Catawissa Creek Outcrops

This locally significant site includes the forested slopes along the Catawissa Creek from where it enters the county at the Schuylkill County border to the mountain gap at Mainville. Along the banks of the creek, which are exceptionally scenic, the hemlock and hardwood forests are underlain with thick stands of rhododendron. Stony outcrops flank the water at the many sharp bends in the creek. The clear waters, at first appearing sparklingly clean, at closer inspection reveal an aquatic ecosystem nearly devoid of life. As a result, many other common animals further up the food chain are absent as well. Birds and mammals that feed on the fish, aquatic insects and other aquatic invertebrates are also lacking from this environment. Acid mine drainage (AMD) from coal mines long since abandoned, has greatly impacted this otherwise beautiful stretch of creek. Despite this unfortunate and difficult-to-remedy aquatic impairment, the forested slopes along the creek act as a buffer to the waterway, filtering runoff, providing shade to the creek and acting as an essential corridor of habitat to terrestrial animal life.

Several interesting plant species were noted along the banks of the creek. A large population of the relatively uncommon evergreen shrub American yew (Taxus canadensis) was observed hanging onto rock outcrops shaded by overarching hemlocks. This species was recently removed from the plant species of concern list based on updated statewide population estimates. Yew has been in decline over much of its range in the state due to habitat loss and over-browsing by deer. Recent documentation of several excellent quality populations of yew in Columbia County may suggest this species is truly on the rebound. The golden club (Orontium aquaticum) is another plant species that was recently removed from the species of concern list that was observed along the Catawissa Creek. This emergent aquatic plant species is spectacular when in bloom with its foot-long yellow club-like flower. A fair-quality population of this plant was found growing out of cracks in the creek bank bedrock. Several massive rock outcrops occur at bends in the creek. These outcrops provide unique habitat conditions depending on the degree of moisture, solar exposure and bedrock substrate of which the outcrops are composed. Southerly-facing outcrops tend to be dry, with a very different plant community then typically cooler, moister northerly-facing cliffs. Most of the smaller outcrops along the creek have a similar plant community with early spring wildflowers such as columbine (Aquilegia canadensis), alum-root (Heuchera americana), early saxifrage (Saxifraga virginiensis), miterwort (Mitella diphylla), moss pink (Phlox subulata), and a good variety of ferns including marginal wood fern (Dryopteris marginalis), spinulose wood fern (D. carthusiana), evergreen wood fern (D. intermedia), rock polypody (Polypody virginianum), Christmas fern (Polystichum acrostichoides), maidenhair spleenwort (Asplenium trichomanes), fragile fern (Cystopteris tenuis), New York fern (Thelypteris noveboracensis) and silvery glade fern (Deparia acrostichoides). Shrubs on these outcrops typically include wild hydrangea (Hydrangea arborescens), purple-flowering raspberry (Rubus odoratus), wild gooseberry (Ribes rotundifolium), pinxter-flower (Rhododendron periclymenoides), rosebay (Rhododendron maximum), elderberry (Sambucus canadensis) and two native bush honeysuckles (Diervilla lonicera & Lonicera canadensis). The tree canopy overarching these smaller outcrops consists primarily of Hemlock and mixed hardwoods including black birch (Betula lenta), river birch (B. nigra), basswood (Tilia americana), ash (Fraxinus sp.), red oak (Quercus rubra), shagbark hickory (Carya ovata), American elm (Ulmus americana), black cherry (Prunus serotina), choke cherry (P. virginiana), hackberry (Celtis occidentalis) and hop- hornbeam (Ostrya virginiana).

A very large and steep, dry outcrop along the creek has an interesting plant composition. Walking fern (Asplenium rhizophyllum), which is typically found on limestone, red cedar (Juniperus virginiana) and dwarf hackberry (Celtis tenuifolia) are typically found on dry sites, and American yew, which is usually found beneath the cool shade of hemlock are all growing on the same outcrop. This large, dry, loose-shale outcrop near the confluence with Mine Run was not adequately surveyed at the time of the creek survey and merits future investigations. Another very steep and high outcrop occurs further downstream at the confluence with Scotch Run. This cliff has a northerly exposure, and is very wet. The cool, shaded conditions at his location provide habitat for a different plant community. Herbaceous species found at the site include swamp saxifrage (Saxifraga pensylvanica), early saxifrage (Saxifraga virginiensis), Virginia waterleaf (Hydrophyllum virginianum), golden saxifrage (Chrysosplenium americanum), Pennsylvania bittercress (Cardamine pensylvanica), zigzag goldenrod (Solidago flexicaulis) and a variety of liverworts and moss species, which cover much of the dripping wet rock surface.

Threats and Disturbances The degraded condition of the watershed due to acid mine drainage is the main disturbance to this otherwise quality habitat. New houses built on the banks of the creek fragment the continuity of the habitat, interrupting its effect as a wildlife corridor, and potentially introduce invasive species of plants into the habitat.

Conservation Recommendations The Catawissa Creek Restoration Association (CCRA) has been very active in implementing measures designed to diminish the effects of acid mine drainage on this aquatic system. A method employed by the CCRA, along with a contingent of volunteer organizations and individuals, has been to buffer the acidity of the water with the addition of many hundreds of tons of limestone sand to the creek bed. Forested buffers should remain intact for the length of the creek with logging operations refraining from cutting within 50 to 100 feet of the creek bank. Stream bank forests help buffer the watershed from the effects of non-point sources of pollution including runoff from agricultural, residential and roadway settings. In addition, the stream bank floodplain and corridor is usually an area of significantly higher biodiversity than the adjoining uplands. Much of the area’s important biodiversity can be preserved by maintaining an intact, forested floodplain along the creek. The effectiveness of the forested creek as a habitat corridor would be diminished by fragmentation of the forest continuity by the construction of houses and additional roadways along the creek. Local planning should discourage construction of new residences and roadways along the creek, adjacent slopes and floodplain.