Union City Reservoir NHA

This site is designated around the Union City Reservoir and the surrounding forest, meadow, and wetland habitat. The 32 acre reservoir was created in 1935 when Bentley Run was dammed to provide a source a drinking water for Union City. Although the reservoir was artificially created, it now supports several species of concern, including three species of concern: lance tipped darner (Aeshna constricta), black-tailed darner (Aeshna tuberculifera), and lilypad clubtail ( furcifer). The reservoir also supports white water- crowfoot (Ranunculus aquatilis var. diffusus). The Oldenettel Jerry reservoir’s earthen dam provides habitat for claybank White water crowfoot tiger beetles (Cicindela limbalis).

Meadow areas near the lower reservoir, and a right-of-way that crosses Bentley Run below the reservoir, provide habitat for Leonard’s skippers (Hesperia leonardus) and northern crescents (Phyciodes cocyta). Wetlands in this area hosting stands of turtlehead (Chelone glabra), a wetland plant, support Baltimore checkerspots (Euphydras phaeton). A seepage wetland southeast of the reservoir supports variegated horsetail (Equisetum variegatum), a fen specialist plant. The presence of this plant, as well as the wetland’s geology, topology, and appearance on aerial photos, indicates that the wetland is an alder-leaved buckthorn – inland sedge – golden ragwort shrub fen, although a community survey has not been done at this site. This natural community type is critically imperiled in Pennsylvania and has potential to support numerous other rare species (Podniesinski 2011). The low, wet forest between the reservoir and the hatchery provides habitat for the globally rare West Virginia white (Pieris virginiensis). The Appalachian blue violet (Viola appalachiensis) occurs in dry,mowed areas near the

Species or natural communities of concern that can be found in this NHA include the following:

PNHP Rank1 PA Legal Species or Natural Community Name Global State Status1 Last Seen Quality2

Lance-tipped darner (Aeshna constricta) G5 S3S4 N 2010-08-27 E Black-tipped darner (Aeshna tuberculifera) G4 S2S3 N 2010-08-27 E Lilypad clubtail (Arigomphus furcifer) G5 S2 N 2005-06-26 E Claybank tiger beetle (Cicindela limbalis) G5 S3 N 2007-08-28 E Baltimore (Euphydryas phaeton) G4 S3 N 2007-07-05 E Leonard's skipper (Hesperia leonardus) G4 S3 N 2011-08-27 E Northern crescent (Phyciodes cocyta) G5 S2 N 2011-06-13 E West Virginia white (Pieris virginiensis) G3? S2S3 N 2009-04-29 E Gray comma (Polygonia progne) G4G5 S3 N 2007-07-28 E Variegated horsetail (Equisetum variegatum) G5 S1 PE 1992-07-06 BC White water-crowfoot G5T5 S3 N (PR) 1992-07-06 AB (Ranunculus aquatilis var. diffusus) Appalachian blue violet (Viola appalachiensis) G4 S3S4 PT (TU) 2009-04-29 AC

1 = Please refer to the PNHP website (http://www.naturalheritage.state.pa.us/RankStatusDef.aspx) for an explanation of PNHP ranks and legal status. A legal status in parentheses is a status change recommended by the Pennsylvania Biological Survey. 2 = Please refer to the NatureServe website (http://www.natureserve.org/explorer/eorankguide.htm) for an explanation of quality ranks. hatchery ponds and might also be elsewhere in the area. The forest in this area supports the gray comma (Polygonia progne).

