Our geologic environment has shaped who we are here in central Pennsylvania, as it has in much of the rest of the world. Even in today’s mechanized and computerized world, the rocks and soils with which we have been blessed or cursed affect us in many ways.
Altoona grew to be a railroad city because it sat at the foot of the Appalachian Front. This escarpment (it is not technically a mountain) was the most challenging geologic obstacle for the railroad between the East Coast and the Midwest. When the Horseshoe Curve was built in 1855, it made sense to build railroad facilities in the nearby valley.
Coal mining became an important industry in Cambria County because extensive bituminous coal deposits were found on the Appalachian Plateau. The coincidence that the ingredients for steel making were nearby made Johnstown and Pittsburgh natural places to manufacture steel.
The fertile limestone soils of Morrison Cove and Sinking Valley have always been a logical and profitable place to grow food and raise livestock.
Farms are much fewer and further between in the Logan Valley (just west of Interstate 99) because the underlying rock is shale. Shale is associated with heavy, sticky clay soils and much of it in these parts is shallow as well. You don’t have to be a soil scientist to understand that such mediocre soil makes farming less profitable.
Yet one can find islands of good farmland beyond the Cove and Sinking Valley because of unique local soil situations. The most common of these are rich alluvial (or river bed) soils made from deposits laid down by rivers.
Though much more “man-made” or manufactured soils are being made these days by composters and other recyclers, Mother Nature makes fertile topsoil very slowly. Yet careless development and less than ideal agricultural practices can allow it to be washed away or covered over very quickly.
Last time we discussed the importance of preserving our mountain landscapes and protecting the soils, water resources and habitat found on their slopes. Similarly, it is important to preserve farmland and green space that is truly irreplaceable. In a world looking hard for ways to grow more food, fiber and fuel, it seems foolhardy to allow short term financial gain to be placed ahead of smart resource management for the long term.
Pennsylvania has made strides in preserving farmland yet many believe it has been too little too late. Blair County has seen suburban sprawl gobble up all kinds of green space, both agricultural and mountainside land. From many perspectives, it makes more sense to build in places where we have existing infrastructure and to grow inward rather than sprawl into these green spaces, encouraging "infill" development and "brownfield" redevelopment.
Land use decisions we make today have implications for decades and it is why we should consider those big picture issues. If we rip apart a quarter billion year old mountainside or pave over and build atop irreplaceable farmland, it’s impossible to put it back. These environmental assets have real value and our long-term environmental and economic vitality would be well served by keeping that in mind.