Download or read book Impact of hemlock woolly adelgid on eastern hemlock stands in the Black Forest Cornwall New York written by Aaron Kimple and published by . This book was released on 2003 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Eastern Hemlock Forests written by Jeffrey S. Ward and published by . This book was released on 2004 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technology Transfer Hemlock Woolly Adelgid written by S. M. Salom and published by . This book was released on 1996 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Standardized Sampling for Detection and Monitoring of Hemlock Woolly Adelgid in Eastern Hemlock Forests written by Scott Costa and published by . This book was released on 2006 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Impacts of Hemlock Woolly Adelgid on Tsuga Canadensis Forest Communities in Great Smoky Mountains National Park USA written by Kurt J. Krapfl and published by . This book was released on 2010 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tsuga canadensis (L.) Carr. (eastern hemlock), a long lived and shade tolerant coniferous tree species native to eastern North America, is currently threatened by the hemlock woolly adelgid ( Adelges tsugae Annand, HWA). This exotic, invasive insect poses a serious threat to T. canadensis stands throughout their native range. The loss of this unique tree species is often coupled with numerous ecological consequences. HWA-induced mortality has exceeded 95% in some forest types, and will likely continue to decimate T. canadensis populations in the coming years. Shortly after HWA was found in Great Smoky Mountains National Park (GSMNP), long-term monitoring plots were established across a gradient of T. canadensis associated forest communities to monitor HWA impacts and stand decline. Our objectives were to (1) determine how T. canadensis populations have changed in conjunction with HWA infestation, and (2) document how HWA has affected vegetative community dynamics following five to six years of infestation in GSMNP.

Download or read book Hemlock Woolly Adelgid written by Mark S. McClure and published by . This book was released on 1996 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling The Effects Of The Hemlock Woolly Adelgid On Carbon Storage In Northern New England Forests written by Jeffrey John Krebs and published by . This book was released on 2014 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: The hemlock woolly adelgid (HWA, Adelges tsugae Annand) is an invasive insect that threatens to eradicate native eastern hemlock (Tsuga canadensis (L.) Carr.) across the eastern United States. In southern New England and southern Appalachian forests, HWA-induced hemlock mortality has impacted carbon (C) flux by altering stand age, litter composition, species composition, and coarse woody debris levels. However, no one has examined how total C storage and sequestration may be impacted by these changes. Further, while projections are that HWA will ultimately infest hemlock across its entire geographic range, the majority of studies have been limited to southern New England and Appalachian forests where HWA infestation has been ongoing. To address these gaps, we examined how HWA might alter C dynamics in northern New England forests using the Forest Vegetation Simulator (FVS) and Forest Inventory Analysis (FIA) data to model C storage and successional pathways under three different scenarios: preemptive harvesting of hemlock, HWA-induced hemlock mortality, and a control mimicking natural stand development absent of disturbance. Our 150 year simulation showed that, while all treatments differed significantly in C storage in the short term, there was no significant difference in total C stocks between HWA infestation and presalvage treatments by the 75th year. Compared to the control, both simulated treatments resulted in a significant decrease in total C storage, with greater impacts on stands with higher hemlock densities. However, net C losses over the 150 year simulation were significantly higher for the presalvage scenario, indicating that allowing HWA infestation to progress naturally through a stand may result in the least impact to long-term C sequestration for the region's forests.

Download or read book Eastern Hemlock Forests written by Jeffrey S. Ward and published by . This book was released on 2004 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Hemlock Woolly Adelgid on Ectomycorrhizal Fungi Associated with Tsuga Canadensis Eastern Hemlock in Central New York written by Matthew T. Amoia and published by . This book was released on 2017 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Economic Impact of the Hemlock Woolly Adelgid on Residential Property Values written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The hemlock woolly adelgid (HWA) is an exotic insect pest that has been causing mortality to eastern and Carolina hemlocks. The HWA is currently established in 15 eastern states and is spreading to other states where these hemlock species are found. Hemlocks are an important natural and cultural resource on many public lands throughout their range, and are widely used as ornamental trees in residential landscapes. To date, the economic impact of the historic and potential future spread of the HWA on private residential property values, has not been quantified. As the eastern hemlock is a commonly planted species in residential landscapes, valued both for its aesthetic beauty and screening purposes, it is hypothesized that hemlock health on an individual's private property will affect that home's value. Furthermore, it is theorized that hemlocks in the area surrounding an individual house are considered neighborhood amenities and will also contribute to residential property values. This research examines the economic impact of HWA on residential landscapes. A limited number of studies have been conducted to estimate the non-market economic impacts associated with forest insect pests. Most of these studies used contingent valuation methods, asking people to state their maximum willingness to pay for specific forest protection programs. Hedonic property value models can also be used to assess the economic impact of a forest pest by estimating how the value of trees is capitalized into private property values. As far as the author is aware, there has only been one published study to use the hedonic pricing method to estimate economic impacts from forest insect pests. In this study, the linkage between residential property values and HWA infestation is investigated by employing a hedonic model. Northwestern New Jersey was chosen for the study site as the HWA has already had a significant impact in this area. In addition to structural housing characteristics, environmenta.

