Soils

The Manor Series of soils is the predominant soil type in the Wissahickon Valley. These extremely stony loams, with slopes from 8-to-50 percent, generally occur from the creek up along the steep sides of the gorge.

Given the steepness of the slopes and the amount of stones on the surface, these soils are highly susceptible to erosion. This susceptibility logically suggests that any fairly intense or regular use of this ground requires a management program designed to minimize the amount of erosion.

In the upland portions of the valley, other soil types include Chester Silt Loam and Urban Land-Chester Complex. However, these soils are either on the outer edge of the Park or do not predominate as does the Manor Series.

The following are the “lowland” soils that occur along the Wissahickon:

• Rowland Silt Loam occurs on flood plains along the tributaries in areas of shale and sandstone. This soil occurs mostly in the northern fifth of the valley.
• Alluvial Land soils occur mostly in the Kitchen’s Lane area and along the lower portions of some tributaries into the main creek. It consists of frequently flooded, somewhat poorly drained soils that formed in the clay, silt, sand, gravel or similar material deposited by running water.
• Hatboro Silt Loam occurs primarily along the small tributaries and intermittent streams feeding into the Wissahickon. This soil is on smooth or slightly concave flood plains. Some of these soils support stands of moisture-tolerant trees, but other areas are too wet or stony to support any significant vegetation.