Benson Swamp BDA The core of this BDA is delineated around hemlock - mixed hardwood palustrine forest with pockets of scrub-/emergent wetlands that support six species of special concern. Clinton’s woodfern (Dryopteris clintoniana) occurs in swampy woods, especially red maple (Acer rubrum) swamps. It is at the southern extent of its range here in Pennsylvania and is considered imperiled, being found in only a few counties. Globally, it is considered secure, ranging from the northeastern U.S. as far west as Illinois and as far south as Maryland. Soft- sedge (Carex disperma) is a Pennsylvania rare species that occurs in bogs and wet acidic woods (Rhoads and Block 2000). Though secure and widespread in northern North America, it is rare in Pennsylvania, known from some of the northern counties. Red current ( triste), a threatened species in Pennsylvania, grows in wet, rocky woods, swamps and cliffs (Rhoads and Block 2000), especially where the water is alkaline. It occurs in the northwestern and northeastern parts of the Commonwealth. Highbush-cranberry (), a vulnerable plant species in Pennsylvania, is found in swamps, fens, and wet woods. Its range extends from southern Canada south to Kentucky and Missouri and it has only been recorded in several counties in Pennsylvania. Some botanists have considered this species to be a variety of Viburnum opulus, an introduced invasive species in southeastern Pennsylvania that is thought to be a threat to V. trilobum. Lesser panicled sedge (Carex diandra) is distributed across northern Canada and as far south as Maryland and California. In Pennsylvania it is Threatened and has only been recorded in several northern counties. It is rare in bog hummocks and along the edges of ponds (Rhoads and Block 2000). Also found here is a sensitive species of concern that cannot be named at the request of the jurisdictional agency overseeing its protection.

Over half of the core of this BDA is contained within State Game Land #306. The headwaters section of Coffee Creek flows through this wetland complex before joining Little Brokenstraw Creek. Two small creeks, Cold Spring Brook and Pine Valley Creek, join Coffee Creek within the wetland complex. There are graminoid/forb meadows; extensive shrubby thickets of spirea (Spirea sp.), swamp rose (Rosa palustris), wild black currant (Ribes americanum), and willows (Salix spp.); and areas of cattail (Typha spp.) present at the site. Alder (Alnus spp.) thickets are along most of the stream courses.

Forested areas in the northern portion of the wetland are comprised of eastern white pine (Pinus strobus), red maple (Acer rubrum), eastern hemlock (Tsuga canadensis), black birch (Betula lenta), yellow birch (B. alleghaniensis), balsam fir (Abies balsamea ), black ash (Fraxinus nigra), quaking aspen (Populus tremuloides), American elm (Ulmus americana), ironwood (Ostrya virginiana), hornbeam (Carpinus caroliniana), deciduous holly (Ilex verticillata), spicebush (Lindera benzoin), and red osier dogwood (Cornus sericea). There are hummocks in hydric areas surrounded by slowly moving water.

Dominant herbaceous species at the site include sensitive fern (Onoclea sensibilis), bedstraw (Gallium sp.), swamp saxifrage (Saxifraga pennsylvanica), turtlehead (Chelone glabra), spike- moss (Selaginella sp)., jewelweed (Impatiens sp.), swamp dewberry (Rubus hispidus), avens (Geum sp.), speckled alder (Alnus rugosa), wild sarsaparilla (Aralia nudicaulis), several sedge species (Carex canescens, C. disperma, C. stipata, C. trisperma, C. intumescens), wild calla (Calla palustris), oxeye daisy (Leucanthemum vulgare), water horehound (Lycopus uniflorus), a moss species (Mnium sp)., interrupted fern (Osmunda claytoniana), halberd-leaved tearthumb (Polygonum arifolium), bur-reed (Sparganium sp)., sphagnum mosses (Sphagnum spp)., starflower (Trientalis borealis), and American false hellebore (Veratrum viride).

Most of the western end of the swamp is pastured or has been pastured in the past. Old fence lines still remain. Little forest exists in the west end probably due to beaver activity or logging for pasture land. An Erie-Lackawanna railroad right-of-way runs along the south side of Benson Swamp and bisects a large portion of the wetland. Pastures and fields border the swamp to the north along route 957. Oil and gas wells are present along the edge of the swamp. Much of the upland landscape surrounding the core of this BDA is in agricultural production. The slopes and wetlands are largely forested.

Threats and Stresses Viburnum leaf beetle (Pyrrhalta viburni) is an introduced pest that eats highbush cranberry and other species of Viburnum. Within Pennsylvania, this pest has spread throughout the range of highbush cranberry, and is decimating populations of the shrub. It is not known whether this population has been colonized by beetles yet, but all populations of highbush cranberry are at serious risk.

The remaining forest found within the immediate watershed of this site is important in maintaining the water quality of this wetland complex, natural nutrient cycles in its associated streams, and the health of adjacent habitats. Removal of forest cover on steep slopes is especially problematic because of the potential for increased runoff and erosion following storm events. The most immediate threat to these wetlands may be an influx of non-point source pollution from agricultural and residential areas (e.g., field and road runoff) within the immediate watershed into the site due to upland agriculture. Gas wells in the site have already degraded habitat quality in some areas as demonstrated by less vegetative diversity in those areas. Runoff from dirt and gravel roads in close proximity to the wetlands can contribute to physical degradation of the site. The railroad right-of-way has impeded water flow within the site, potentially threatening all of the wetland here, but especially the lesser panicled sedge, which is an edge-adapted species with narrow hydrologic requirements (Gage and Cooper 2006).

Conservation Recommendations Management options for the control of viburnum leaf beetle should be investigated.

Remaining forest cover in the immediate watershed surrounding Benson Swamp should be left intact to provide a buffer against non-point source pollutants such as sediments and chemicals. Establishing riparian buffers adjacent to the stream and encouraging local landowners to properly manage agricultural nutrients would aid in lessening the input of runoff into the stream. The U.S. Environmental Protection Agency’s (EPA) Agricultural Management Practices for Water Quality Protection module (available online at http://www.epa.gov/watertrain/agmodule/) outlines eight basic types of agricultural practices that are suitable for reducing or minimizing water quality impacts as part of a watershed approach to management. These practices are often called Best Management Practices, or BMPs.