vacant-lot greening, in reducing environmental hazards and improving community and ecosystem health.
Her research program addresses two themes:

  • Combined sewer overflows (CSOs). A common occurrence in cities such as Philadelphia and Camden, the combined sewer systems and storm water systems are subject to overflow during heavy rains. This causes riparian and streambed erosion, reduced water quality from introduced sediments and pollutants, increased stream temperatures, and degraded habitats, as well as public health effects from exposure to untreated sewage that ends up in streets, parks, streams, and basements.  The PFS program is intended to evaluate the potential utility of green stormwater infrastructure (GSI) in reducing storm flows in urban areas.
  • Impacts of urban greening initiatives. Programs such as GSI and vacant lot greening can have positive effects on public health and safety. Michelle is currently studying the effect of GSI and vacant-lot greening on cardiovascular health, crime, and traffic safety in Philadelphia, PA; Youngstown, OH; and Newark, NJ.

Jason Henning

Jason Henning, The Davey Institute

Research Urban Forester


Jason applies his skills in practical problem solving and communicating quantitative and computational methods to topics in natural resources.  Jason is currently focusing on i-Tree Eco samples and summaries for cities in the Lower Delaware River Watershed, StewMap for the City of Philadelphia, and i-Tree support and extension for national and international users. He holds a BS in natural resource mjanagement from Rutgers University, an MS in forestry from the University of Minnesota, Twin Cities, and an MS in statistics and a PhD in forestry from Virginia Tech.