Threats and Stresses

Specific threats and stresses to the elements present at this site include the following: • Fragmentation of the forest is a serious threat to the West Virginia white, because these butterflies do not cross wide roads or other non-forested areas. The result is that populations are becoming genetically isolated, and if a population is extirpated the chances are low that remaining populations will be able to recolonize the habitat. • An even greater threat to the West Virginia white is the spread of garlic mustard (Alliaria petiolata). This invasive plant is in the same Pete Woods, PNHP family (the mustard family) as toothworts, and Bentley Run, below the reservoir and above the the chemical signatures of the plants are fish hatchery. similar enough that female butterflies will readily lay their eggs on garlic mustard. The caterpillars, however, cannot survive on garlic mustard, and these butterflies have disappeared from areas where garlic mustard is dominant. Garlic mustard was not observed at this site, but it is common in the area and is expected to arrive here eventually. • High densities of white-tailed deer pose another threat to West Virginia whites, because deer browsing greatly reduces the abundance of many of the wildflowers that are crucial nectar sources for the butterflies. Although their flight period is short, adults rely on several successive waves of spring wildflowers to produce a steady supply of nectar. A reduction in abundance or diversity of spring wildflowers can leave these butterflies without a source of food. • and damselflies rely on good water quality, although the tolerances of individual species to different types of pollution are not well-understood. Erosion, whether caused by deforestation, poor agricultural practices, or the destruction of riparian zones, leads to increased silt loads and shifting, unstable stream bottoms. Siltation and contaminants such as heavy metals and pesticides are potential threats to these species. • Pesticide use at this site would threaten the numerous species of concern. • The low wet woods along Bentley Run, and around the fen, are dominated by eastern hemlock (Tsuga canadensis). The hemlock woolly adelgid (Adelges tsugae), native to Asia, is a sap- feeding insect that attacks eastern hemlock. As of 2011, the hemlock woolly adelgid is still several counties away to the east and south, but it is expected to arrive in coming years, with devastating effects on hemlock populations. Infestations are followed by high levels of hemlock mortality, which opens up the forest canopy and drastically alters the forest habitat. • The greatest threats to fen communities are disruptions to bedrock or glacial deposits (such as drilling or mining in nearby areas) and groundwater extraction, which can contaminate or alter the flow patterns of the groundwater that feeds the seepage wetlands. • Groundwater pollution in fens can occur from improperly installed septic systems, improperly lined underground waste disposal, and in agricultural areas from infiltration of pesticides, fertilizers, or bacteria from wastes. The forested buffer between the fen and upslope agricultural fields is only 50 meters wide; the groundwater recharge area for the fen is largely in agriculture and thus potentially exposed to pollution. • Peatlands such as this fen are particularly sensitive to trampling, soil compaction, and other physical disturbance from recreational activities.

Conservation Recommendations

Portions of the Core Habitat are owned by the Borough of Union City, and the Pennsylvania Fish and Boat Commission, and the remainder is in private ownership. No conservation easements are in place.

The following steps are recommended to ensure the persistence of these species at this site: • Monitoring for and controlling garlic mustard and other invasive species is critical for is important for the persistence of West Pete Woods, PNHP Virginia whites at this site. Fragmentation of the remaining forest should be avoided. Appalachian blue violet, a threatened plant New development such as housing, roads, species, photographed at this site.

and powerlines should be concentrated in areas that have already been disturbed. White-tailed deer should be kept to a low density to avoid degradation of the forest’s diversity. • As of 2012, available treatments for hemlock woolly adelgid are not economically feasible at a scale suitable for large natural areas. At a smaller scale, injection of insecticides into tree trunks or into the soil around a tree can control adelgids for up to several years at a time, although there may be unintended effects on other species. Continued applications of horticultural oil or insecticidal soap can also control hemlock woolly adelgids. Biological controls are being researched, although they have so far had limited success at keeping adelgid populations in check (DCNR 2012). • Drilling, mining, or other disruptions to bedrock or glacial deposits should not be undertaken within half a mile of a seepage wetland without a thorough understanding of bedrock layers and groundwater flows. Groundwater flow patterns do not always mirror surface watersheds, and in some cases aquifers may be contiguous over large areas. • Natural buffer around the reservoir, wetlands, and stream should be maintained in order to minimize nutrient runoff, pollution, and sedimentation. The use of pesticides should be avoided within the Surrounding Landscape.

Location and Additional Information

Municipalities: Union Township USGS quads: Union City 1993 Erie CNHI reference: Alder Run, Bentley Run BDA Associated NHAs: Alder & Bently Run Kame Field NHA, Boleratz Fen NHA, Hell’s Half Acre NHA, Kirik Fen NHA, Union City Hatchery Fen NHA Overlapping Protected Lands: None; private land. PNHP Significance Rank: Regional

References

Department of Conservation and Natural Resources. 2012. Forest Health Fact Sheet: Hemlock Woolly Adelgid. http://www.dcnr.state.pa.us/ucmprd2/groups/public/documents/document/dcnr_007179.pdf Podniesinski 2011. Pennsylvania Natural Heritage Program. Alder-leaved Buckthorn – Inland Sedge – Golden Ragwort Shrub Fen Factsheet. Available from: http://www.naturalheritage.state.pa.us/Community.aspx?=30002 Date Accessed: August 01, 2012