CHAPTER 4 - Western Pennsylvania Conservancy

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Connoquenessing Creek Watershed Conservation Plan Chapter 4. Biological Resources what species of tree the firewood was derived from, the ban includes all hardwoods. In addition, PDA has quarantined Allegheny, Butler, Beaver, and Lawrence counties. The quarantine restricts or prohibits the transport and sale of ash wood products and plants that may harbor the pest (DCNR, 2007a). It is not the adult emerald ash borer beetles that cause the devastating effects of girdling and killing trees, but rather their larvae that feed under the bark. As the larvae eat paths under the bark, called “galleries,” they disconnect the cells that carry nutrients and water to the limbs and leaves of the tree. Over time, usually within three years of the infestation, the tree dies as a result of stress and inability to circulate life-sustaining nutrients and water throughout the plant. EAB presence is most easily identified by the D-shaped exit holes bored into the wood of a tree. Adult beetles are approximately a half inch long and slender with dark green metallic coloration. If you suspect the presence of EAB in your area, notify your regional DNCR Bureau of Forestry, PDA, Penn State Cooperative Extension, or the EAB hotline: 1-866-253-7189. Gypsy Moth The gypsy moth was introduced to the U.S. from Europe in the 1980s. It feeds while in the larval, or caterpillar, stage. Eggs are deposited in July, and overwinter on bark and stones. Gypsy moth caterpillars hatch and begin feeding from mid- to late-April in southern Pennsylvania, and in early-to mid-May in the northern part of the state. Oaks, sugar maple, beech, and aspen trees are preferred food sources for this caterpillar’s voracious appetite. Large gypsy moth populations may strip entire trees of their foliage, leaving them weakened and susceptible to disease, drought, and attack by other pests. A tree begins to suffer when 30 percent or more of its leaf surface is lost (Purdue Research Foundation, 2004). According to the 2006 Pennsylvania Annual Pest Conditions Report compiled by DCNR, Bureau of Forestry, Division of Forest Pest Management (2006), “Gypsy moth defoliated more acres of forest than any other pest or pathogen in 2006, and is considered to be at outbreak levels.” The state of Pennsylvania initiated a suppression program in 2006, which included the cooperation of five counties, four forest districts, one state park, the PGC, and two stewardship landowners. Gypsy moth populations are expected to continue to increase and the suppression program will expand in the year 2007 to include at least 14 counties on 45,474 acres of land, though those estimates are expected to change. Gypsy moth populations are typically highest following wet, more temperate winters, while cold, dry winters cause the death of egg masses. Private landowners with forested land containing 250 or more egg masses per acre may be eligible for insecticide applications administered through the DCNR Bureau of Forestry. However, the biggest factor controlling populations is a natural fungus, which grows on most hardwoods, and adversely affects the gypsy moth (Purdue Research Foundation, 2004). Gypsy moths pose a particular threat to areas predominately composed of oak species, such as the Buhls Channel BDA, because oak is one of their preferred foods. Hemlock Woolly Adelgid This tiny, fluid-feeding insect was introduced from Japan in the early 20 th century, and was first discovered in Pennsylvania in 1969. Forty-four counties in Pennsylvania have been infected, including Allegheny County within the Connoquenessing Creek watershed. Infestation is currently heaviest in southcentral and eastern Pennsylvania, and low in the western portion, which includes the project area. Cold weather may contribute to high mortality, and will likely prevent expansion of this pest, unless global warming eventually defeats very cold weather in the area. The hemlock woolly adelgid most commonly affects hemlocks, but can also affect spruce trees (DCNR). The species prefers mild conditions, and is most active from October to June. Eggs hatch in February or March. Damage is inflicted when an immature nymph or adult sucks sap from twigs, which causes 4-28
Connoquenessing Creek Watershed Conservation Plan Chapter 4. Biological Resources hosts to lose needles, and possibly die. Biological control agents include a beetle, which was released by DCNR in 2004 on affected hemlock trees in central and southern Pennsylvania. DCNR is also in the process of establishing sites for chemical applications against the hemlock woolly adelgid (Spichiger, 2004). Zebra Mussel Zebra mussels were brought to the U.S. in the 1980s in the ballasts of European ships. Since that time, they have colonized many lakes and streams in the Great Lakes region and also the entire stretch of the Mississippi River. These thumbnail-size mussels impose damage by removing all of the microscopic food, including plankton and zooplankton, depriving other organisms, and altering the food chain (Pennsylvania Sea Grant, 2003). The Pennsylvania Zebra Mussel Monitoring Network was established in 1990–1991 to monitor the spread of zebra mussels in the state. Volunteer personnel from a variety of agencies report sightings of the species to DEP. Due to its ecological requirements; the species is restricted to slow-flowing rivers, impoundments, reservoirs, and lakes. For instance, it has been identified in the Monongahela, Ohio, and Allegheny rivers, and in French Creek above an impoundment (Shaw, personal communication, 2006). The zebra mussel is most commonly transported in ship ballasts and on recreational boats that utilize multiple waterways. Boaters should always clean their vessels thoroughly before transporting to another waterbody to prevent the spread of mussels, invasive aquatic plants, and other nuisances. According to the Connoquenessing Creek Watershed Mussel Survey (Lang, 2002) report, no zebra mussels were detected within the watershed, although the species has been detected in the Ohio River drainage. Previous Studies Connoquenessing Creek Watershed Mussel Survey, 2002 A survey was conducted along Connoquenessing Creek, Thorn Creek, Little Connoquenessing Creek, Glade Run, Brush Creek, Bonnie Brook, Breakneck Creek, and Camp Run to gather baseline data on mussel populations within the watershed. Fourteen species of freshwater mussels and clams were found through the study. Species were more diverse and individuals more abundant in the downstream third of Connoquenessing Creek, downstream of Zelienople. Several of the species’ populations were or were believed to be reproducing (fluted shell, plain pocketbook, fat mucket, creeper, giant floater, spike, and the Asiatic and pea clams), while others were present, but not reproducing (mucket, black sandshell, and rainbow, which is a Pennsylvania endangered species), and dead shells of some species (threeridge, kidneyshell, and round pigtoe) were found, though no live specimens were recorded. Bruce Kemp, a member of CWA and the watershed conservation plan steering committee, searches Connoquenessing Creek for mussels Humans have contributed to the historic decline of mussels throughout the watershed. Activities, such as industrial pollution, rechannelization from road and railroad corridors, erosion and sedimentation, pollution from abandoned mines, sewage, nutrient runoff, urban sprawl, timber harvest, and dams have adversely affected freshwater mussels in the Connoquenessing Creek. The presence, diversity, and abundance of freshwater mussels in a system act as an indicator of the water quality and health of the ecosystem. Mussels are intolerant of pollution, certain water temperatures, slow flow, and sedimentation, making them habitat-specific. Therefore, streams impacted by AMD, erosion and sedimentation, industrial pollution, damming, and 4-29
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CHAPTER 4 - Western Pennsylvania Conservancy

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