Download or read book The Effect of Hemlock Woolly Adelgid Infestation on Water Relations of Carolina and Eastern Hemlock written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In North America, hemlock woolly adelgid (HWA; Adelges tsugae Annand) is an exotic insect pest from Asia that is causing severe decimation of native eastern hemlock (Tsuga canadensis (L.) Carr.) and Carolina hemlock (Tsuga caroliniana Engelm.). Extensive research has been committed to the ecological impacts and potential control measures of HWA, but the exact physiological mechanisms that cause tree decline and mortality are not known. Eastern and Carolina hemlock may be reacting to infestation in a manner similar to the response of Fraser fir (Abies fraseri (Pursh.) Poir.) to infestation by balsam woolly adelgid (BWA; Adelges picea Ratz.). It is known that Fraser fir produces abnormal xylem in response to BWA feeding. This abnormal xylem obstructs water movement within the trees, causing Fraser fir to die of water-stress. In this study, water relations within 15 eastern and Carolina hemlock were evaluated to determine if infestation by HWA was causing water-stress. Water potential, carbon-13 isotope ratio, stem conductivity, and stomatal conductance measurements were conducted on samples derived from those trees. In addition, branch samples were analyzed for possible wood anatomy alterations as a result of infestation. Pre-dawn branch water potential (Î ̈) measurements were more negative in infested hemlock than in non-infested trees. Carbon isotope ratios (normalized Î ́13C vs. VPDB) of the branches were more positive for infested trees, while stomatal conductance (gs) was lower in infested trees. These results indicate that infested eastern and Carolina hemlock are experiencing drought-like symptoms. Wood anatomy of the branches provided evidence that infested hemlocks are experiencing abnormal wood production in the xylem.

Download or read book Biological Control of Hemlock Woolly Adelgid written by and published by . This book was released on 2004 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hemlock written by Anthony D'Amato and published by Yale University Press. This book was released on 2014-04-29 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Eastern Hemlock, massive and majestic, has played a unique role in structuring northeastern forest environments, from Nova Scotia to Wisconsin and through the Appalachian Mountains to North Carolina, Tennessee, and Alabama. A “foundation species” influencing all the species in the ecosystem surrounding it, this iconic North American tree has long inspired poets and artists as well as naturalists and scientists. Five thousand years ago, the hemlock collapsed as a result of abrupt global climate change. Now this iconic tree faces extinction once again because of an invasive insect, the hemlock woolly adelgid. Drawing from a century of studies at Harvard University’s Harvard Forest, one of the most well-regarded long-term ecological research programs in North America, the authors explore what hemlock’s modern decline can tell us about the challenges facing nature and society in an era of habitat changes and fragmentation, as well as global change.

Download or read book Proceedings written by Katherine A. McManus and published by . This book was released on 2000 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Volatile Profiles and Resistance to Herbivory in Eastern Hemlock written by Elizabeth Alexa McKenzie and published by . This book was released on 2014 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Eastern hemlock hosts the hemlock woolly adelgid, an introduced sap-feeding insect that causes rapid deterioration of the host. Like most conifers, eastern hemlock produces a variety of constitutive and induced defenses, primarily terpenoids. To explore the relationship of terpenoid defenses with adelgid infestations, we artificially infested hemlocks at a forest site and a plantation site, and compared their terpenoid concentrations to those in control trees. Infested trees showed lower terpenoid concentrations than control trees, suggesting that eastern hemlock not only fails to induce production of terpenoids in response to adelgid infestation, but becomes less able to produce carbon-based defenses due to loss of carbon resources to the adelgid. Greater light intensity may account for consistently higher terpenoid concentrations at the plantation site, supporting the explanation that carbon limitation restricts terpenoid production. Recent studies have identified a small number of individual eastern hemlock trees that demonstrate relative resistance to the hemlock woolly adelgid. We compared concentrations of terpenoids in susceptible and relatively resistant trees, both in the forest and in propagated cuttings in a common-garden setting. Terpenoid concentrations were higher in twig tissue of resistant versus susceptible trees, across six sampling dates and at both sites. Because the common-garden cuttings were free of herbivores, the higher terpenoid concentrations are interpreted as a constitutive defense. Increased levels of monoterpenes and sesquiterpenes imply an overall increase in the input of carbon precursors to both terpenoid synthesis pathways. This result suggests either an altered growth-defense balance favoring allocation of carbon resources towards production of defenses, or overall greater carbon availability in growing twig tissue of adelgid-resistant eastern hemlock individuals. We contribute detailed terpenoid data to the study of the eastern hemlock - hemlock woolly adelgid system. Our solvent extraction method permits us to examine needle and twig tissues separately, capture minor components at low concentrations, and focus on stored rather than volatilized terpenoids. By relating terpenoid concentrations to insect densities, we explore the relationships of tentatively defensive chemistry to insect population dynamics. The question remains which terpenoids, if any, directly affect hemlock woolly adelgid and what role phenols may play in the system.

Download or read book Changes in Ecohydrological Function Due to the Loss and Replacement of Eastern Hemlock in a New England Forest written by Michael J. Daley and published by . This book was released on 2007 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: The disturbance currently occurring across the northeastern United States from the invasive pest hemlock woolly adelgid (Adelges tsugae) provides a unique opportunity to study the impact of community composition on ecosystem function. The spread of hemlock woolly adelgid has resulted in the replacement of eastern hemlock (Tsuga canadensis), an evergreen climax species, by deciduous seral species, mainly black birch (Betula lenta). Ecosystem water cycling has a large potential to be impacted by replacement of hemlock, and was the focus of this research.

Download or read book Characterizing the Impacts of the Invasive Hemlock Woolly Adelgid on the Forest Structure of New England written by Peter Brehm Boucher and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: