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“Bundling Priorities” in the New Central Appalachian Office The landscapes of the central Appalachian region are unique in the state with unusual ecosystems harboring species known in few other places on earth. WPC’s new Central Appalachian Office will serve three priority conservation areas as WPC determined by the development of last year’s conservation blueprint: the Potomac Tributaries; the Juniata River and the Nittany Valley. Each region is identified by its own setting and contributions to the sum total biodiversity of the Commonwealth, including forests, streams, significant habitats and species. Each also brings legacies that are as challenging as they are awe-inspiring.
The southernmost region of central Pennsylvania is composed of mountains of the Ridge and Valley Province (named for the parallel ridges and valleys of the Appalachian Mountains, which create an alternating pattern) and intermountain tributary watersheds of the Potomac River. This rugged and rural landscape includes the signature “shale country” and is based on unique geology and soils. Forests are mostly composed of species of oaks and hickories, being largely confined to slopes and ridgelines. The hot and dry shale barrens habitat exists as occasional openings along streams at lower elevations. Characteristic species include bird’s-foot violet, redbud, hognose snake and the Potomac sculpin, a small fish. The valleys are narrow but locally productive for crops and livestock. Attention to agricultural techniques is needed to protect the aquatic life in this landscape. The major streams here all flow to the Mason-Dixon Line and cross into Maryland to add their waters to the Potomac, the second largest source for the great Chesapeake Bay. The Juniata River This river is a major tributary of the Susquehanna River and its eastward course drains portions of the Ridge and Valley Province of south central Pennsylvania. Water gaps are typical features of this region, whereby seemingly against reason, large streams like the Juniata endeavor to slice through mountain ridges rather than flow submissively along their bases. Also characteristic of this landscape are the abruptly folded mountains with hard Silurian sandstone tops and lower ridges of fractured Devonian shales. The interesting and localized shale barren habitats are found here supporting lifeforms odd to most Pennsylvanians, such as prickly-pear cactus and fence lizards. Significant forest blocks are at higher elevations and the valleys support rich farmlands. In many intermountain bottomlands exists an underworld of limestone rock layers that have been partially dissolved over time resulting in plentiful aquifers of water supply and cave habitats supporting populations of animals obligated to live all or part of their lives underground, such as hibernating bats and cave shrimp. In other corners the limestone outcrops as cliffs and rocky slopes, supporting still other rare plants and animals so adapted to seek out calcium-rich habitat. Some of the rarest habitat types are forests, not the high elevation ones, but those that once occurred in the sweet soils of the riparian zones and bottomlands now supporting cropland and pastures. The valley is found precisely at the geographic center of Pennsylvania in Centre and Huntingdon counties between two long mountain ridges: Bald Eagle Mountain and Tussey Mountain. Biodiversity significance is not as much on these mountains, as within the intermountain lowlands. Here the bedrock geology is composed of multiple limestones and the rare gravelly Gatesburg Formation. This is one of the most unique landscapes in the state and includes a mixture of pitch pine-scrub oak sand barrens habitat, dotted with vernal pools, the Spring Creek valley with its alkaline soils, limestone cliffs and rich vegetation; karst (cave permeated) valleys underlain with limestone aquifers, sinkholes and solutional caves. The outflows from groundwater reserves form some of the largest natural springs in the region and are the source for high-quality streams such as the cold and clear Spruce Creek. These unusual ecosystems harbor rare species, such as Stellmack’s cave amphipod and Franz’s cave isopod, crustaceans known from few other places on Earth. As in other sectors of the Central Appalachian Mountains, low elevation forests have been reduced to small patches in a fragmented landscape. In addition to protecting water quality and quantity, the restoration of lowland forests will be another conservation challenge. The Central Appalachian Office is slated to open in Spring 2007 and will be |
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