Atop Philadelphia's City Hall looking east - a broad flat coastal plain

Philadelphia Nature: An Overview

restored meadow at Bartram's Garden, looking toward Philadelphia
restored meadow at Bartram’s Garden, looking toward downtown Philadelphia

Philadelphia nature is all around us. Underneath the concrete and asphalt is natural landforms and habitats. The City of Philadelphia sits in a river valley.  Philadelphia is a flat city except for the northwestern area. The city is flanked by two rivers, the Delaware and the smaller Schuylkill.

 

Landforms

The landforms in Philadelphia and the Delaware Valley are the Atlantic Coastal Plain and the Piedmont Upland (map of physiographic landforms of Pennsylvania) .

The Atlantic Coastal Plain

This broad, flat sandy plain is where the bulk of the city of Philadelphia rests. Most of it only rises a several feet above sea level. City Hall sits thirty feet above sea level. And some parts of Philly (namely in South Philly near the airport) are a few feet below sea level.The Atlantic Coastal Plain extends northward into Bucks County, along the Delaware River.

The Piedmont Upland

The Piedmont Upland province is a land of red, clayey, soils and gently rolling hills. The Northwest section of the City sits on this rolling hills. The neighborhoods of West Oak Lane, East Mt. Airy, West Mt. Airy, Chestnut Hill, Germantown, Manayunk and Roxborough lie in this region. Parts of the surrounding Pennsylvania counties of Montgomery, Bucks, Chester and Delaware also sit in part or wholly in these upland hills.

Habitats

Philadelphia’s dominant bio-region is the Eastern Deciduous Forest. Within this forest is the Oak-Hickory Forest, Northern Floodplain Forest (Northern Riverine) and Freshwater Tidal Marshes.

Eastern Deciduous Forest

This forest of hardwood deciduous trees covers the eastern half of the North American Continent. The area is naturally covered with forests broken by open grassy fields, marshes and rivers. The trees are softwood evergreens in the north, deciduous trees in the middle and tropical trees and evergreens in the south. Different groups of trees characterize different habitats. A good book to learn about the ecology of  this forest is A Field Guide to Eastern Forests: North America (Peterson Field Guide).

Oak Hickory Forest, Forbidden Drive, Wissahickon Valley Park
Oak Hickory Forest, Forbidden Drive, Wissahickon Valley Park

The Oak-Hickory Forest

The main trees of this forest are oaks and hickories which drop their leaves in autumn. It is a nut-producing forest and is abundant with Blue Jays, Squirrels, Chipmunks, Turkeys and other nut-eaters. In the Wissahickon Forest of Philadelphia, the dominant trees are White Oak, Red Oak, Black Oak, Chestnut Oak and Tulip Tree.

Floodplain Forest and Wetland, Silver Lake Nature Center, Bucks County
Floodplain Forest and Wetland, Silver Lake Nature Center, Bucks County

The Northern Floodplain Forest

This forest borders rivers and waterways. The trees in this forest can survive the periodic flooding from the water level due to heavy rains and runoff. It is a habitat not sharply defined from a drier upland forest and can be spotted by the species growing along side water.The trees of this forest include: Red Maples, eastern Sycamore, Shagbark Hickory, River Birch and Sweet Gum.

Creek and Wetlands at John Heinz NWR at Tinicum
Creek and Wetlands at John Heinz NWR at Tinicum

Freshwater Tidal Marsh

This community consists of soft-bodied emergent plants which grow partially in and partly out of the water. In Philadelphia, the best site to see this is Tinicum (John Heinz National Wildlife Refugee) in South Philly. Here the tides from the Delaware River (and human-made) systems cause the water levels to rise and fall.

Downloadable booklets of native trees, shrubs and flowers of Philadelphia.

PA Plant communities

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