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the Philadelphia skyline and trees

Preserving Philadelphia’s Heritage Trees at Penn

A before and after photo: the before is of a green space with 85-year-old trees and cars parked in between them; the after is of the same green space without the cars and protective fencing in front of the trees.
Before and After

The Penn Campus Arboretum is home to over 6,500 trees and 240 species in West Philadelphia. Keeping the trees alive and thriving in an urban setting is an ongoing task for Penn’s Facilities & Real Estate Services (FRES) and Morris Arboretum’s Urban Forestry team who partner to manage and improve Penn’s green infrastructure. Towards this goal, a recent project involved improving the soil conditions around seven large London planetrees, each approximately 85 years old, which are part of an allée or line of trees along River Fields Drive.

These important Philadelphia heritage trees were being negatively impacted from unsanctioned parking on the grassy spaces between each tree resulting in the soil being extremely compacted, which was harming the trees’ structural and biological root health. Roots are the life blood of trees, absorbing and transporting vital water and minerals to the tree and anchoring/stabilizing them in the ground. Because of the impact from car-related compaction to the soil and roots, the overall longevity of these trees was being threatened. 

To ensure the biological health and longevity of these magnificent London planetrees, FRES, with the help of the Urban Forestry team, proposed that the degraded soil be decompacted and enriched with leaf compost, and a low barrier fence be installed so that no further parking could occur between the trees. As a result of this FRES-funded project, the trees are well on their way to surviving another 85 years.